example.h 611 B

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  1. /* File : example.h */
  2. class Shape {
  3. public:
  4. Shape() {
  5. nshapes++;
  6. }
  7. virtual ~Shape() {
  8. nshapes--;
  9. };
  10. double x, y;
  11. void move(double dx, double dy);
  12. virtual double area(void) = 0;
  13. virtual double perimeter(void) = 0;
  14. static int nshapes;
  15. };
  16. class Circle : public Shape {
  17. private:
  18. double radius;
  19. public:
  20. Circle(double r) : radius(r) { };
  21. virtual double area(void);
  22. virtual double perimeter(void);
  23. };
  24. class Square : public Shape {
  25. private:
  26. double width;
  27. public:
  28. Square(double w) : width(w) { };
  29. virtual double area(void);
  30. virtual double perimeter(void);
  31. };