OnTimeForExam

using System;

namespace _1OnTimeforExam
{
    class Program
    {
        static void Main(string[] args)
        {
            int ExamHour = int.Parse(Console.ReadLine());
            int ExamMin = int.Parse(Console.ReadLine());
            int ArriveHour = int.Parse(Console.ReadLine());
            int ArriveMin = int.Parse(Console.ReadLine());

            string early = "Early";
            string ontime = "On time";
            string late = "Late";

            var examtime = (ExamHour * 60) + ExamMin;
            var arrivetime = (ArriveHour * 60) + ArriveMin;

            var totaldifference = arrivetime - examtime;

            if (totaldifference > 0)
            {
                if (totaldifference <= 59)
                {
                    Console.WriteLine(late);
                    Console.WriteLine("{0} minutes after the start", totaldifference);
                }
                else if (totaldifference >= 60)
                {
                    Console.WriteLine(late);
                    Console.WriteLine("{0}:{1:00} hours after the start", (arrivetime - examtime) / 60, (arrivetime - examtime) % 60);
                }
            }

            if (totaldifference < 0)
            {
                if (Math.Abs(totaldifference) <= 30)
                {
                    Console.WriteLine(ontime);
                    Console.WriteLine("{0} minutes before the start", Math.Abs(totaldifference));
                }
                else if (Math.Abs(totaldifference) > 30 && Math.Abs(totaldifference) <= 59)
                {
                    Console.WriteLine(early);
                    Console.WriteLine("{0} minutes before the start", Math.Abs(totaldifference));
                }
                else if (Math.Abs(totaldifference) >= 60)
                {
                    Console.WriteLine(early);
                    Console.WriteLine("{0}:{1:00} hours before the start", (examtime - arrivetime) / 60, (examtime - arrivetime) % 60);
                }
            }
            else if (totaldifference == 0)
            { Console.WriteLine(ontime); }

        }
    }
}