public SortedMultiset<E> subMultiset(
      E fromElement, BoundType fromBoundType, E toElement, BoundType toBoundType) {
    return forwardMultiset()
        .subMultiset(toElement, toBoundType, fromElement, fromBoundType)
        .descendingMultiset();
  }

  @Override
  public SortedMultiset<E> tailMultiset(E fromElement, BoundType boundType) {
    return forwardMultiset().headMultiset(fromElement, boundType).descendingMultiset();
  }

  }

  @Override
  ImmutableSortedSet<E> subSetImpl(
      E fromElement, boolean fromInclusive, E toElement, boolean toInclusive) {
    return forward.subSet(toElement, toInclusive, fromElement, fromInclusive).descendingSet();
  }

  @Override
  ImmutableSortedSet<E> tailSetImpl(E fromElement, boolean inclusive) {
    return forward.headSet(fromElement, inclusive).descendingSet();
  }

  @Override

      @ParametricNullness E fromElement,
      BoundType fromBoundType,
      @ParametricNullness E toElement,
      BoundType toBoundType) {
    return forwardMultiset()
        .subMultiset(toElement, toBoundType, fromElement, fromBoundType)
        .descendingMultiset();
  }

  @Override
  public SortedMultiset<E> tailMultiset(@ParametricNullness E fromElement, BoundType boundType) {

  ImmutableSortedSet<E> subSetImpl(
      E fromElement, boolean fromInclusive, E toElement, boolean toInclusive) {
    return tailSetImpl(fromElement, fromInclusive).headSetImpl(toElement, toInclusive);
  }

  @Override
  ImmutableSortedSet<E> tailSetImpl(E fromElement, boolean inclusive) {
    return getSubSet(tailIndex(fromElement, inclusive), size());
  }

  int tailIndex(E fromElement, boolean inclusive) {

      @ParametricNullness E fromElement,
      BoundType fromBoundType,
      @ParametricNullness E toElement,
      BoundType toBoundType) {
    return forwardMultiset()
        .subMultiset(toElement, toBoundType, fromElement, fromBoundType)
        .descendingMultiset();
  }

  @Override
  public SortedMultiset<E> tailMultiset(@ParametricNullness E fromElement, BoundType boundType) {

  ContiguousSet<C> subSetImpl(
      C fromElement, boolean fromInclusive, C toElement, boolean toInclusive) {
    if (fromElement.compareTo(toElement) == 0 && !fromInclusive && !toInclusive) {
      // Range would reject our attempt to create (x, x).
      return new EmptyContiguousSet<>(domain);
    }
    return intersectionInCurrentDomain(
        Range.range(
            fromElement, BoundType.forBoolean(fromInclusive),

  }

  @Override
  ImmutableSortedSet<E> subSetImpl(
      E fromElement, boolean fromInclusive, E toElement, boolean toInclusive) {
    return forward.subSet(toElement, toInclusive, fromElement, fromInclusive).descendingSet();
  }

  @Override
  ImmutableSortedSet<E> tailSetImpl(E fromElement, boolean inclusive) {
    return forward.headSet(fromElement, inclusive).descendingSet();
  }

  @Override

   * keeps the original {@code fromElement}.
   */
  @Override
  public ImmutableSortedSet<E> tailSet(E fromElement) {
    return tailSet(fromElement, true);
  }

  /**
   * @since 12.0
   */
  @Override
  public ImmutableSortedSet<E> tailSet(E fromElement, boolean inclusive) {
    return tailSetImpl(checkNotNull(fromElement), inclusive);
  }

  /*

          sortedMap().subMap(fromElement, fromInclusive, toElement, toInclusive));
    }

    @Override
    public NavigableSet<K> tailSet(@ParametricNullness K fromElement) {
      return tailSet(fromElement, true);
    }

    @Override
    public NavigableSet<K> tailSet(@ParametricNullness K fromElement, boolean inclusive) {
      return new NavigableKeySet(sortedMap().tailMap(fromElement, inclusive));
    }
  }

  ContiguousSet<C> subSetImpl(
      C fromElement, boolean fromInclusive, C toElement, boolean toInclusive) {
    if (fromElement.compareTo(toElement) == 0 && !fromInclusive && !toInclusive) {
      // Range would reject our attempt to create (x, x).
      return new EmptyContiguousSet<>(domain);
    }
    return intersectionInCurrentDomain(
        Range.range(
            fromElement, BoundType.forBoolean(fromInclusive),