template <typename N> class Point {
private: 
  double x, y;

public:
  Point(double, double);
  Point();
  double getx () const;
  double gety () const;

  double distance_to(Point<N>);
  bool less_than(const Point<N>&);
};

template <typename N> std::ostream& operator<<(std::ostream&, const Point<N>&);