#include<bits/stdc++.h> using namespace std; int main(){ int s,v,min=0,hour=0; cin>>s>>v; if(s%v==0){ min=s/v; } else{ min=(s-s%v)/v+1; } while(min>=60){ hour+=1; min-=60; } hour=7-hour; min=50-min; if(hour>=0) printf("%02d:%02d",hour,min); }