// comparison list
for (int i = 0; i < 100; i++) {
int x = rand.nextInt(MAX_X);
int y = rand.nextInt(MAX_Y);
Point p = new Point(x, y);
tracker.addObject(x, y, p);
points.add(p);
}
// now choose 100 new random points and confirm that the tracker
// reports the same closest point that our brute force check