using System;
public class Program {
    public static void Main() {
        string[] s = Console.ReadLine().Split(" ");
        string[] str = s[0].Split(":");
        int[] ints = 字符数组转整型数组(str);
        int met = int.Parse(s[1]);
        ints[0] += met / 60;
        ints[1] += met % 60;
        if (ints[1] >= 60)
        {
            ints[0]++;
            ints[1] -= 60;
        }
        Console.WriteLine("{0:D2}:{1:D2}",ints[0]%24 , ints[1]);
}

static int[] 字符数组转整型数组(string[] s) {
    int[] arr = new int[s.Length];
    for (int i = 0; i < s.Length; i++) {
        arr[i] = int.Parse(s[i]);
    }
    return arr;
}
}