Time Plus 15 Min

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

namespace DomashnoTimePlus15Min
{
    class Program
    {
        static void Main(string[] args)
        {
            // get exact time

            int HourNow = int.Parse(Console.ReadLine());
            int MinutesNow = int.Parse(Console.ReadLine());

            // convert exact time to minutes

            int MinutesAfterMidnight = HourNow * 60 + MinutesNow;

            // add 15 min to converted

            int MinutesAfterMidnight15MinLater = MinutesAfterMidnight + 15;

            // calculate Hour after 15 min and convert if it is 24

            int HourAfter15Min = MinutesAfterMidnight15MinLater / 60;
            if (HourAfter15Min == 24)
            {
                HourAfter15Min = 0;
            }


            // calculate minutes after 15 min

            int MinutesAfter15Min = MinutesAfterMidnight15MinLater % 60;

            // print if MinutesAfter15Min<10 with leading 0

            if (MinutesAfter15Min < 10)
            {
                Console.WriteLine($"{HourAfter15Min}:0{MinutesAfter15Min}");
            }
            else
            {
                Console.WriteLine($"{HourAfter15Min}:{MinutesAfter15Min}");
            }
        }
    }
}