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/* File : example.c */
#include "example.h"
#include <stdio.h>
#define M_PI 3.14159265358979323846
/* Move the shape to a new location */
void Shape::move(double dx, double dy) {
x += dx;
y += dy;
}
int Shape::nshapes = 0;
double Circle::area(void) {
return M_PI*radius*radius;
}
double Circle::perimeter(void) {
return 2*M_PI*radius;
}
double Square::area(void) {
return width*width;
}
double Square::perimeter(void) {
return 4*width;
}
Circle* createCircle(double w)
{
return new Circle(w);
}
Square* createSquare(double w)
{
return new Square(w);
}
ShapeOwner::ShapeOwner() {printf(" ShapeOwner(%p)\n",this);}
ShapeOwner::~ShapeOwner()
{
printf(" ~ShapeOwner(%p)\n",this);
for(unsigned i=0;i<shapes.size();i++)
delete shapes[i];
}
void ShapeOwner::add(Shape* ptr) // this method takes ownership of the object
{
shapes.push_back(ptr);
}
Shape* ShapeOwner::get(int idx) // this pointer is still owned by the class (assessor)
{
if (idx < 0 || idx >= static_cast<int>(shapes.size()))
return NULL;
return shapes[idx];
}
Shape* ShapeOwner::remove(int idx) // this method returns memory which must be deleted
{
if (idx < 0 || idx >= static_cast<int>(shapes.size()))
return NULL;
Shape* ptr=shapes[idx];
shapes.erase(shapes.begin()+idx);
return ptr;
}
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