#include <bits/stdc++.h>
#define int long long 
using namespace std;

signed main() {
  string T;
  cin >> T;
  
  int H = stoi(T.substr(0,2));
  int M = stoi(T.substr(3,2));
  M += 5;
  if( M >= 60 ){
    M -= 60;
    H++;
  }
  if( H == 24 ) H = 0;
  
  string h = to_string(H);
  if( H < 10 ) h = "0"+h;
  string m = to_string(M);
  if( M < 10 ) m = "0"+m;
  cout << h << ":" << m << endl;
}