assertEquals(ImmutableSortedSet.of(4), Sets.subSet(set, Range.open(2, 6)));
    assertEquals(ImmutableSortedSet.of(4, 6), Sets.subSet(set, Range.open(3, 7)));
    assertEquals(empty, Sets.subSet(set, Range.open(20, 30)));

    assertEquals(set, Sets.subSet(set, Range.openClosed(0, 12)));
    assertEquals(ImmutableSortedSet.of(2, 4), Sets.subSet(set, Range.openClosed(0, 4)));

  private final transient Reference<AvlNode<E>> rootReference;
  private final transient GeneralRange<E> range;
  private final transient AvlNode<E> header;

  TreeMultiset(Reference<AvlNode<E>> rootReference, GeneralRange<E> range, AvlNode<E> endLink) {
    super(range.comparator());
    this.rootReference = rootReference;
    this.range = range;
    this.header = endLink;
  }

  TreeMultiset(Comparator<? super E> comparator) {

          RangeMap<Integer, Integer> rangemap =
              ImmutableRangeMap.<Integer, Integer>builder().put(range1, 1).put(range2, 2).build();
          assertEquals(range1.span(range2), rangemap.span());
        }
      }
    }
  }

  public void testGetEntry() {
    for (Range<Integer> range1 : RANGES) {
      for (Range<Integer> range2 : RANGES) {

   * {@code to}] for all {@code i} in the range [{@code requiredFrom}, {@code requiredTo}]. The
   * value returned by this method is the {@code i} in that range such that {@code allRequired[i]}
   * is as close as possible to the center of the range [{@code from}, {@code to}]. Choosing the
   * value closest to the center of the range first is the most efficient strategy because it

    TreeRangeSet<Integer> set = TreeRangeSet.create();
    Range<Integer> range = Range.closedOpen(0, 5);
    set.subRangeSet(range).add(range);
  }

  public void testSubRangeSetReplaceAdd() {
    TreeRangeSet<Integer> set = TreeRangeSet.create();
    Range<Integer> range = Range.closedOpen(0, 5);
    set.add(range);
    set.subRangeSet(range).add(range);
  }

  public void testComplement() {

   * range sets a and b, the result of {@code a.add(range)} is that {@code a} will be the minimal
   * range set for which both {@code a.enclosesAll(b)} and {@code a.encloses(range)}.
   *
   * <p>Note that {@code range} will be {@linkplain Range#span(Range) coalesced} with any ranges in
   * the range set that are {@linkplain Range#isConnected(Range) connected} with it. Moreover, if
   * {@code range} is empty, this is a no-op.

   * range set.
   */
  private ImmutableList<Range<C>> intersectRanges(final Range<C> range) {
    if (ranges.isEmpty() || range.isEmpty()) {
      return ImmutableList.of();
    } else if (range.encloses(span())) {
      return ranges;
    }

    final int fromIndex;
    if (range.hasLowerBound()) {
      fromIndex =

   * range set.
   */
  private ImmutableList<Range<C>> intersectRanges(final Range<C> range) {
    if (ranges.isEmpty() || range.isEmpty()) {
      return ImmutableList.of();
    } else if (range.encloses(span())) {
      return ranges;
    }

    final int fromIndex;
    if (range.hasLowerBound()) {
      fromIndex =

    }
  }

  @Override
  public Range<K> span() {
    if (ranges.isEmpty()) {
      throw new NoSuchElementException();
    }
    Range<K> firstRange = ranges.get(0);
    Range<K> lastRange = ranges.get(ranges.size() - 1);
    return Range.create(firstRange.lowerBound, lastRange.upperBound);
  }

  /**
   * Guaranteed to throw an exception and leave the {@code RangeMap} unmodified.

        range.intersect(GeneralRange.<@Nullable Integer>range(ORDERING, null, OPEN, 5, CLOSED)));

    assertEquals(
        GeneralRange.range(ORDERING, 2, OPEN, 4, OPEN),
        range.intersect(GeneralRange.range(ORDERING, 2, OPEN, 5, CLOSED)));

    assertEquals(
        GeneralRange.range(ORDERING, 2, CLOSED, 4, OPEN),
        range.intersect(GeneralRange.range(ORDERING, 1, OPEN, 4, OPEN)));
  }