#include <stdlib.h>
#include <stdio.h>
#include <string>
#include <iostream>

using namespace std;

class Shape {
protected:
    int width, height;
public:
    Shape(int a = 0, int b = 0) {
        width = a;
        height = b;
    }

    virtual void area() {
        cout << "Parent class area" << endl;
    }
};

class Rectangle : public Shape {
public:
    Rectangle(int a = 0, int b = 0) : Shape(a, b) {}

    void area() {
        cout << "Rectangle class area : " << (width * height) << endl;
    }
};

class Triangle : public Shape {
public:
    Triangle(int a = 0, int b = 0) : Shape(a, b) {}

    void area() {
        cout << "Triangle class area : " << (width * height / 2) << endl;
    }
};

int main()
{
    Shape *shape[4];
    Rectangle r1(5,3);
    Rectangle r2(25,7);
    Triangle t1(2, 6);
    Triangle t2(7, 9);

    shape[0] = &r1;
    shape[1] = &r2;
    shape[2] = &t1;
    shape[3] = &t2;

    for (int i = 0; i < 4; i++)
    {
        (*shape[i]).area();
    }

    system("PAUSE");
    return 0;
}