Bitset

 1 #include <stdio.h> 
 2  
 3 int main(){
 4     int number;
 5     char result[20];
 6     int length;
 7     int i;
 8     
 9     while((scanf("%d",&number))!=EOF){
10         i=0;
11         while(number){
12             result[i]=number%2+‘0‘;
13             i++;
14             number/=2;
15         }
16         length=i;
17         
18         for(i=length-1;i>=0;i--)
19             printf("%c",result[i]);
20             
21         printf("\n");
22     }
23         
24     return 0;
25 }