using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace YukiCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            var va = Console.ReadLine().Split(':').Select(int.Parse).ToArray();
            int nn = va[0] * 60 + va[1] + 5;
            int nH = nn / 60 % 24;
            int nM = nn % 60;
            Console.WriteLine(nH.ToString("D02") + ":" + nM.ToString("D02"));
            Console.ReadLine();
        }
    }
}