return result;
  }

  /*
   * For discussion of the safety of the following methods for operating on predecessors and
   * successors, see the comments near the end of CompactHashMap, noting that the methods here call
   * link(), which is defined at the end of this file.
   */

  private int getPredecessor(int entry) {
    return ((int) (link(entry) >>> 32)) - 1;
  }

  @Override
  int getSuccessor(int entry) {

  private static String badPositionIndexes(int start, int end, int size) {
    if (start < 0 || start > size) {
      return badPositionIndex(start, size, "start index");
    }
    if (end < 0 || end > size) {
      return badPositionIndex(end, size, "end index");
    }
    // end < start
    return lenientFormat("end index (%s) must not be less than start index (%s)", end, start);
  }

    final float[] array;
    final int start;
    final int end;

    FloatArrayAsList(float[] array) {
      this(array, 0, array.length);
    }

    FloatArrayAsList(float[] array, int start, int end) {
      this.array = array;
      this.start = start;
      this.end = end;
    }

    @Override
    public int size() {
      return end - start;
    }

    @Override

    final double[] array;
    final int start;
    final int end;

    DoubleArrayAsList(double[] array) {
      this(array, 0, array.length);
    }

    DoubleArrayAsList(double[] array, int start, int end) {
      this.array = array;
      this.start = start;
      this.end = end;
    }

    @Override
    public int size() {
      return end - start;
    }

    @Override

  private Comparators() {}

  /**
   * Returns a new comparator which sorts iterables by comparing corresponding elements pairwise
   * until a nonzero result is found; imposes "dictionary order." If the end of one iterable is
   * reached, but not the other, the shorter iterable is considered to be less than the longer one.
   * For example, a lexicographical natural ordering over integers considers {@code [] < [1] < [1,

      if (!executed) {
        runnables = new RunnableExecutorPair(runnable, executor, runnables);
        return;
      }
    }
    // Execute the runnable immediately. Because of scheduling this may end up getting called before
    // some of the previously added runnables, but we're OK with that. If we want to change the
    // contract to guarantee ordering among runnables we'd have to modify the logic here to allow
    // it.

    mmHeap.addAll(Lists.newArrayList(1, 2));
    Iterator<Integer> it = mmHeap.iterator();
    assertTrue("Iterator has reached end prematurely", it.hasNext());
    it.next();
    it.next();
    try {
      it.next();
      fail("No exception thrown when iterating past end of heap");
    } catch (NoSuchElementException expected) {
    }
  }

  public void testIteratorConcurrentModification() {

    assertEquals("3", iterator.next());
    assertEquals("4", iterator.next());
    assertEquals(4, iterator.nextIndex());
    try {
      iterator.next();
      fail("did not detect end of list");
    } catch (NoSuchElementException expected) {
    }
    assertEquals(3, iterator.previousIndex());
    assertEquals("4", iterator.previous());
    assertEquals("3", iterator.previous());

    // * Everything with (to <= index < from) should be removed.
    // * The element with (index == from) should be kept.
    // * Everything with (index > from) has not been checked yet.

    // Check from the end of the list backwards (minimize expected cost of
    // moving elements when remove() is called). Stop before 'from' because
    // we already know that should be kept.
    for (int n = list.size() - 1; n > from; n--) {

    } catch (NoSuchElementException e) {
      /* expected */
    }
    try {
      peekingIterator.next();
      fail("next() should still throw exception after the end of iteration");
    } catch (NoSuchElementException e) {
      /* expected */
    }
  }

  public void testCantRemoveAfterPeek() {
    List<String> list = Lists.newArrayList("A", "B", "C");