1Exam #131 Page: 1 Name: _____________________________________

131

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #131 Page: 2 Name: _____________________________________

131

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -17,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -48,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11011110 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11110111 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10111111 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #131 Page: 3 Name: _____________________________________

131

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #131 Page: 4 Name: _____________________________________

131

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #131 Page: 5 Name:_____________________________________

131

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #131 Page: 6 Name: _____________________________________

131

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #131 Page: 7 Name: _____________________________________

131

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #131 Page: 8 Name:_____________________________________

131

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #132 Page: 1 Name: _____________________________________

132

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #132 Page: 2 Name: _____________________________________

132

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -61,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -28,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11011101 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10001010 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11101110 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #132 Page: 3 Name: _____________________________________

132

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #132 Page: 4 Name: _____________________________________

132

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #132 Page: 5 Name:_____________________________________

132

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #132 Page: 6 Name: _____________________________________

132

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #132 Page: 7 Name: _____________________________________

132

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #132 Page: 8 Name:_____________________________________

132

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #133 Page: 1 Name: _____________________________________

133

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #133 Page: 2 Name: _____________________________________

133

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -50,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -10,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11000001 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10010001 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11010101 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #133 Page: 3 Name: _____________________________________

133

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #133 Page: 4 Name: _____________________________________

133

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #133 Page: 5 Name:_____________________________________

133

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #133 Page: 6 Name: _____________________________________

133

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #133 Page: 7 Name: _____________________________________

133

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #133 Page: 8 Name:_____________________________________

133

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #134 Page: 1 Name: _____________________________________

134

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #134 Page: 2 Name: _____________________________________

134

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -120,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -113,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10101010 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10011100 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10101000 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #134 Page: 3 Name: _____________________________________

134

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #134 Page: 4 Name: _____________________________________

134

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #134 Page: 5 Name:_____________________________________

134

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #134 Page: 6 Name: _____________________________________

134

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #134 Page: 7 Name: _____________________________________

134

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #134 Page: 8 Name:_____________________________________

134

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #135 Page: 1 Name: _____________________________________

135

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #135 Page: 2 Name: _____________________________________

135

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -26,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -7,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11000011 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11010011 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11001011 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #135 Page: 3 Name: _____________________________________

135

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #135 Page: 4 Name: _____________________________________

135

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #135 Page: 5 Name:_____________________________________

135

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #135 Page: 6 Name: _____________________________________

135

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #135 Page: 7 Name: _____________________________________

135

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #135 Page: 8 Name:_____________________________________

135

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #136 Page: 1 Name: _____________________________________

136

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #136 Page: 2 Name: _____________________________________

136

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -71,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -115,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11000011 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11100110 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11111010 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #136 Page: 3 Name: _____________________________________

136

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #136 Page: 4 Name: _____________________________________

136

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #136 Page: 5 Name:_____________________________________

136

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #136 Page: 6 Name: _____________________________________

136

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #136 Page: 7 Name: _____________________________________

136

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #136 Page: 8 Name:_____________________________________

136

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #137 Page: 1 Name: _____________________________________

137

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #137 Page: 2 Name: _____________________________________

137

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -105,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -9,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11011100 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10011101 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10011100 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #137 Page: 3 Name: _____________________________________

137

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #137 Page: 4 Name: _____________________________________

137

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #137 Page: 5 Name:_____________________________________

137

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #137 Page: 6 Name: _____________________________________

137

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #137 Page: 7 Name: _____________________________________

137

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #137 Page: 8 Name:_____________________________________

137

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #138 Page: 1 Name: _____________________________________

138

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #138 Page: 2 Name: _____________________________________

138

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -2,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -72,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10010000 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11111000 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10110100 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #138 Page: 3 Name: _____________________________________

138

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #138 Page: 4 Name: _____________________________________

138

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #138 Page: 5 Name:_____________________________________

138

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #138 Page: 6 Name: _____________________________________

138

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #138 Page: 7 Name: _____________________________________

138

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #138 Page: 8 Name:_____________________________________

138

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #139 Page: 1 Name: _____________________________________

139

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #139 Page: 2 Name: _____________________________________

139

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -36,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -93,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10101001 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10101111 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11010111 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #139 Page: 3 Name: _____________________________________

139

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #139 Page: 4 Name: _____________________________________

