using System;

using System.Globalization;     

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        string blin = "okt";

        string line = "OKt";

        Console.WriteLine(blin == line ? "TRUE" : "FALSE");

        Console.WriteLine(blin == line.ToUpper() ? "TRUE" : "FALSE");

        Console.WriteLine(blin == line.ToLower() ? "TRUE" : "FALSE");

​

    }

}