```cpp
#include<bits/stdc++.h>
using namespace std;
double s,v,m;
int n,a,t,b;
int main()
{
cin>>s>>v;
n=8*60+24*60;
t=ceil(s/v)+10;
n=n-t;
if(n>=24*60) n-=24*60;
b=n%60;
a=n/60;
if(a<10)
{
if(b<10) cout<<"0"<<a<<":0"<<b;
else cout<<"0"<<a<<":"<<b;
}
else
{
if(b<10) cout<<a<<":0"<<b;
else cout<<a<<":"<<b;
}
return 0;
}
```
by chenhaoyu987 @ 2022-04-21 13:03:53
@[zps1122](/user/578842)
```
#include<bits/stdc++.h>
using namespace std;
int main(){
float s=0,v=0;
cin>>s>>v;
int a=int(ceil(s/v)<=470?470-ceil(s/v):1910-ceil(s/v))/60,b=int(ceil(s/v)<=470?470-ceil(s/v):1910-ceil(s/v))%60;
a<10?b<10?cout<<"0"<<a<<":0"<<b:cout<<"0"<<a<<":"<<b:b<10?cout<<a<<":0"<<b:cout<<a<<":"<<b;
}
```
by Nagligivaget @ 2022-04-22 19:20:06
@[zps1122](/user/578842)
绝对最短
by Nagligivaget @ 2022-04-22 19:21:18