// Defines a base class named Customer
// And a child class FrequentCustomer who receives a discount
// Main program demonstrates a customer of each type
using System;
public class DebugEight01
{
    public static void Main()
    {
        Customer aRegularCustomer = new Customer();
        FrequentCustomer aFrequentCustomer = new FrequentCustomer();

        aRegularCustomer.CustNum = 2514;
        aRegularCustomer.CustBalance = 765.00;
        aFrequentCustomer.CustNum = 5719;
        aFrequentCustomer.CustBalance = 2500.00;
        aFrequentCustomer.DiscountRate = 0.15;
        Console.WriteLine("\naRegularCustomer #{0} owes {1}",
           aRegularCustomer.CustNum,
           Convert.ToInt32(aRegularCustomer.CustBalance));
        Console.WriteLine("\naFrequentCustomer #{0} would owe {1} without the discount",
           aFrequentCustomer.CustNum,
           aFrequentCustomer.CustBalance.ToString("C2"));
        double newBal = (1 - aFrequentCustomer.DiscountRate) *
           aFrequentCustomer.CustBalance;
        Console.WriteLine("...with {0} discount, customer owes {1}",
           aFrequentCustomer.DiscountRate.ToString("P"), newBal.ToString("C"));

    }
}
public class Customer
{
    private int custNum;
    private double custBalance;
    public int CustNum // it was int before
    {
        get
        {
            return custNum;
        }
        set
        {
            custNum = value;
        }
    }
    public double CustBalance
    {
        get
        {
            return custBalance;
        }
        set
        {
            custBalance = value;
        }
    }
}
class FrequentCustomer : Customer
{
    private double discountRate;
    public double DiscountRate
    {
        get
        {
            return discountRate;
        }
        set
        {
            discountRate = value;
        }
    }
    public new int CustNum
    {
        get
        {
            return base.CustNum;
        }
        set
        {
            CustNum = value;
        }
    }
}