using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("請輸入使用者名稱：");

        string username = Console.ReadLine();

​

        if(username == "馬壯")

        {

            Console.WriteLine(username+"您好");

            Console.WriteLine("請輸入密碼：");

            string password = Console.ReadLine();

                if((password == "egg566")||(password == "EGG566"))

                {

                    Console.WriteLine("歡迎進入本系統");

                }

                else

                {

                Console.WriteLine("密碼錯誤");

                }

        }

        else if (username=="徐強" )

             {

            Console.WriteLine(username+"您好");

            Console.WriteLine("請輸入密碼：");

            string password = Console.ReadLine();

            if((password == "dog123") || (password == "Dog123") || (password == "DOG123"))

                {

                Console.WriteLine("歡迎進入本系統");

                }

            else

            {

                Console.WriteLine("密碼錯誤");

            }

            }

        else

        {

            Console.WriteLine("本系統不認識"+username);

        }

    }

}