#include<bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
  string s;
  cin>>s;
  //cout<<s.substr(0,2)<<" "<<s.substr(3,2)<<endl;
  int h=stoll(s.substr(0,2));
  int m=stoll(s.substr(3,2));
  m+=5;
  if(m>=60) m-=60,h++;
  if(h==24) h=0;
  printf("%02d:%02d\n",h,m);
  return 0;
}