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

namespace Time15min
{
    class Program
    {
        static void Main(string[] args)
        {
            int hours = int.Parse(Console.ReadLine());
            int minutes = int.Parse(Console.ReadLine());

            int totalMinutes = hours * 60 + minutes + 15;
            int totalHours = totalMinutes / 60;

            TimeSpan result = TimeSpan.FromMinutes(totalMinutes);
            string stringresult = result.ToString("h':'mm");

            Console.WriteLine(stringresult);

        }
    }
}