@LazyInit @CheckForNull private transient Set<E> elementSet;

  @Override
  public Set<E> elementSet() {
    Set<E> result = elementSet;
    if (result == null) {
      elementSet = result = createElementSet();
    }
    return result;
  }

  /**
   * Creates a new instance of this multiset's element set, which will be returned by {@link
   * #elementSet()}.
   */
  Set<E> createElementSet() {

  }

  /**
   * Creates an {@code ArrayDeque} containing the elements of the specified iterable, in the order
   * they are returned by the iterable's iterator.
   *
   * @since 12.0
   */
  public static <E> ArrayDeque<E> newArrayDeque(Iterable<? extends E> elements) {
    if (elements instanceof Collection) {
      return new ArrayDeque<>((Collection<? extends E>) elements);
    }
    ArrayDeque<E> deque = new ArrayDeque<>();

    protected List<Byte> create(Byte[] elements) {
      return asList(elements);
    }
  }

  public static final class BytesAsListHeadSubListGenerator extends TestByteListGenerator {
    @Override
    protected List<Byte> create(Byte[] elements) {
      Byte[] suffix = {Byte.MIN_VALUE, Byte.MAX_VALUE};
      Byte[] all = concat(elements, suffix);
      return asList(all).subList(0, elements.length);
    }
  }

    protected List<Character> create(Character[] elements) {
      return asList(elements);
    }
  }

  public static final class CharsAsListHeadSubListGenerator extends TestCharListGenerator {
    @Override
    protected List<Character> create(Character[] elements) {
      Character[] suffix = {Character.MIN_VALUE, Character.MAX_VALUE};
      Character[] all = concat(elements, suffix);

    @Override
    protected List<Double> create(Double[] elements) {
      return asList(elements);
    }
  }

  public static final class DoublesAsListHeadSubListGenerator extends TestDoubleListGenerator {
    @Override
    protected List<Double> create(Double[] elements) {
      Double[] suffix = {Double.MIN_VALUE, Double.MAX_VALUE};
      Double[] all = concat(elements, suffix);
      return asList(all).subList(0, elements.length);

            + " even if some elements are null.",
        getSet().equals(MinimalSet.from(elements)));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_otherContainsNull() {
    Collection<E> elements = getSampleElements(getNumElements() - 1);
    elements.add(null);
    Set<E> other = MinimalSet.from(elements);

    assertFalse(

            + " even if some elements are null.",
        getSet().equals(MinimalSet.from(elements)));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_otherContainsNull() {
    Collection<E> elements = getSampleElements(getNumElements() - 1);
    elements.add(null);
    Set<E> other = MinimalSet.from(elements);

    assertFalse(

	}

	// As we add elements, len should grow.
	N := 32
	for i := 0; i < N; i++ {
		q.enqueue(i)
		if n := q.len; n != i+1 {
			t.Fatalf("after adding %d elements, queue has len %d", i, n)
		}
		if v, ok := q.peek(); !ok {
			t.Fatalf("couldn't peek after adding %d elements", i)
		} else if v.(int) != 0 {
			t.Fatalf("after adding %d elements, peek is %d; want 0", i, v)
		}
	}

    @Override
    protected List<String> create(String[] elements) {
      String[] suffix = {"f", "g"};
      String[] all = new String[elements.length + suffix.length];
      System.arraycopy(elements, 0, all, 0, elements.length);
      System.arraycopy(suffix, 0, all, elements.length, suffix.length);
      return ImmutableList.copyOf(all).subList(0, elements.length);
    }
  }

  }

  @Override
  Object[] internalArray() {
    return elements;
  }

  @Override
  int internalArrayStart() {
    return 0;
  }

  @Override
  int internalArrayEnd() {
    return elements.length;
  }

  @Override
  int copyIntoArray(@Nullable Object[] dst, int offset) {