Time + 15

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

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


            var plus15 = minutes + 15;

            if (plus15 <= 59)
            {
                Console.WriteLine("{0}:{1:D2}", hour, plus15);
            }
            else if (plus15 > 59)
            {
                Console.WriteLine("{0}:{1:D2}", (hour + 1) % 24, plus15 - 60);
            }
        }
    }
}