class Point implements Serializable, Cloneable {

    public static double distance(double x1, double y1, double x2, double y2) {
        return Math.sqrt(distanceSq(x1, y1, x2, y2));
    }

    public  Point();
    public  Point(int x, int y);
    public  Point(double x, double y);
    public  Point(Point p);

}