Question

Question 3: Q3 (Polymorphism & virtual function) a) Consider the class, derived class, and the virtual functions as shown in Display for Q3. Create a derived class (of Sale) called 'MailorderSale' having one private member variable called 'shipping charge'. It should have constructor function and virtual function 'bill' (this function adds shipping charge to the price). Define all these functions (no need of default constructors). b) In the main function, define one object of DiscountSale with (11,10) initial values and define another object of MailorderSale with (8, 2) initial values. Then write statements to compare their bills using overload operator '<' and print appropriate messages.

Answer 1

C++ code:

#include "stdafx.h"

#include <iostream>

using namespace std;

//base class Sale

class Sale

{

//variable and function declaration

public:

double price;

public:

//constructor

Sale(double p)

{

   price = p;

}

virtual void bill(){};

};

//Derived class

class MailorderSale : public Sale

{

private:

double shipping_charge;

public:

MailorderSale(double p, double sc) : Sale(p)

{

   shipping_charge = sc;

}

void bill()

{

   price = price + shipping_charge;

};

};

//Class for Discount

class DiscountSale : public Sale

{

private:

double discount;

public:

DiscountSale(double p, double d):Sale(p)

{

discount = d;

}

void bill()

{

price = price - discount;

};

};

//main

int main()

{

    DiscountSale discount(11,10);

   MailorderSale mail(8,2);

   if ( mail.price < discount.price)

   {

       cout << "\n Mailorder price less than Discount price" << endl;

   }

   else

   {

       cout << "\nMailorder price greater than or equal to Discount price" << endl;

   }

    system("pause");

    return 0;

}

Output:

Mailorder price less than Discount price Press any key to continue . -