编辑代码

#include <stdio.h>
int main () 
{
    int a,b,x,y,z;
    scanf("%d",&a);
    b=a%3600;
    x=a/3600;
    z=b%60;
    y=b/60;
    printf("%d:%.2d:%.2d\n",x,y,z);
}