public class Punto {
	    private final double x; 
	    private final double y; 
	   
	    public Punto() {x = 0.0; y = 0.0;}
	    public Punto(double x, double y) {this.x = x;this.y = x; }

	    public double x() { return x; }
	    public double y() { return y; }
	    
	    public double distanzaDa(Punto p) {
	        double dx = this.x() - x();
	        double dy = this.y() - y();
	        return Math.sqrt(dx*dx + dy*dy);
	    }

	    public String toString() { return "(" + x + ", " + y + "}";  } 

}