}
  }

  /**
   * Returns a hash code, having the same bit length as each of the input hash codes, that combines
   * the information of these hash codes in an ordered fashion. That is, whenever two equal hash
   * codes are produced by two calls to this method, it is <i>as likely as possible</i> that each
   * was computed from the <i>same</i> input hash codes in the <i>same</i> order.
   *

     *
     * <p>This method is used when testing iterators without a known ordering. We poll the target
     * iterator's next element and pass it to the reference iterator through this method so it can
     * return the same element. This enables the assertion to pass and the reference iterator to
     * properly update its state.
     */
    void promoteToNext(E e) {
      if (nextElements.remove(e)) {
        nextElements.push(e);

    }
  }

  /**
   * Returns an immutable set multimap containing the same mappings as {@code multimap}. The
   * generated multimap's key and value orderings correspond to the iteration ordering of the {@code
   * multimap.asMap()} view. Repeated occurrences of an entry in the multimap after the first are
   * ignored.
   *
   * <p>Despite the method name, this method attempts to avoid actually copying the data when it is

    private final D genericDeclaration;
    private final String name;
    private final ImmutableList<Type> bounds;

    TypeVariableImpl(D genericDeclaration, String name, Type[] bounds) {
      disallowPrimitiveType(bounds, "bound for type variable");
      this.genericDeclaration = checkNotNull(genericDeclaration);
      this.name = checkNotNull(name);
      this.bounds = ImmutableList.copyOf(bounds);
    }

   * the members of the element set of {@code multiset2} that are not contained in {@code
   * multiset1}, with repeated occurrences of the same element appearing consecutively.
   *
   * <p>Results are undefined if {@code multiset1} and {@code multiset2} are based on different
   * equivalence relations (as {@code HashMultiset} and {@code TreeMultiset} are).
   *

        return new IllegalArgumentException(
            "Multiple entries with same key: " + key + "=" + value1 + " and " + key + "=" + value2);
      }
    }
  }

  /**
   * Returns an immutable map containing the same entries as {@code map}. The returned map iterates
   * over entries in the same order as the {@code entrySet} of the original map. If {@code map}

     *
     * <p>This method is used when testing iterators without a known ordering. We poll the target
     * iterator's next element and pass it to the reference iterator through this method so it can
     * return the same element. This enables the assertion to pass and the reference iterator to
     * properly update its state.
     */
    void promoteToNext(E e) {
      if (nextElements.remove(e)) {
        nextElements.push(e);

        return next;
      }
    }
    return null;
  }

  /**
   * Determines whether two iterables contain equal elements in the same order. More specifically,
   * this method returns {@code true} if {@code iterable1} and {@code iterable2} contain the same
   * number of elements and every element of {@code iterable1} is equal to the corresponding element
   * of {@code iterable2}.
   */

   * safe to do so. The exact circumstances under which a copy will or will not be performed are
   * undocumented and subject to change.
   *
   * @throws IllegalArgumentException if two keys have the same value or two values have the same
   *     key
   * @throws NullPointerException if any key or value in {@code map} is null
   */

 * Ordering#leastOf(Iterable, int)}, which provides the same implementation with an interface
 * tailored to that use case.
 *
 * <p>This uses the same efficient implementation as {@link Ordering#leastOf(Iterable, int)},
 * offering expected O(n + k log k) performance (worst case O(n log k)) for n calls to {@link
 * #offer} and a call to {@link #topK}, with O(k) memory. In comparison, quickselect has the same