C

C Express

C Express

4

4 C Express 2012 All rights reserved * * * * * * * .4 C Express 2012 All rights reserved Q) (variable) ?A) Q) ?A) .789056

124 C Express 2012 All rights reserved = .7i int 4 C Express 2012 All rights reserved .

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44 C Express 2012 All rights reserved (Q) ?100 0 (A) . .

100 0 .. 102 ?

4 C Express 2012 All rights reserved (variable):

(constant): () 3.14, 100, A, Hello World!12124 C Express 2012 All rights reserved 1 : 2 : 3 : Q&A

* () : 7 (Q) ? . (literal) . . .literal ) true, false

MAX_SIZE4 C Express 2012 All rights reserved: /* */#include int main(void){

float radius;// float area;// printf(" :");scanf("%f", &radius);

area = 3.141592 * radius * radius;printf(" : %f \n", area);

return 0;}

:10 : 314.159210 4 C Express 2012 All rights reserved (data type): ()

() short, int, long: (100) () double, float: (3.141592)() char: (A, a, )

4 C Express 2012 All rights reserved (Q) ? .

* ,, .

.

.4 C Express 2012 All rights reserved

4 C Express 2012 All rights reserved char short int float double long double

4 C Express 2012 All rights reserved: #include

int main(void){ int x;

printf(" x : %d", sizeof(x)); printf("char : %d", sizeof(char)); printf("int : %d", sizeof(int)); printf("short : %d", sizeof(short)); printf("long : %d", sizeof(long)); printf("float : %d", sizeof(float)); printf("double : %d", sizeof(double)); return 0; }

x : 4char : 1int : 4short : 2long : 4float : 4double : 84 C Express 2012 All rights reserved shortshort 2-3276832767int4-21474836482147483647longlong 4-21474836482147483647unsigned short short 2065535unsigned int 404294967295unsigned long long 404294967295char 1-128127unsigned char 10255float 41.2E-383.4E38double 82.2E-3081.8E308long double 82.2E-3081.8E3084 C Express 2012 All rights reserved15

(identifier): 7x x 100sum sum 4 C Express 2012 All rights reserved , _ _ C . (Q) ?sum_countking3n_pictures2nd_tryDollor#doubleOOOOX// X// #X// Animationeffect 4 C Express 2012 All rights reserved : bank_account :BankAccount a, b, c, ,d,number, average, sum,4 C Express 2012 All rights reserved(keyword): C (reserved words) .auto double int struct breakelse long switch caseenum register typedef char extern return union constfloat short unsigned continuefor signed void defaultgoto sizeof volatile do if static while 4 C Express 2012 All rights reserved

int index; int index 4 C Express 2012 All rights reserved

char c;int i;double interest_rate;int height, width;double interest_ratechar cint iint int heightwidth4 C Express 2012 All rights reserved char c;// c int i;// i double interest_rate;// interest_rate

c = 'a';// c 'a' i = 60;// i 60 interest_rate = 4.9;// interest_rate 82.9 achar 74.9double interest_rateint ci4 C Express 2012 All rights reserved = ; char c = a;int i = 7;double interest_rate = 0.05;a70.05double interest_ratechar cint i4 C Express 2012 All rights reserved

C .int main(void) { int i;//

printf("Hello World!\n"); int sum; // } 4 C Express 2012 All rights reserved 1 : , 2 : , 3 : 24 .

int value;value = 10;value = 20;4 C Express 2012 All rights reserved .

int value1 = 10;int value2;value2 = value1;4 C Express 2012 All rights reserved: #include

int main(void){int usd;// int krw;//

printf(" : ");scanf("%d", &usd);

krw = 1120 * usd;printf(" %d %f.", usd, krw);

return 0;}

: 100 100 112000. 4 C Express 2012 All rights reservedshort, int, long int CPU .16, 32, 64 (Q) ?(A) shortintlong16(2)32(4)32(4)4 C Express 2012 All rights reserved short grade;// short . int count;// int . long distance;// distance .

