#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
  int A,B;
  cin>>A>>B;
  char a,b,c;
  cin>>a>>b>>c;
  int T = 60*A+B+2340;
  double S;
  cin>>S;
  T += (int)(60*S);
  T %= 1440;
  if(T/60 < 10) cout<<0;
  cout<<T/60<<':';
  if(T%60 < 10) cout<<0;
  cout<<T%60<<endl;
}