private static final AbstractGraphBuilder<?> GRAPH_BUILDER_A =
      GraphBuilder.directed().expectedNodeCount(10);
  private static final AbstractGraphBuilder<?> GRAPH_BUILDER_B =
      ValueGraphBuilder.directed().allowsSelfLoops(true).expectedNodeCount(16);

  private static final ImmutableGraph<String> IMMUTABLE_GRAPH_A =
      GraphBuilder.directed().<String>immutable().addNode("A").build();

  /**
   * Specifies the expected number of nodes in the network.
   *
   * @throws IllegalArgumentException if {@code expectedNodeCount} is negative
   */
  @CanIgnoreReturnValue
  public NetworkBuilder<N, E> expectedNodeCount(int expectedNodeCount) {
    this.expectedNodeCount = Optional.of(checkNonNegative(expectedNodeCount));
    return this;
  }

  /**
   * Specifies the expected number of edges in the network.
   *

  /**
   * Specifies the expected number of nodes in the graph.
   *
   * @throws IllegalArgumentException if {@code expectedNodeCount} is negative
   */
  @CanIgnoreReturnValue
  public ValueGraphBuilder<N, V> expectedNodeCount(int expectedNodeCount) {
    this.expectedNodeCount = Optional.of(checkNonNegative(expectedNodeCount));
    return this;
  }

  /**

  /**
   * Specifies the expected number of nodes in the graph.
   *
   * @throws IllegalArgumentException if {@code expectedNodeCount} is negative
   */
  @CanIgnoreReturnValue
  public GraphBuilder<N> expectedNodeCount(int expectedNodeCount) {
    this.expectedNodeCount = Optional.of(checkNonNegative(expectedNodeCount));
    return this;
  }

  /**
   * Specifies the order of iteration for the elements of {@link Graph#nodes()}.

  private static final AbstractGraphBuilder<?> GRAPH_BUILDER_A =
      GraphBuilder.directed().expectedNodeCount(10);
  private static final AbstractGraphBuilder<?> GRAPH_BUILDER_B =
      ValueGraphBuilder.directed().allowsSelfLoops(true).expectedNodeCount(16);

  private static final ImmutableGraph<String> IMMUTABLE_GRAPH_A =
      GraphBuilder.directed().<String>immutable().addNode("A").build();

    assertThat(undirectedMultigraph.edgesConnecting(N1, N2))
        .isEqualTo(ImmutableSet.of(E12, E12_A, E21));
  }

  @Test
  public void createDirected_expectedNodeCount() {
    MutableNetwork<Integer, String> directedGraph =
        NetworkBuilder.directed().expectedNodeCount(NODE_COUNT).build();
    assertThat(directedGraph.addEdge(N1, N2, E12)).isTrue();
    assertThat(directedGraph.edgesConnecting(N1, N2)).isEqualTo(ImmutableSet.of(E12));

    assertThat(undirectedMultigraph.edgesConnecting(N1, N2))
        .isEqualTo(ImmutableSet.of(E12, E12_A, E21));
  }

  @Test
  public void createDirected_expectedNodeCount() {
    MutableNetwork<Integer, String> directedGraph =
        NetworkBuilder.directed().expectedNodeCount(NODE_COUNT).build();
    assertThat(directedGraph.addEdge(N1, N2, E12)).isTrue();
    assertThat(directedGraph.edgesConnecting(N1, N2)).isEqualTo(ImmutableSet.of(E12));

   */
  public static <N> MutableGraph<N> inducedSubgraph(Graph<N> graph, Iterable<? extends N> nodes) {
    MutableGraph<N> subgraph =
        (nodes instanceof Collection)
            ? GraphBuilder.from(graph).expectedNodeCount(((Collection) nodes).size()).build()
            : GraphBuilder.from(graph).build();
    for (N node : nodes) {
      subgraph.addNode(node);
    }
    for (N node : subgraph.nodes()) {

  final boolean directed;
  boolean allowsSelfLoops = false;
  ElementOrder<N> nodeOrder = ElementOrder.insertion();
  ElementOrder<N> incidentEdgeOrder = ElementOrder.unordered();

  Optional<Integer> expectedNodeCount = Optional.absent();

  /**
   * Creates a new instance with the specified edge directionality.
   *
   * @param directed if true, creates an instance for graphs whose edges are each directed; if

  StandardValueGraph(AbstractGraphBuilder<? super N> builder) {
    this(
        builder,
        builder.nodeOrder.<N, GraphConnections<N, V>>createMap(
            builder.expectedNodeCount.or(DEFAULT_NODE_COUNT)),
        0L);
  }

  /**
   * Constructs a graph with the properties specified in {@code builder}, initialized with the given
   * node map.
   */
  StandardValueGraph(