4 C Express 2012 All rights reserved int

short

long int -21 +214 C Express 2012 All rights reserved/* */ #include

int main(void) { short year = 0;// 0 . int sale = 0;// 0 . long total_sale = 0;// 0 .

year = 10;// 32 sale = 200000000;// 21 total_sale = year * sale;// 21 printf("total_sale = %d \n", total_sale);

return 0; }

Total sale = 2000000004 C Express 2012 All rights reservedsigned, unsigned unsigned unsigned int

signed

shortintlong4 C Express 2012 All rights reservedunsigned unsigned int speed;// int unsigned distance;// unsigned int distance .unsigned short players;// shortunsigned long seconds;// long4 C Express 2012 All rights reserved(overflow):

intint2147483648overflow4 C Express 2012 All rights reserved#include #include

int main(void){short s_money = SHRT_MAX;// . 32767unsigned short u_money = USHRT_MAX; // . 65535

s_money = s_money + 1;printf("s_money = %d", s_money);

u_money = u_money + 1;printf("u_money = %d", u_money);return 0;} !!

assasas_money = -32768u_money = 04 C Express 2012 All rights reserved 1 : 2 : 3 :

35 . 2147483646-32768-32767...327663276701...6553465535shortunsigned short4 C Express 2012 All rights reserved int . sum = 123; // 123 int

.sum = 123L; // 123 long

u Uunsigned int 123u 123Ul Llong123l 123Lul ULunsigned long123ul 123UL4 C Express 2012 All rights reserved

10, 8, 1610

int x = 10; int y = 012;// 8int z = 0xA; // 16

4 C Express 2012 All rights reserved /* */ #include

int main(void) { int x = 10; // 10 10 int 10. int y = 010; // 010 8 int 8. int z = 0x10; // 010 16 int 16.

printf("x = %d", x); printf("y = %d", y); printf("z = %d", z);

return 0; }

x = 10y = 8z = 164 C Express 2012 All rights reserved (symbolic constant): () area = 3.141592 * radius * radius; area = PI * radius * radius;

income = salary - 0.15 * salary;income = salary - TAX_RATE * salary;

. .4 C Express 2012 All rights reserved40

4 C Express 2012 All rights reserved #1#define EXCHANGE_RATE 1120

EXCHANGE_RATE 1120 4 C Express 2012 All rights reserved #2const int EXCHANGE_RATE = 1120;

1120EXCHANGE_RATE .

const 4 C Express 2012 All rights reserved: #include #define TAX_RATE 0.2

int main(void){const int MONTHS = 12;int m_salary, y_salary;//

printf( " : ");// scanf("%d", &m_salary);y_salary = MONTHS * m_salary;// printf(" %d.", y_salary);printf(" %f.", y_salary*TAX_RATE);

return 0;}

: 100 1200. 240.000000.4 C Express 2012 All rights reserved .

001010004 C Express 2012 All rights reserved 1 : 0 2 : 3 : 1 , 45 . . .

4 C Express 2012 All rights reserved . , .() +3 + (-3)

.

Animationeffect 4 C Express 2012 All rights reserved . . 3-3 = 3+(-3)4 C Express 2012 All rights reserved 2 . -> 2

Animationeffect 4 C Express 2012 All rights reserved2 2 .

Animationeffect 4 C Express 2012 All rights reserved /* 2 */ #include

int main(void) { int x = 3; int y = -3;

printf("x = %08X\n", x);// 8 16 . printf("y = %08X\n", y);// 8 16 . printf("x+y = %08X\n", x+y);// 8 16 .

return 0; } 2 .x = 00000003 y = FFFFFFFD x+y = 00000000 Animationeffect 4 C Express 2012 All rights reserved

4 C Express 2012 All rights reserved #1 32 16, 16

4 C Express 2012 All rights reserved #2

.10-38 10+38

4 C Express 2012 All rights reserved

floatdoublelong double