using System;

using static System.Console;

using System.Collections.Generic;

​

var isPasswordValid = "no";

int outInt = 0;

WriteLine("Enter the username you want to use for the site");

var userName = ReadLine();

while (isPasswordValid == "no")

{

    WriteLine("Enter the password you want to use for the site.");

    WriteLine("Entry must be at least 10 characters, ending with a number and containing at least one special character $, # or &");

    var password = ReadLine();

    bool isLastCharNumeric = int.TryParse(password[password.Length - 1].ToString(), out outInt);

    if (password.Length < 10 || !isLastCharNumeric || (!password.Contains("$") && !password.Contains("#") && !password.Contains("&")))

    {

        WriteLine("Password is invalid!  Please try again!");

        if (password.Length < 10)

        {

            WriteLine("**Password entered is not at least 10 characters.");

        }

​

        if (!isLastCharNumeric)

        {

            WriteLine("**Password entered does not end with a number.");

        }

​

        if (!password.Contains("$") && !password.Contains("#") && !password.Contains("&"))

        {

            WriteLine("**Password entered does not contain one of the following special characters $#&");

        }

​

        WriteLine("");

    }

    else

    {

        WriteLine("Thank you!  Site registration is complete.");

        isPasswordValid = "yes";

    }

}