public class Point
{
    //state for our Point
    private final int x;// final= not reassignable
    private final int y;
    public Point(int x, int y)
    {
        this.x = x;
        this.y = y; 
    }
    public Point()
    {
        this(0,0);  //calls sibling constructor
    }
    public Point reflectionAcrossX()
    {
        return new Point(x, -y);
    }
    @Override
    public String toString()
    {
        return String.format("(%s, %s)", x, y);
    }
    public double distanceTo(Point that)
    {
        return Math.hypot(x - that.x, y - that.y);
    }
    public  static void main(String[] args)
    {
        Point p = new Point(3,4);
        System.out.println(p);
        System.out.println(p.reflectionAcrossX());
        Point origin = new Point();
        System.out.println(p.distanceTo(origin));
        System.out.println("Naughtinesss");
        p.x = 12;
        System.out.println(p);
    }
}