139

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #139 Page: 5 Name:_____________________________________

139

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #139 Page: 6 Name: _____________________________________

139

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #139 Page: 7 Name: _____________________________________

139

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #139 Page: 8 Name:_____________________________________

139

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #140 Page: 1 Name: _____________________________________

140

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #140 Page: 2 Name: _____________________________________

140

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -80,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -74,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10101001 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11000010 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10000101 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #140 Page: 3 Name: _____________________________________

140

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #140 Page: 4 Name: _____________________________________

140

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #140 Page: 5 Name:_____________________________________

140

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #140 Page: 6 Name: _____________________________________

140

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #140 Page: 7 Name: _____________________________________

140

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #140 Page: 8 Name:_____________________________________

140

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #141 Page: 1 Name: _____________________________________

141

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #141 Page: 2 Name: _____________________________________

141

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -115,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11000010 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11111001 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10101000 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #141 Page: 3 Name: _____________________________________

141

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #141 Page: 4 Name: _____________________________________

141

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #141 Page: 5 Name:_____________________________________

141

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #141 Page: 6 Name: _____________________________________

141

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #141 Page: 7 Name: _____________________________________

141

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #141 Page: 8 Name:_____________________________________

141

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #142 Page: 1 Name: _____________________________________

142

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #142 Page: 2 Name: _____________________________________

142

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -11,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -30,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11110110 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11010100 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10111111 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #142 Page: 3 Name: _____________________________________

142

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #142 Page: 4 Name: _____________________________________

142

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #142 Page: 5 Name:_____________________________________

142

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #142 Page: 6 Name: _____________________________________

142

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #142 Page: 7 Name: _____________________________________

142

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #142 Page: 8 Name:_____________________________________

142

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #143 Page: 1 Name: _____________________________________

143

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #143 Page: 2 Name: _____________________________________

143

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -46,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -52,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10001111 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10001011 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11100010 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #143 Page: 3 Name: _____________________________________

143

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #143 Page: 4 Name: _____________________________________

143

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #143 Page: 5 Name:_____________________________________

143

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #143 Page: 6 Name: _____________________________________

143

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #143 Page: 7 Name: _____________________________________

143

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #143 Page: 8 Name:_____________________________________

143

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #144 Page: 1 Name: _____________________________________

144

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #144 Page: 2 Name: _____________________________________

144

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -12,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -106,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11100000 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10111110 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10110011 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #144 Page: 3 Name: _____________________________________

144

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #144 Page: 4 Name: _____________________________________

144

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #144 Page: 5 Name:_____________________________________

144

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #144 Page: 6 Name: _____________________________________

144

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #144 Page: 7 Name: _____________________________________

144

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #144 Page: 8 Name:_____________________________________

144

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #145 Page: 1 Name: _____________________________________

145

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #145 Page: 2 Name: _____________________________________

145

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -47,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -128,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11111001 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11110101 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11010110 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #145 Page: 3 Name: _____________________________________

145

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #145 Page: 4 Name: _____________________________________

145

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #145 Page: 5 Name:_____________________________________

145

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #145 Page: 6 Name: _____________________________________

145

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #145 Page: 7 Name: _____________________________________

145

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #145 Page: 8 Name:_____________________________________

145

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #146 Page: 1 Name: _____________________________________

146

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #146 Page: 2 Name: _____________________________________

146

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -71,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -63,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10101101 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11010000 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11101110 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #146 Page: 3 Name: _____________________________________

146

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #146 Page: 4 Name: _____________________________________

146

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #146 Page: 5 Name:_____________________________________

146

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #146 Page: 6 Name: _____________________________________

146

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #146 Page: 7 Name: _____________________________________

146

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #146 Page: 8 Name:_____________________________________

146

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #147 Page: 1 Name: _____________________________________

147

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #147 Page: 2 Name: _____________________________________

147

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -106,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -85,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11000110 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10000111 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10010000 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #147 Page: 3 Name: _____________________________________

147

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #147 Page: 4 Name: _____________________________________

147

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #147 Page: 5 Name:_____________________________________

147

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #147 Page: 6 Name: _____________________________________

147

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #147 Page: 7 Name: _____________________________________

147

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #147 Page: 8 Name:_____________________________________

147

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #148 Page: 1 Name: _____________________________________

148

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #148 Page: 2 Name: _____________________________________

