南昌大学航天杯第二届程序设计竞赛校赛网络同步赛 小q的时钟

#include <bits/stdc++.h>

#define ll long long

using namespace std;

int main()

{

ll begin,end,time;

ll hh,mm,ss;

while(~scanf("%lld %lld",&begin,&end))

{

time=end-begin;

hh=time/(3600);

time=time%3600;

mm=time/60;

ss=time%60;

printf("%02lld:%02lld:%02lld\n",hh,mm,ss);

}

return 0;

}