三拳击碎你的坤坤梦

#include<bits/stdc++.h>
using namespace std;
int n;
int main(){
    cin>>n;
    if(n/3600<10)cout<<"0";
    cout<<n/3600<<":";
    if(n%3600/60<10)cout<<"0";
    cout<<n%3600/60<<":";
    if(n%60<10)cout<<"0";
    cout<<n%60;
}