public static void test(Point a, Point b) {
        Point c = new Point(b.x, a.y);
        int ac = Math.abs(a.x - c.x);
        int bc = Math.abs(b.y - c.y);
        double ab = Math.sqrt(ac * ac + bc * bc);
        System.out.println(Math.asin(bc / ab) * 180 / Math.PI);
    }