public class Point3Testbed {
  public static void main(String[] argv) {
    Point3 pt1 = new Point3(), pt2 = new Point3(100), pt3 = new Point3(40, 80, 120);
    System.out.println("pt1:");
    pt1.print();
    System.out.println("pt2:");
    pt2.print();
    System.out.println("pt3:");
    pt3.print();
  }
}