}
  }

  @Override
  @CheckForNull
  public Entry<E> firstEntry() {
    return delegate().firstEntry();
  }

  /**
   * A sensible definition of {@link #firstEntry()} in terms of {@code entrySet().iterator()}.
   *
   * <p>If you override {@link #entrySet()}, you may wish to override {@link #firstEntry()} to
   * forward to this implementation.
   */
  @CheckForNull

    }
  }

  @Override
  @CheckForNull
  public Entry<E> firstEntry() {
    return delegate().firstEntry();
  }

  /**
   * A sensible definition of {@link #firstEntry()} in terms of {@code entrySet().iterator()}.
   *
   * <p>If you override {@link #entrySet()}, you may wish to override {@link #firstEntry()} to
   * forward to this implementation.
   */
  @CheckForNull

    assertEquals(c, sortedMultiset.tailMultiset(b.getElement(), CLOSED).firstEntry());
    assertEquals(c, sortedMultiset.tailMultiset(c.getElement(), CLOSED).firstEntry());
  }

  @CollectionSize.Require(SEVERAL)
  public void testHigher() {
    resetWithHole();
    assertEquals(c, sortedMultiset.tailMultiset(a.getElement(), OPEN).firstEntry());

    assertEquals(c, sortedMultiset.tailMultiset(b.getElement(), CLOSED).firstEntry());
    assertEquals(c, sortedMultiset.tailMultiset(c.getElement(), CLOSED).firstEntry());
  }

  @CollectionSize.Require(SEVERAL)
  public void testHigher() {
    resetWithHole();
    assertEquals(c, sortedMultiset.tailMultiset(a.getElement(), OPEN).firstEntry());

  }

  @Override
  @CheckForNull
  public Entry<K, V> ceilingEntry(@ParametricNullness K key) {
    return tailMap(key, true).firstEntry();
  }

  @Override
  @CheckForNull
  public Entry<K, V> higherEntry(@ParametricNullness K key) {
    return tailMap(key, false).firstEntry();
  }

  @Override
  @CheckForNull
  public K lowerKey(@ParametricNullness K key) {
    return Maps.keyOrNull(lowerEntry(key));

    }
    Iterator<Entry<K, V>> iterator = map.entrySet().iterator();
    Entry<K, V> firstEntry = iterator.next();
    Entry<K, V> secondEntry = iterator.next();
    K key = secondEntry.getKey();
    SortedMap<K, V> subMap = map.tailMap(key);
    subMap.remove(key);
    assertNull(subMap.remove(firstEntry.getKey()));
    assertEquals(map.size(), oldSize - 1);
    assertFalse(map.containsKey(key));

  }

  @Override
  @CheckForNull
  public Entry<K, V> ceilingEntry(@ParametricNullness K key) {
    return tailMap(key, true).firstEntry();
  }

  @Override
  @CheckForNull
  public Entry<K, V> higherEntry(@ParametricNullness K key) {
    return tailMap(key, false).firstEntry();
  }

  @Override
  @CheckForNull
  public K lowerKey(@ParametricNullness K key) {
    return Maps.keyOrNull(lowerEntry(key));

   */
  @CheckForNull private transient int[] successor;

  /** Pointer to the first node in the linked list, or {@code ENDPOINT} if there are no entries. */
  private transient int firstEntry;

  /** Pointer to the last node in the linked list, or {@code ENDPOINT} if there are no entries. */
  private transient int lastEntry;

  CompactLinkedHashSet() {
    super();
  }

  }

  @Override
  int firstEntryIndex() {
    return firstEntry;
  }

  @Override
  int adjustAfterRemove(int indexBeforeRemove, int indexRemoved) {
    return (indexBeforeRemove >= size()) ? indexRemoved : indexBeforeRemove;
  }

  @Override
  public void clear() {
    if (needsAllocArrays()) {
      return;
    }
    this.firstEntry = ENDPOINT;
    this.lastEntry = ENDPOINT;

    super.resetMap(entries);
    navigableMap = (NavigableMap<K, V>) getMap();
  }

  @CollectionSize.Require(ZERO)
  public void testEmptyMapFirst() {
    assertNull(navigableMap.firstEntry());
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ZERO)
  public void testEmptyMapPollFirst() {
    assertNull(navigableMap.pollFirstEntry());
  }

  @CollectionSize.Require(ZERO)