#include<stdio.h>
int main()
{
int n,m=0;
printf("enter a number:");
scanf("%d",&n);
printf("your output:");
while (n){
switch (n%16) {
case 10 ...15: //...前必须有空格
printf("%c",'A'+n%16-10);
break;
default:
printf("%d",n%16);
}
n /= 16;
m++;
}
for (n=0; n<5-m; n++){
printf("%d",0);
}
return 0;
}