题解 | 小乐乐定闹钟

using System;
public class Program {
    public static void Main() {
        string[] str = Console.ReadLine().Split();
        string[] str1 = str[0].Split(':');
        int hour = int.Parse(str1[0]);
        int minute = int.Parse(str1[1]);
        int n = int.Parse(str[1]);
        int hour1 =  (hour + (n + minute) / 60) % 24;
        int minute1 = (n + minute) % 60;
        Console.WriteLine("{0:d2}:{1:d2}", hour1 , minute1);
    }
}