#include<iostream.h> class Shape { protected: int width, height; public: Shape( int a=0, int b=0) { width = a; height = b; } int area() { cout << "Parent class area :" <<endl; return 0; } }; class Rectangle: public Shape{ public: Rectangle( int a=0, int b=0):Shape(a, b) { } int area () { cout << "Rectangle class area :" <<endl; return (width * height); } }; class Triangle: public Shape{ public: Triangle( int a=0, int b=0):Shape(a, b) { } int area () { cout << "Triangle class area :" <area(); // store the address of Triangle shape = &tri; // call triangle area. shape->area(); return 0; }