using System;

public class Program

{

    public static void Main()

    {

        string decision;

        do 

        {

            Console.WriteLine("Welcome To Club House");

            Console.WriteLine("Are You Member of Club House:- Yes or No");

            decision= Console.ReadLine().ToUpper();

            if (decision != "YES" && decision!="NO");

            {

                Console.WriteLine("You Have Entered Invalid Character {0}",decision);

            }

        }while (decision != "YES" &&  decision !="NO");

        while (decision.ToUpper()!="YES");

        Console.WriteLine("Thank YOu For Viewing Our Website");

    }

}