148

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -22,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -65,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11000110 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10011010 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11111100 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #148 Page: 3 Name: _____________________________________

148

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #148 Page: 4 Name: _____________________________________

148

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #148 Page: 5 Name:_____________________________________

148

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #148 Page: 6 Name: _____________________________________

148

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #148 Page: 7 Name: _____________________________________

148

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #148 Page: 8 Name:_____________________________________

148

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #149 Page: 1 Name: _____________________________________

149

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #149 Page: 2 Name: _____________________________________

149

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -56,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -87,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11011111 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11010001 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11100010 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #149 Page: 3 Name: _____________________________________

149

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #149 Page: 4 Name: _____________________________________

149

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #149 Page: 5 Name:_____________________________________

149

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #149 Page: 6 Name: _____________________________________

149

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #149 Page: 7 Name: _____________________________________

149

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #149 Page: 8 Name:_____________________________________

149

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #150 Page: 1 Name: _____________________________________

150

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #150 Page: 2 Name: _____________________________________

150

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -81,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -22,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10010011 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10101100 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11111001 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #150 Page: 3 Name: _____________________________________

150

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #150 Page: 4 Name: _____________________________________

150

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #150 Page: 5 Name:_____________________________________

150

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #150 Page: 6 Name: _____________________________________

150

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #150 Page: 7 Name: _____________________________________

150

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #150 Page: 8 Name:_____________________________________

150

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #151 Page: 1 Name: _____________________________________

151

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #151 Page: 2 Name: _____________________________________

151

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -115,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -43,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10101100 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11100011 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10011100 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #151 Page: 3 Name: _____________________________________

151

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #151 Page: 4 Name: _____________________________________

151

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #151 Page: 5 Name:_____________________________________

151

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #151 Page: 6 Name: _____________________________________

151

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #151 Page: 7 Name: _____________________________________

151

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #151 Page: 8 Name:_____________________________________

151

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #152 Page: 1 Name: _____________________________________

152

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #152 Page: 2 Name: _____________________________________

152

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -32,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -24,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10101011 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11110110 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11001011 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #152 Page: 3 Name: _____________________________________

152

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #152 Page: 4 Name: _____________________________________

152

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #152 Page: 5 Name:_____________________________________

152

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #152 Page: 6 Name: _____________________________________

152

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #152 Page: 7 Name: _____________________________________

152

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #152 Page: 8 Name:_____________________________________

152

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #153 Page: 1 Name: _____________________________________

153

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #153 Page: 2 Name: _____________________________________

153

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -66,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -46,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11000101 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10101101 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11101110 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #153 Page: 3 Name: _____________________________________

153

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #153 Page: 4 Name: _____________________________________

153

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #153 Page: 5 Name:_____________________________________

153

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #153 Page: 6 Name: _____________________________________

153

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #153 Page: 7 Name: _____________________________________

153

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #153 Page: 8 Name:_____________________________________

153

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #154 Page: 1 Name: _____________________________________

154

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #154 Page: 2 Name: _____________________________________

154

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -91,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -108,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11111000 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10001000 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10000101 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #154 Page: 3 Name: _____________________________________

154

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #154 Page: 4 Name: _____________________________________

154

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #154 Page: 5 Name:_____________________________________

154

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #154 Page: 6 Name: _____________________________________

154

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #154 Page: 7 Name: _____________________________________

154

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #154 Page: 8 Name:_____________________________________

154

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #155 Page: 1 Name: _____________________________________

155

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #155 Page: 2 Name: _____________________________________

155

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -125,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -2,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10010010 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10111111 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10101000 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #155 Page: 3 Name: _____________________________________

155

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #155 Page: 4 Name: _____________________________________

155

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #155 Page: 5 Name:_____________________________________

155

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #155 Page: 6 Name: _____________________________________

155

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #155 Page: 7 Name: _____________________________________

155

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #155 Page: 8 Name:_____________________________________

155

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #156 Page: 1 Name: _____________________________________

156

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #156 Page: 2 Name: _____________________________________

156

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -41,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -111,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11010010 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11010110 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11011010 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #156 Page: 3 Name: _____________________________________

156

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #156 Page: 4 Name: _____________________________________

156

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #156 Page: 5 Name:_____________________________________

156

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #156 Page: 6 Name: _____________________________________

