class ColorPoint extends Point {
    int color;
    ColorPoint(int x, int y, int color) {
      super(x, y);
      this.color = color;
    }
    public boolean equals(Object o) {
      if (o instanceof ColorPoint) {
        if (!o.getClass().isAssignableFrom(getClass())) {
          //let the subclass decide if we are equal
          return o.equals(this);
        }
        ColorPoint cp = (ColorPoint)o;
        return color == cp.color && super.equals(o);
      }
      return false;
    }

    public int hashCode() {
      return x*31 + y*29 + color*37;
    }
    public String toString() {
        return ("ColorPoint: x = " + x + ", y = " + y + ", color = " + color);
    }
}