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)
        {
            var time = int.Parse(Console.ReadLine());
            var time1 = int.Parse(Console.ReadLine());
            var time2 = int.Parse(Console.ReadLine());

            int result = time + time1 + time2;

            if (result < 59 && result > 10)
            {
                Console.WriteLine("0:" + result);
            }
            else if (result < 119 && result >= 60)
            {
                Console.WriteLine("1:" + (result - 60));
            }
            else if (result >= 120 && result < 179)
            {
                Console.WriteLine("2:" + (result - 120));
            }
            else if (result < 10)
            {
                Console.WriteLine("0:0" + result);
            }


        }
    } }