156

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #156 Page: 7 Name: _____________________________________

156

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #156 Page: 8 Name:_____________________________________

156

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #157 Page: 1 Name: _____________________________________

157

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #157 Page: 2 Name: _____________________________________

157

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -76,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -4,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10101011 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10001001 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11111001 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #157 Page: 3 Name: _____________________________________

157

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #157 Page: 4 Name: _____________________________________

157

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #157 Page: 5 Name:_____________________________________

157

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #157 Page: 6 Name: _____________________________________

157

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #157 Page: 7 Name: _____________________________________

157

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #157 Page: 8 Name:_____________________________________

157

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #158 Page: 1 Name: _____________________________________

158

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #158 Page: 2 Name: _____________________________________

158

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -100,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -67,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11011110 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 11100100 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10010001 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #158 Page: 3 Name: _____________________________________

158

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #158 Page: 4 Name: _____________________________________

158

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #158 Page: 5 Name:_____________________________________

158

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #158 Page: 6 Name: _____________________________________

158

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #158 Page: 7 Name: _____________________________________

158

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #158 Page: 8 Name:_____________________________________

158

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #159 Page: 1 Name: _____________________________________

159

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #159 Page: 2 Name: _____________________________________

159

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -96,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -7,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -89,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 11111000 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10011011 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 10110100 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #159 Page: 3 Name: _____________________________________

159

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #159 Page: 4 Name: _____________________________________

159

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #159 Page: 5 Name:_____________________________________

159

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #159 Page: 6 Name: _____________________________________

159

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #159 Page: 7 Name: _____________________________________

159

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #159 Page: 8 Name:_____________________________________

159

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100

1Exam #160 Page: 1 Name: _____________________________________

160

CS32—Midterm ExamE01, W15, Phill Conrad, UC Santa BarbaraWednesday, 04/30/2015, 9:30am­10:45am

Name: ___________________________________________________

Umail Address: ______________________________@ umail.ucsb.edu

Please write your name above AND AT THE TOP OF EVERY PAGEBe sure you turn in every page of this exam.

Each exam is numbered (e.g. Exam #137).Each pages is numbered (e.g. Page 1, Page 2, etc.)The last page clearly says "End of Exam".

This exam is closed book, closed notes, closed mouth, cell phone offYou are permitted one sheet of paper (max size 8.5x11") on which to write notesThese sheets will be collected with the exam, and might not be returnedPlease write your name on your notes sheet

2Exam #160 Page: 2 Name: _____________________________________

160

1. For these questions, assume 8-bit two's complement representation of negative integers. The left-most bit is the signbit, with 1 representing negative numbers, and 0 representing positive numbers.

a. (2 pts) Given the decimal number -95,what is this number's binary representation in 8-bit two's complement?

b. (2 pts) Given the decimal number -1,what is this number's binary representation in 8-bit two's complement?

c. (2 pts) Given the decimal number -124,what is this number's binary representation in 8-bit two's complement?

d. (2 pts) Given that 10100110 is the 8-bit two's complement representation of a number,what is that number in base ten?

e. (2 pts) Given that 10001110 is the 8-bit two's complement representation of a number,what is that number in base ten?

f. (2 pts) Given that 11000000 is the 8-bit two's complement representation of a number,what is that number in base ten?

3Exam #160 Page: 3 Name: _____________________________________

160

2. Suppose you have an array called a full of n integer values, indexed 0 through n-1. For simplicity, suppose there areno duplicates. You need to implement a function to return the index of a certain key value k if it occurs in the array,or -1 if it does not.

As we've discussed, two possible techniques are linear search (which our textbook calls serial search, and binarysearch.

a. (6 pts) Binary search places one additional requirement on the elements of the array. What is this additionalrequirement? It can be stated in a single sentence.

b. (6 pts) Assuming that the array a meets this additional requirement, describe how to apply the binary searchalgorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE OR PSEUDOCODE.Instead, describe the main idea of the algorithm in plain english. Though it is not required, if you wish, youmay make reference to a, n and k in your description.

c. (6 pts) Linear search has the advantage of not having this extra requirement, and is much easier to code andimplement correctly, but has a serious drawback as compared to binary search. Explain what that is. Again, itcan be stated in a single sentence—but for full credit, you must be as precise as possible in your answer.

d. (6 pts) Assuming that the array a does not meet the requirements for binary search, describe how to apply thelinear search algorithm to this problem. Be clear, precise, and concise. DO NOT WRITE CODE ORPSEUDOCODE. Instead, describe the main idea of the algorithm in plain english. Though it is not required,if you wish, you may make reference to a, n and k in your description.

