#include <iostream>
#include <cmath>
using namespace std;
class Shape
{
  public:
    Shape(){}
    ~Shape(){}
  public:
    virtual double getArea() const = 0;
    virtual double getPerim() const = 0;
  private:
};
class Rectangle : public Shape
{
  public:
    Rectangle(double _length, double _width) : length(_length), width(_width){}
    ~Rectangle(){}
  public:
    double getArea() const {return length * width;}
    double getPerim() const {return 2 * (length + width);}
  private:
    double length;
    double width;
};
class Circle : public Shape
{
  public:
    Circle(double _radius) : radius(_radius){}
    ~Circle(){}
  public:
    double getArea() const {return radius * radius * M_PI;}
    double getPerim() const {return 2 * M_PI * radius;}
  private:
    double radius;
};
int main()
{
  Rectangle * rec = new Rectangle(2, 3);
  Circle * cir = new Circle(3);
  cout << rec->getArea() << endl;
  cout << rec->getPerim() << endl;
  cout << cir->getArea() << endl;
  cout << cir->getPerim() << endl;
  return 0;
}

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