將一個十進制整數轉換爲二進制並輸出

 1  #include <stdio.h>
 2  #include <string.h>
 3  
 4  int main(int argc, char *argv[])
 5  {
 6          char bin[8 * sizeof(int)];
 7          int n = 0;
 8          int index;
 9  
10          scanf("%d", &n);
11  
12          for(index = (8 * sizeof(int) - 1); index >= 0; index--)
13          {
14                  bin[index] = (n & 1) + '0';
15                  n >>= 1;
16          }
17 
18         bin[8 * sizeof(int)] = '\0';
19          int i = 0;
20 
21         for(index = 0; index <= (8 * sizeof(int) - 1); index++)
22         {
23             ++i;
24             putchar(bin[index]);
25 
26             if(i % 4 == 0)
27             {
28                 putchar(' ');
29             }
30         }
31            putchar('\n');
32   
33            return 0;
34 }