using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("您好，停車費每小時40元，消費累積500元可折抵1小時，請輸入您的停車時數：");

        string x = Console.ReadLine();

        int time = int.Parse(x);

        Console.WriteLine("停車費總共");

        Console.WriteLine(time*40);

        Console.WriteLine("請問您今日是否有在館內消費(y/n)");

        string answer = Console.ReadLine();

        if (answer == "n")

        {

            Console.WriteLine("您本次的停車費為");

            Console.WriteLine(time*40);

        }

        else

        {

        string receipt = "y";

        int discount = 0;

        while (receipt == "y")

        {

            Console.WriteLine("請輸入您的發票金額：");

            int price = int.Parse(Console.ReadLine());

            discount = discount + price;;

            Console.WriteLine("請問是否還有消費發票金額(y/n)");

            receipt = Console.ReadLine();

        }

            int final = (time-(discount/500))*40;

            if (final <= 0)

            {

                Console.WriteLine("您本次的停車費為0元");

        }

            else

            {

                Console.WriteLine("您本次的停車費為");

                Console.WriteLine(final);

        }

   }

}

}