using System;

​

public class Program

{

    public static void Main()

    {

        int hours = int.Parse(Console.ReadLine());

        int minutes = int.Parse(Console.ReadLine());

        minutes += 15;

        if (minutes >= 60)

        {

            minutes -= 60;

            hours++;

        }

​

        if (hours == 24)

        {

            hours = 0;

        }

​

        if (minutes < 10)

        {

            Console.WriteLine(hours + ":0" + minutes);

        }

        else

        {

            Console.WriteLine(hours + ":" + minutes);

        }

    }

}