code: public Container iandNot(Container x) {
      if (x instanceof ArrayContainer) {
        return iandNot((ArrayContainer) x);
      } else if (x instanceof BitmapContainer) {
        return iandNot((BitmapContainer) x);
      }
      return iandNot((RunContainer) x);
    }
docs: Computes the in-place bitwise ANDNOT of this container with another (difference). The current
  container is generally modified, whereas the provided container (x) is unaffected. May generate
  a new container.
  
  @param x other container
  @return aggregated container