using System;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("What lesson?");

        int myYear;

        //implicit conversion can only happen when you don't want to lose data 

        try

        {

            myYear = Convert.ToInt16(Console.ReadLine());

        }

        catch

        {

            Console.WriteLine("You can only answer using numbers");

            myYear = 0;

        }

​

        switch (myYear)

        {

            case 1:

                Console.WriteLine("Starts at 09:10 and ends at 10:10");

                break;

            case 2:

                Console.WriteLine("Starts at 10:20 and ends at 11:20");

                break;

            case 3:

                Console.WriteLine("Starts at 11:40 and ends at 12:40");

                break;

            case 4:

                Console.WriteLine("Starts at 12:50 and ends at 13:50");

                break;

            case 5:

                Console.WriteLine("Starts at 14:30 and ends at 15:25");

                break;

            default:

                Console.WriteLine("(Said in an Irish accent) Why the frick did you just $%^£$$%%^%£$£%$£$&&%&%£!£%<>?@%&^. . . you're so STUPID!!");

                break;

        }

    }

}