struct point {
   float  x, y;
};

class Polygon {
public:
   Polygon(int);             // constructor
   Polygon(char*);           // constructor
   Polygon(const Polygon&);  // copy constructor
   ~Polygon();               // destructor
   void translate(float,float);
   void scale(float,float);
   void rotate(float);
   void draw();
private:
   point *vertices, centre;
   int   num_vertices;
};