dynamic allocation and polymorphism : Polymorphism « Class « C++

1. C++
2. Class
3. Polymorphism

dynamic allocation and polymorphism

  
#include <iostream>
using namespace std;

class CPolygon {
  protected:
    int width, height;
  public:
    void set_values (int a, int b)
    { width=a; height=b; }
    virtual int area (void) =0;
    void printarea (void)
    { cout << this->area() << endl; }
  };

class CRectangle: public CPolygon {
  public:
    int area (void)
    { return (width * height); }
};

class CTriangle: public CPolygon {
  public:
    int area (void)
    { return (width * height / 2); }
};

int main () {
  CPolygon * ppoly1 = new CRectangle;
  CPolygon * ppoly2 = new CTriangle;
  ppoly1->set_values (4,5);
  ppoly2->set_values (4,5);
  ppoly1->printarea();
  ppoly2->printarea();
  delete ppoly1;
  delete ppoly2;
  return 0;
}
  
    
  

Related examples in the same category

1.	Use virtual functions and polymorphism.
2.	Object array: polymorphism.
3.	An example that uses typeid on a polymorphic class hierarchy
4.	Polymorphism with base class pointer