class Dimension {

  private final int width;
  private final int height;

  public Dimension(int width, int height) {
    if (width < 0 || height < 0) {
      throw new IllegalArgumentException();
    }
    this.width = width;
    this.height = height;
  }

  public int getWidth() {
    return width;
  }

  public int getHeight() {
    return height;
  }

  @Override
  public boolean equals(Object other) {<FILL_FUNCTION_BODY>}

  @Override
  public int hashCode() {
    return width * 32713 + height;
  }

  @Override
  public String toString() {
    return width + "x" + height;
  }

}

    if (other instanceof Dimension) {
      Dimension d = (Dimension) other;
      return width == d.width && height == d.height;
    }
    return false;
  
<no_super_class>