Contraseña como cadena - Ejercicio de Programacion C# Sharp

using System;  // Import the System namespace to use basic classes like Console

class Program  // Define the main class of the program
{
    static void Main()  // The entry point of the program
    {
        string username;  // Declare a variable to store the username
        string password;  // Declare a variable to store the password

        // Loop until the correct username and password are entered
        do
        {
            // Ask the user for their username
            Console.Write("Enter your username: ");
            username = Console.ReadLine();  // Read the username input from the user

            // Ask the user for their password
            Console.Write("Enter your password: ");
            password = Console.ReadLine();  // Read the password input from the user

            // Check if the username and password are correct
            if (username != "username" || password != "password")  // If either is incorrect
            {
                Console.WriteLine("Invalid username or password, please try again.");  // Display error message
            }

        } while (username != "username" || password != "password");  // Repeat until both are correct

        // When correct username and password are entered
        Console.WriteLine("Welcome! You have successfully logged in.");  // Welcome message
    }
}

 Salida

Case 1:
Enter your username: user1
Enter your password: 1234
Invalid username or password, please try again.
Enter your username: username
Enter your password: password
Welcome! You have successfully logged in.

Case 2:
Enter your username: admin
Enter your password: admin123
Invalid username or password, please try again.
Enter your username: username
Enter your password: password
Welcome! You have successfully logged in.