16進数 → 2進数 変換
再作成することがあるので記載。
#include <stdio.h>
#include <string.h>
int main(void)
{
char hex;
char binary[5];
scanf("%c", &hex);
switch(hex)
{
case '0':
strcpy(binary, "0000");
break;
case '1':
strcpy(binary, "0001");
break;
case '2':
strcpy(binary, "0010");
break;
case '3':
strcpy(binary, "0011");
break;
case '4':
strcpy(binary, "0100");
break;
case '5':
strcpy(binary, "0101");
break;
case '6':
strcpy(binary, "0110");
break;
case '7':
strcpy(binary, "0111");
break;
case '8':
strcpy(binary, "1000");
break;
case '9':
strcpy(binary, "1001");
break;
case 'a':
case 'A':
strcpy(binary, "1010");
break;
case 'b':
case 'B':
strcpy(binary, "1011");
break;
case 'c':
case 'C':
strcpy(binary, "1100");
break;
case 'd':
case 'D':
strcpy(binary, "1101");
break;
case 'e':
case 'E':
strcpy(binary, "1110");
break;
case 'f':
case 'F':
strcpy(binary, "1111");
break;
}
printf("%s", binary);
return 0;
}