sumseconds

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

namespace sumseconds
{
    class Program
    {
        static void Main(string[] args)
        {
            int a = int.Parse(Console.ReadLine());
            int b = int.Parse(Console.ReadLine());
            int c = int.Parse(Console.ReadLine());

            int seconds = a + b + c;
            int minutes = 0;


            if (seconds<=0 && seconds<=59)
            {
                minutes = 0;

            }
            else if (seconds>=60 && seconds <=119)
            {
                minutes = 1;
                seconds = seconds - 60;

            }
            else if (seconds>= 120 && seconds <= 179)
            {
                minutes = 2;
                seconds = seconds - 120;

            }
            if (seconds < 10)
            {
                Console.WriteLine(minutes + ":0" + seconds);
            }
            else
                Console.WriteLine(minutes + ":" + seconds);
        }
    }
}