using System;

​

public class Program

{

    public static void Main()

    {

        String a = "Pawan";

        String b = "PAWAN";

        switch (string.Compare(a, b, StringComparison.InvariantCultureIgnoreCase))

        {

            case 1:

                Console.WriteLine("a is greater");

                break;

            case 0:

                Console.WriteLine("a and b are equal");

                break;

            case -1:

                Console.WriteLine("b is greater");

                break;

        }

    }

}