//------------------------------------------------------------------------------

struct Arrow : Closed_polyline {

    Arrow(Point p1, Point p2);    // upper left, min, and max distance from center

    //void draw_lines() const;

};

//------------------------------------------------------------------------------

struct Reg_polygon : Closed_polyline {

    Reg_polygon(int sides, Point p1, double radius);    // number of sides, center and distance from center

    //void draw_lines() const;

};