프로그래머라면 1001 1001단

진정한 프로그래머라면 1001 1001단 입니다. ㅎㅎ
외워봅시다!,(구구단의 2진수 버전입니다. 자세한건 소스코드에)

=====================
1 * 1 = 1
1 * 10 = 10
1 * 11 = 11
1 * 100 = 100
1 * 101 = 101
1 * 110 = 110
1 * 111 = 111
1 * 1000 = 1000
1 * 1001 = 1001
=====================
10 * 1 = 10
10 * 10 = 100
10 * 11 = 110
10 * 100 = 1000
10 * 101 = 1010
10 * 110 = 1100
10 * 111 = 1110
10 * 1000 = 10000
10 * 1001 = 10010
=====================
11 * 1 = 11
11 * 10 = 110
11 * 11 = 1001
11 * 100 = 1100
11 * 101 = 1111
11 * 110 = 10010
11 * 111 = 10101
11 * 1000 = 11000
11 * 1001 = 11011
=====================
100 * 1 = 100
100 * 10 = 1000
100 * 11 = 1100
100 * 100 = 10000
100 * 101 = 10100
100 * 110 = 11000
100 * 111 = 11100
100 * 1000 = 100000
100 * 1001 = 100100
=====================
101 * 1 = 101
101 * 10 = 1010
101 * 11 = 1111
101 * 100 = 10100
101 * 101 = 11001
101 * 110 = 11110
101 * 111 = 100011
101 * 1000 = 101000
101 * 1001 = 101101
=====================
110 * 1 = 110
110 * 10 = 1100
110 * 11 = 10010
110 * 100 = 11000
110 * 101 = 11110
110 * 110 = 100100
110 * 111 = 101010
110 * 1000 = 110000
110 * 1001 = 110110
=====================
111 * 1 = 111
111 * 10 = 1110
111 * 11 = 10101
111 * 100 = 11100
111 * 101 = 100011
111 * 110 = 101010
111 * 111 = 110001
111 * 1000 = 111000
111 * 1001 = 111111
=====================
1000 * 1 = 1000
1000 * 10 = 10000
1000 * 11 = 11000
1000 * 100 = 100000
1000 * 101 = 101000
1000 * 110 = 110000
1000 * 111 = 111000
1000 * 1000 = 1000000
1000 * 1001 = 1001000
=====================
1001 * 1 = 1001
1001 * 10 = 10010
1001 * 11 = 11011
1001 * 100 = 100100
1001 * 101 = 101101
1001 * 110 = 110110
1001 * 111 = 111111
1001 * 1000 = 1001000
1001 * 1001 = 1010001
=====================

아래는 간단히 만들어본 소스코드..ㅎㅎ
( 소스코드 링크 - http://hkpco.kr/code/programmer.c )

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define SIGN1 printf(" * ");
#define SIGN2 printf(" = ");

int dec2bin( int n );

int main( void )
{
int c1, c2, r;

for( c1 = 1 ; c1 < 10 ; c1++ )
{
printf("=====================\n");
for( c2 = 1 ; c2 < 10 ; c2++ )
{
r = c1 * c2;
dec2bin(c1); SIGN1 dec2bin(c2); SIGN2 dec2bin(r);
printf("\n");
}
}
printf("=====================\n");
}
int dec2bin( int n )
{
if( n == 0 )
{
return 0;
}
else
{
dec2bin(n/2);
printf( "%d" , (n%2) ? 1 : 0 );
}
}