ImmutableSet.Builder<String> builder = ImmutableSet.builderWithExpectedSize(4);
    builder.add("a");
    assertEquals(1, builder.size);
    builder.add("a");
    assertEquals(1, builder.size);
    builder.add("b", "c", "d");
    assertEquals(4, builder.size);
    Object[] table = builder.hashTable;
    assertNotNull(table);
    assertSame(table, ((RegularImmutableSet<String>) builder.build()).table);
  }

    return CollectSpliterators.indexed(size(), SPLITERATOR_CHARACTERISTICS, this::get);
  }

  @Override
  int copyIntoArray(@Nullable Object[] dst, int offset) {
    // this loop is faster for RandomAccess instances, which ImmutableLists are
    int size = size();
    for (int i = 0; i < size; i++) {
      dst[offset + i] = get(i);
    }
    return offset + size;
  }

  /**

      builder.add(i % setSize);
    }
    ImmutableSet<Integer> set = builder.build();
    assertTrue(set instanceof RegularImmutableSet);
    assertEquals(
        "Input size " + inputSize + " and set size " + setSize,
        tableSize,
        ((RegularImmutableSet<Integer>) set).table.length);
  }

  public void testCopyOf_copiesImmutableSortedSet() {

  static final int MAX_TABLE_SIZE = Ints.MAX_POWER_OF_TWO;

  // Represents how tightly we can pack things, as a maximum.
  private static final double DESIRED_LOAD_FACTOR = 0.7;

  // If the set has this many elements, it will "max out" the table size
  private static final int CUTOFF = (int) (MAX_TABLE_SIZE * DESIRED_LOAD_FACTOR);

  /**

    Builder<K, V> combine(Builder<K, V> other) {
      checkNotNull(other);
      ensureCapacity(this.size + other.size);
      System.arraycopy(
          other.alternatingKeysAndValues,
          0,
          this.alternatingKeysAndValues,
          this.size * 2,
          other.size * 2);
      this.size += other.size;
      return this;
    }

    private ImmutableMap<K, V> build(boolean throwIfDuplicateKeys) {

      return forwardList;
    }

    private int reverseIndex(int index) {
      int size = size();
      checkElementIndex(index, size);
      return (size - 1) - index;
    }

    private int reversePosition(int index) {
      int size = size();
      checkPositionIndex(index, size);
      return size - index;
    }

    @Override
    public void add(int index, @ParametricNullness T element) {

    // the stream.
    for (int bufSize = initialBufferSize;
        totalLen < MAX_ARRAY_LEN;
        bufSize = IntMath.saturatedMultiply(bufSize, bufSize < 4096 ? 4 : 2)) {
      byte[] buf = new byte[min(bufSize, MAX_ARRAY_LEN - totalLen)];
      bufs.add(buf);
      int off = 0;
      while (off < buf.length) {
        // always OK to fill buf; its size plus the rest of bufs is never more than MAX_ARRAY_LEN

      newDelegate.addAll(delegate);
      this.table = newDelegate;
      return;
    }
    int size = this.size;
    if (size < requireEntries().length) {
      resizeEntries(size);
    }
    int minimumTableSize = CompactHashing.tableSize(size);
    int mask = hashTableMask();
    if (minimumTableSize < mask) { // smaller table size will always be less than current mask

     */
    @Override
    public ImmutableBiMap<K, V> buildOrThrow() {
      if (size == 0) {
        return of();
      }
      if (valueComparator != null) {
        if (entriesUsed) {
          alternatingKeysAndValues = Arrays.copyOf(alternatingKeysAndValues, 2 * size);
        }
        sortEntries(alternatingKeysAndValues, size, valueComparator);
      }
      entriesUsed = true;

  @CanIgnoreReturnValue
  @CheckForNull
  MoveDesc<E> removeAt(int index) {
    checkPositionIndex(index, size);
    modCount++;
    size--;
    if (size == index) {
      queue[size] = null;
      return null;
    }
    E actualLastElement = elementData(size);
    int lastElementAt = heapForIndex(size).swapWithConceptuallyLastElement(actualLastElement);
    if (lastElementAt == index) {