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

namespace Sum_Seconds
{
    class Program
    {
        static void Main(string[] args)
        {
            int time1 = int.Parse(Console.ReadLine());
            int time2 = int.Parse(Console.ReadLine());
            int time3 = int.Parse(Console.ReadLine());

            int time = time1 + time2 + time3;

            if (time >= 0 && time <= 59)
            {
                Console.WriteLine("0:0" + time);
            }
            else if (time >= 60 && time <= 119)

            {
                Console.WriteLine("1:0" + (time - 60));
            }
            else if (time >= 120 && time <= 179)

            {
                Console.WriteLine("2:0" + (time - 120));
            }
            else if (time < 10)
            {
                Console.WriteLine("0:0"+time);
            }

        }
    }
}