#include <iostream>
#include <list>
#include <vector>
#include <string>
#include <stdio.h>
#include <stdint.h>
#include <iomanip>
using namespace std;

using uint = unsigned int;
using ll = long long;

#define CIN( LL , A ) LL A; cin >> A 
#define GETLINE( A ) string A; getline( cin , A ) 
#define FOR_ITR( ARRAY , ITR , END ) for( auto ITR = ARRAY .begin() , END = ARRAY .end() ; ITR != END ; ITR ++ ) 

int main()
{

  CIN( string , T );
  const string colon = ":";
  bool b = false;
  ll h = 0;
  ll m = 0;

  for( uint i = 0 ; i < 5 ; i++ ){

    const string c = T.substr( i , 1 );

    if( c == colon ){

      b = true;

    } else {

      if( b ){

	m = m * 10 + stoi( c );

      } else {

	h = h * 10 + stoi( c );

      }      

    }

  }

  const ll time = h * 60 + m + 5;
  const string answer = to_string( ( time / 60 ) % 24 + 100 ).substr( 1 ) + colon + to_string( time % 60 + 100 ).substr( 1 );
  cout << answer << endl;
  return 0;

}