@Override
  public int size() {
    return size;
  }

  @Override
  public boolean isEmpty() {
    return head == null;
  }

  @Override
  public boolean containsKey(@Nullable Object key) {
    return keyToKeyList.containsKey(key);
  }

  @Override
  public boolean containsValue(@Nullable Object value) {
    return values().contains(value);
  }

   *
   * @throws IllegalArgumentException if {@code node} is not an element of this network
   */
  int inDegree(N node);

  /**
   * Returns the count of {@code node}'s {@link #outEdges(Object) outgoing edges} in a directed
   * network. In an undirected network, returns the {@link #degree(Object)}.
   *

        a[k++] = items[i];
        i = inc(i);
      }
      return a;
    } finally {
      monitor.leave();
    }
  }

  /**
   * Returns an array containing all of the elements in this queue, in proper sequence; the runtime
   * type of the returned array is that of the specified array. If the queue fits in the specified
   * array, it is returned therein. Otherwise, a new array is allocated with the runtime type of the

      ImmutableMap<K, V> kvMap = (ImmutableMap<K, V>) map;
      if (!kvMap.isPartialView()) {
        return kvMap;
      }
    }
    return copyOf(map.entrySet());
  }

  /**
   * Returns an immutable map containing the specified entries. The returned map iterates over
   * entries in the same order as the original iterable.
   *

    @Override
    public boolean hasNext() {
      return !nextElements.isEmpty();
    }

    @Override
    public boolean hasPrevious() {
      return !previousElements.isEmpty();
    }

    @Override
    public E next() {
      return transferElement(nextElements, previousElements);
    }

    @Override
    public int nextIndex() {
      return previousElements.size();
    }

    @Override

   * @return {@code true} always
   */
  @CanIgnoreReturnValue
  @Override
  public boolean put(@ParametricNullness K key, @ParametricNullness V value) {
    return super.put(key, value);
  }

  /**
   * {@inheritDoc}
   *
   * <p>Though the method signature doesn't say so explicitly, the returned map has {@link List}
   * values.
   */
  @Override
  public Map<K, Collection<V>> asMap() {

  /**
   * @return a {@code ListenableFuture} representing pending completion of the task
   * @throws RejectedExecutionException {@inheritDoc}
   */
  @Override
  <T extends @Nullable Object> ListenableFuture<T> submit(
      Runnable task, @ParametricNullness T result);

  /**
   * {@inheritDoc}
   *
   * <p>All elements in the returned list must be {@link ListenableFuture} instances. The easiest

      if (!kvMultimap.isPartialView()) {
        return kvMultimap;
      }
    }

    return fromMapEntries(multimap.asMap().entrySet(), null);
  }

  /**
   * Returns an immutable multimap containing the specified entries. The returned multimap iterates
   * over keys in the order they were first encountered in the input, and the values for each key

      if (array[i] == target) {
        return i;
      }
    }
    return -1;
  }

  /**
   * Returns the values from each provided array combined into a single array. For example, {@code
   * concat(new boolean[] {a, b}, new boolean[] {}, new boolean[] {c}} returns the array {@code {a,
   * b, c}}.
   *
   * @param arrays zero or more {@code boolean} arrays

      if (array[i] == target) {
        return i;
      }
    }
    return -1;
  }

  /**
   * Returns the values from each provided array combined into a single array. For example, {@code
   * concat(new boolean[] {a, b}, new boolean[] {}, new boolean[] {c}} returns the array {@code {a,
   * b, c}}.
   *
   * @param arrays zero or more {@code boolean} arrays