Sum Seconds

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

namespace DomashnoSumSeconds
{
    class Program
    {
        static void Main(string[] args)
        {
            int TimeFirst = int.Parse(Console.ReadLine());
            int TimeSecond = int.Parse(Console.ReadLine());
            int TimeThird = int.Parse(Console.ReadLine());
            int TotalTime = TimeFirst + TimeSecond + TimeThird;
            int Minutes = TotalTime / 60;
            int Seconds = TotalTime % 60;
            if (Seconds < 10)
            {
                Console.WriteLine($"{Minutes}:0{Seconds}");
            }
            else
            {
                Console.WriteLine($"{Minutes}:{Seconds}");
            }
        }
    }
}