using System;

public class Program

{

    public static void Main()

    {

        char ch;

           Console.Write("\n\n");

           Console.Write("check whether the input alphabet is a vowel or not:\n");

           Console.Write("-----------------------------------------------------");

           Console.Write("\n\n");

​

           Console.Write("Input an Alphabet (A-Z or a-z) : ");

           ch = Convert.ToChar(Console.ReadLine().ToLower());

           int i=ch;

           if(i>=48 && i<=57)

           {

            Console.Write("You entered a number, Please enter an alpahbet."); 

            }

           else

           {           

           switch (ch)

           {

                case 'a':

                   Console.WriteLine("The Alphabet is vowel");

                   break;

               case 'i':

                   Console.WriteLine("The Alphabet is vowel");

                    break;

               case 'o':

                   Console.WriteLine("The Alphabet is vowel");

                   break;

               case 'u':

                   Console.WriteLine("The Alphabet is vowel");

                   break;

               case 'e':

                   Console.WriteLine("The Alphabet is vowel");

                   break;

               default:

                   Console.WriteLine("The Alphabet is not a vowel");

                   break;

           }

           }

    }

}