@Override
  public boolean containsAll(@NotNull Collection<?> c) {
    Object[] elements = get();
    int len = elements.length;
    for (Object e : c) {
      if (indexOf(e, elements, 0, len) < 0) {
        return false;
      }
    }
    return true;
  }
@Override
  public boolean containsAll(@NotNull Collection<?> c)