using System;

​

namespace dhinagaran 

{

    public class dhina 

    {

         public static void Main()

         {

             Console.WriteLine("Enter Your Mark");

             int num = Convert.ToInt32(Console.ReadLine());

            if ( num < 0 || num > 100)

            {

                Console.WriteLine("This is wrong number");

            }

            else if (num >= 0 && num <= 50  )

            {

                Console.WriteLine("This Member is fail");

            }

            else if (num >= 51 && num <= 75)

            {

                Console.WriteLine("Grade B ");

            }

            else if ( num >= 76 && num <= 100) 

            {

                Console.WriteLine("Grade A ");

            }

         }

    }

}

​