using System;

public class Program

{

    public static void Main()

    {

            Console.WriteLine("Enter Number");

            int num;

            if (! int.TryParse(Console.ReadLine(), out num))

            {

                Console.WriteLine("Enter Valid");

            }

     switch(num)

     {

         case 1:

         Console.WriteLine("Enter 1");

         case 2:

         Console.WriteLine("Enter 2");

         break;

         default:

         Console.WriteLine("Enter nothing ");

         break;

     }

    }

    private static bool IsPrime(int num)

    {

        if(num == 1)

        {

            return false;

        }

        if(num == 2)

        {

            return true;

        }

        else

        {

            for(int i = 2; i<num; i++)

            {

                if(num % i == 0)

                    return false;

            }

            return true;

        }

    }

}