权威

#include<iostream>
#include<algorithm>
using namespace std;
int main(){
    int t;
    scanf("%d",&t);
    if(t/3600<10){
        printf("%d",0);
    }
    printf("%d%c",t/3600,':');
    if(t%3600/60<10){
        printf("%d",0);
    }
    cout<<t%3600/60<<":";
    if(t%3600%60<10){
        printf("%d",0);
    }
    printf("%d",t%3600%60);    
    return 0;
}