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/* File : example.h */
#include <vector>
class Shape {
public:
Shape() {
nshapes++;
}
virtual ~Shape() {
nshapes--;
}
double x, y;
void move(double dx, double dy);
virtual double area(void) = 0;
virtual double perimeter(void) = 0;
static int nshapes;
};
class Circle : public Shape {
private:
double radius;
public:
Circle(double r) : radius(r) { }
virtual double area(void);
virtual double perimeter(void);
};
class Square : public Shape {
private:
double width;
public:
Square(double w) : width(w) { }
virtual double area(void);
virtual double perimeter(void);
};
Circle* createCircle(double w); // this method creates a new object
Square* createSquare(double w); // this method creates a new object
class ShapeOwner {
private:
std::vector<Shape*> shapes;
ShapeOwner(const ShapeOwner&); // no copying
ShapeOwner& operator=(const ShapeOwner&); // no copying
public:
ShapeOwner();
~ShapeOwner();
void add(Shape* ptr); // this method takes ownership of the object
Shape* get(int idx); // this pointer is still owned by the class (assessor)
Shape* remove(int idx); // this method returns memory which must be deleted
};
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