if (index1 >= 0) {
                    index = index1;
                }
            }

            if (index < 0) {
                throw new InvalidVersionSpecificationException("Unbounded range: " + spec);
            }

            Restriction restriction = parseRestriction(process.substring(0, index + 1));
            if (lowerBound == null) {
                lowerBound = restriction.getLowerBound();

 * its greatest element, as determined by the queue's specified comparator. If no comparator is
 * given at creation time, the natural order of elements is used. If no maximum size is given at
 * creation time, the queue is unbounded.
 *
 * <p>Usage example:
 *
 * <pre>{@code
 * MinMaxPriorityQueue<User> users = MinMaxPriorityQueue.orderedBy(userComparator)
 *     .maximumSize(1000)
 *     .create();
 * }</pre>
 *

 * its greatest element, as determined by the queue's specified comparator. If no comparator is
 * given at creation time, the natural order of elements is used. If no maximum size is given at
 * creation time, the queue is unbounded.
 *
 * <p>Usage example:
 *
 * <pre>{@code
 * MinMaxPriorityQueue<User> users = MinMaxPriorityQueue.orderedBy(userComparator)
 *     .maximumSize(1000)
 *     .create();
 * }</pre>
 *

  private final class ComplementRanges extends ImmutableList<Range<C>> {
    // True if the "positive" range set is empty or bounded below.
    private final boolean positiveBoundedBelow;

    // True if the "positive" range set is empty or bounded above.
    private final boolean positiveBoundedAbove;

    private final int size;

    ComplementRanges() {