using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Entrez votre username : ");

        string username = "elsassian";

        string usernameEnter = Console.ReadLine();

        Console.WriteLine("Entrez votre password : ");

        string password = "0987654321";

        string passwordEnter = Console.ReadLine();

        if (usernameEnter == username)

        {

            if (passwordEnter == password)

            {

                Console.WriteLine("Welcome back " + username);

            }

        }

        else 

        {

            Console.WriteLine("Error : the username or/and the password is/are wrong");

        }

        Console.WriteLine("What do you want to do ?");

        Console.Write("press q to quit");

        if (Console.ReadKey().Key == ConsoleKey.Q)

        {

        }

    }

}