4Exam #160 Page: 4 Name: _____________________________________

160

3. So far, our discussion of sorting has focused on two main sorting methods: insertion sort, and selection sort. Both ofthese can be implemented as an "in place" sort—one where the values are not copied anywhere outside the array,except to a single temporary variable.

As we've discussed, both of these sorting techniques can be implemented "in place" as successive passes, where thesorted array is built up at one end of the array or the other, in a series of n-1 steps. Our practice examples havefocussed on doing insertion sort where the sorted array is built left to right, and on selection sort, where the sortedarray is built right to left—but this is not the only possible implementation.

For each of the tables below, fill in the successive steps of the algorithm shown. The first two match what we'vedone before. The second two check whether you can adapt your understanding of how selection sort and insertionwork to a novel situation.

Grading for parts (a,b): ­1 for each incorrect entry, up to max of ­8Grading for parts (c,d): ­1 for each incorrect entry, up to max of ­4

a. (8 pts) Sort using insertion sort, building sorted array at start of array (at left, the way we've done it before):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

b. (8 pts) Sort using selection sort, building sorted array at end of array (at right, the way we've done it before.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

5 Exam #160 Page: 5 Name:_____________________________________

160

c. (4 pts) Sort using insertion sort, building sorted array at END of array (at right, the OPPOSITE of the waywe've done it before, but still using the approach used in insertion sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

d. (4 pts) Sort using selection sort, building sorted array at START of array (at left, the OPPOSITE of the waywe've done it before, but still using the approach used in selection sort.):

[0] [1] [2] [3] [4]33 29 48 17 6

         

         

         

6 17 29 33 48

6Exam #160 Page: 6 Name: _____________________________________

160

4. Most of the code we write in this course goes in files that end in .cpp. >But sometimes we worked with each of thefollowing types of files. For each type, explain what its purpose is, and its relationship to .cpp files.

DON'T USE TOO MANY WORDS. Write just enough to get the main point across. Excessively verbose answersthat stray off point may be penalized.

a. (4 pts) Purpose of .h files:

b. (4 pts) .h files relationship to .cpp files:

c. (4 pts) Purpose of .o files:

d. (4 pts) .o files relationship to .cpp files.

e. (4 pts) Purpose of Makefile:

f. (4 pts) Relationship of Makefile to .cpp files:

struct Node { int data; Node *next;} void printList(Node *head) { for (Node *p=head; p!=NULL; p=p->next) { cout << p->data << endl; }}

7Exam #160 Page: 7 Name: _____________________________________

160

5. At right is a fairly common definition fora C++ struct Node that can be used tomake a linked list of int values, along witha conventional implementation of afunction that prints the value of the linkedlist, one per line. As a homeworkassignment, you were asked to rewrite thefunction as a recursive function, i.e. to dothe same thing as this iterative version,but using recursion. BUT THAT'S NOTWHAT I'M ASKING YOU TO DO ONTHIS EXAM. So read carefully.

a. (10 pts) Write the definition of aC++ function calledprintListBackwards that also takes a Node *head as its parameter, and prints the list backwards.Given that the struct Node only has next pointers and no prev pointers, you might think this isimpossible, but with recursion is not only possible, it is trivially easy. (Well, if you understand recursion itis.)

HINT: If you are stuck, start by writing out the recursive version of printList which prints the listforwards using recursion. Then think about how you could tweak the function to print the list backwardsinstead.

THERE IS ONE MORE PROBLEM ON THE FINAL PAGE!

8 Exam #160 Page: 8 Name:_____________________________________

160

b. (6 pts) Given that there are no prev pointers, there is no straightforward way to print the list backwardswithout iteration that doesn't involve storing some amount of temporary data that is the same size as the listitself. For example, go might go through the list in the forward direction, and either store the data from thenodes in an array which you then iterate through backwards, or in another linked list that is built in theopposite diretion.

So how is it that this is possible with recursion? What is happening "under the hood" that makes thispossible? Briefly explain.

Hint: "activation record".

End of Examtotal points=100