using System;

public class Program

{

    public static void Main()

    {

​

        // Q1

        Console.WriteLine("Enter first string: ");

        string input1 = Console.ReadLine();

        Console.WriteLine("Enter second string: ");

        string input2 = Console.ReadLine();

        // clean inputs

        input1 = input1.ToLower();

        input2 = input2.ToLower();

        input1 = input1.Trim();

        input2 = input2.Trim();

        // compare

        if (input1 == input2) 

        {

            Console.WriteLine("Equal");

        } else {

            Console.WriteLine("Not Equal");

        }

        // Q2

        string str = "Celebrating 200 year of Indiana University";

        int idx1 = str.IndexOf("r");

        int idx2 = str.IndexOf("r", idx1 + 1);

        str = str.Insert(idx2 + 1, "s");

        Console.WriteLine(str);

​

    }

}