#include<iostream>
using namespace std;
int main()
{
    int s,v,t,m,h;
    cin>>s>>t;
    if(s%v==0) t=s/t+10;
    else t=int(s/t)+11;
    h=int(t/60);
    m=int(t%60);
    cout<<0<<(8-h)<<":";
    if(m<10) cout<<0<<m;
    else cout<<m;
    return 0;
}

全是re