Entry<Cut<K>, RangeMapEntry<K, V>> lastEntry = entriesByLowerBound.lastEntry();
    // Either both are null or neither is, but we check both to satisfy the nullness checker.
    if (firstEntry == null || lastEntry == null) {
      throw new NoSuchElementException();
    }
    return Range.create(
        firstEntry.getValue().getKey().lowerBound, lastEntry.getValue().getKey().upperBound);
  }

    return delegate.isEmpty();
  }

  @Override
  public NavigableSet<K> keySet() {
    return navigableKeySet();
  }

  @Override
  public @Nullable Entry<K, V> lastEntry() {
    return delegate.lastEntry();
  }

  @Override
  public K lastKey() {
    return delegate.lastKey();
  }

  @Override
  public @Nullable Entry<K, V> lowerEntry(K key) {

      long lastEntry = entries[srcIndex];
      entries[dstIndex] = lastEntry;
      entries[srcIndex] = UNSET;

      // also need to update whoever's "next" pointer was pointing to the last entry place
      // reusing "tableIndex" and "next"; these variables were no longer needed
      int tableIndex = getHash(lastEntry) & hashTableMask();
      int lastNext = table[tableIndex];

    // entry object per key.
    private ValueSetLink<K, V> firstEntry;
    private ValueSetLink<K, V> lastEntry;

    ValueSet(@ParametricNullness K key, int expectedValues) {
      this.key = key;
      this.firstEntry = this;
      this.lastEntry = this;
      // Round expected values up to a power of 2 to get the table size.

    return delegate.isEmpty();
  }

  @Override
  public NavigableSet<K> keySet() {
    return navigableKeySet();
  }

  @Override
  public @Nullable Entry<K, V> lastEntry() {
    return delegate.lastEntry();
  }

  @Override
  public K lastKey() {
    return delegate.lastKey();
  }

  @Override
  public @Nullable Entry<K, V> lowerEntry(K key) {

      return new StandardElementSet();
    }

    @Override
    public Entry<E> firstEntry() {
      return standardFirstEntry();
    }

    @Override
    public Entry<E> lastEntry() {
      return standardLastEntry();
    }

    @Override
    public Entry<E> pollFirstEntry() {
      return standardPollFirstEntry();
    }

    @Override
    public Entry<E> pollLastEntry() {

  }

  @Override
  @CheckForNull
  public Entry<E> firstEntry() {
    return isEmpty() ? null : getEntry(0);
  }

  @Override
  @CheckForNull
  public Entry<E> lastEntry() {
    return isEmpty() ? null : getEntry(length - 1);
  }

  @Override
  public int count(@CheckForNull Object element) {
    int index = elementSet.indexOf(element);
    return (index >= 0) ? getCount(index) : 0;

    Entry<Cut<K>, RangeMapEntry<K, V>> lastEntry = entriesByLowerBound.lastEntry();
    // Either both are null or neither is, but we check both to satisfy the nullness checker.
    if (firstEntry == null || lastEntry == null) {
      throw new NoSuchElementException();
    }
    return Range.create(
        firstEntry.getValue().getKey().lowerBound, lastEntry.getValue().getKey().upperBound);
  }

      return new StandardElementSet();
    }

    @Override
    public Entry<E> firstEntry() {
      return standardFirstEntry();
    }

    @Override
    public Entry<E> lastEntry() {
      return standardLastEntry();
    }

    @Override
    public Entry<E> pollFirstEntry() {
      return standardPollFirstEntry();
    }

    @Override
    public Entry<E> pollLastEntry() {

  @CheckForNull
  public Entry<K, V> lowerEntry(K key) {
    return headMap(key, false).lastEntry();
  }

  @Override
  @CheckForNull
  public K lowerKey(K key) {
    return keyOrNull(lowerEntry(key));
  }

  @Override
  @CheckForNull
  public Entry<K, V> floorEntry(K key) {
    return headMap(key, true).lastEntry();
  }

  @Override
  @CheckForNull
  public K floorKey(K key) {