POLYMORPHISM

#include <iostream>
using namespace std;

class Shape
{
protected:
    int width, height;

public:
    Shape(int a, int b)
    {
        width = a;
        height = b;
    }
    virtual int area() = 0;
};
// Rectangle : -
class Rectangle : public Shape{
    public :
        Rectangle(int a, int b) : Shape(a, b){}
        int area()
        {
        cout << "Rectangle class area :" << (width * height) << endl;
        }
};
// Triangle : -

class Triangle : public Shape
{
public:
    Triangle(int a, int b) : Shape(a, b) {}
    int area()
    {
        cout << "Triangle class area :" << (width * height / 2) << endl;
    }
};
int main()
{
    Shape *shape;
    Rectangle rec(20, 14);
    Triangle tri(20, 10);
    // store the address of rectangle
    shape = &rec;
    // call rectangle area.
    shape->area();
    // store the address of triangle
    shape = &tri;
    // call triangle area.
    shape->area();
    return 0;
}