+15 mins exercise

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

namespace issue16_1
{
    class Program
    {
        static void Main(string[] args)
        {

            int a = int.Parse(Console.ReadLine());
            int b = int.Parse(Console.ReadLine());
            TimeSpan span = new TimeSpan(a, b, 0);
            TimeSpan span2 = TimeSpan.FromMinutes(15);
            TimeSpan duration = span.Add(span2);
            Console.WriteLine(duration.ToString("h\\:mm"));
        }
    }
}