In this article I will share to you how to write a C++ program to demonstrate object-oriented programming using C++.

I am currently accepting programming work, IT projects, school and application development, programming projects, thesis and capstone projects, IT consulting work, computer tutorials, and web development work kindly contact me at the following email address for further details.  If you want to advertise on my website kindly contact me also in my email address also. Thank you.

My email address is the following jakerpomperada@gmail.com, jakerpomperada@aol.com, and jakerpomperada@yahoo.com.

My mobile number here in the Philippines is 09173084360.

Please subscribe to my channel  https://www.youtube.com/channel/UCOs-lpOoIeJoh6gpJthPoGg

=================================================



You can buy my C++ book online at  



Beginner’s Guide To C++ Programming
You can buy my book in introduction to computer networking at https://www.unlimitedbooksph.com/product-page/introduction-to-computer-networking Want to support my channel? GCash Account Jake Pomperada 09173084360 Paypal https://paypal.me/jakerpomperada Patreon https://www.patreon.com/jakerpomperada Thank you very much for your support.

Program Listing

#include <iostream>
#include <cmath>
#include <iomanip>


class Shape {
public:
    virtual double calculateArea() = 0; // Pure virtual function, making the class abstract
};

class Rectangle : public Shape {
private:
    double width;
    double height;

public:
    Rectangle(double w, double h) : width(w), height(h) {}

    double calculateArea() override {
        return width * height;
    }
};

class Circle : public Shape {
private:
    double radius;

public:
    Circle(double r) : radius(r) {}

    double calculateArea() override {
        return M_PI * radius * radius;
    }
};

class Triangle : public Shape {
private:
    double base;
    double height;

public:
    Triangle(double b, double h) : base(b), height(h) {}

    double calculateArea() override {
        return 0.5 * base * height;
    }
};

int main() {
    Rectangle rect(8.0, 2.0);
    Circle circle(4.2);
    Triangle triangle(4.0, 7.0);

    Shape* shapes[] = {&rect, &circle, &triangle};

    std::cout << "\n\tShapes Using OOP in C++\n\n";

    for (Shape* shape : shapes) {
        std::cout << "\tArea: " <<std::fixed <<std::setprecision(2) << shape->calculateArea() << std::endl;
    }
    std::cout << "\n\tEnd of Program\n";
    return 0;
}