return wrap(getSortedSetDelegate().descendingSet());
    }

    @Override
    public Iterator<V> descendingIterator() {
      return new WrappedIterator(getSortedSetDelegate().descendingIterator());
    }

    @Override
    public NavigableSet<V> subSet(
        @ParametricNullness V fromElement,
        boolean fromInclusive,
        @ParametricNullness V toElement,

            }
          }
          return elemItr.next();
        }
      };
    }

    @Override
    @GwtIncompatible("NavigableSet")
    public UnmodifiableIterator<C> descendingIterator() {
      return new AbstractIterator<C>() {
        final Iterator<Range<C>> rangeItr = ranges.reverse().iterator();
        Iterator<C> elemItr = emptyIterator();

        @Override

  @Override
  public @Nullable E lower(E e) {
    return Iterators.<@Nullable E>getNext(headSet(e, false).descendingIterator(), null);
  }

  /**
   * @since 12.0
   */
  @Override
  public @Nullable E floor(E e) {
    return Iterators.<@Nullable E>getNext(headSet(e, true).descendingIterator(), null);
  }

  /**
   * @since 12.0
   */
  @Override
  public @Nullable E ceiling(E e) {

      iterator.remove();
      fail("UnsupportedOperationException expected");
    } catch (UnsupportedOperationException expected) {
    }
    try {
      Iterator<Integer> iterator = unmod.descendingIterator();
      iterator.next();
      iterator.remove();
      fail("UnsupportedOperationException expected");
    } catch (UnsupportedOperationException expected) {
    }
  }