*   <li>Nodes being visited multiple times (if multiple paths exist from any start node to any
   *       node reachable from any start node)
   * </ul>
   *
   * <p><b>Performance notes</b>
   *
   * <ul>
   *   <li>Traversals require <i>O(n)</i> time (where <i>n</i> is the number of nodes reachable from
   *       the start node).

   * EndpointPair [N2, N1] - skip
   * EndpointPair [N2, N3] - return
   * Visited Nodes = {N1, N2}
   * EndpointPair [N3, N1] - skip
   * EndpointPair [N3, N2] - skip
   * Visited Nodes = {N1, N2, N3}
   * EndpointPair [N4, N4] - return
   * Visited Nodes = {N1, N2, N3, N4}
   * </pre>
   */
  private static final class Undirected<N> extends EndpointPairIterator<N> {

    for (E key : keys) {
      LockGraphNode node = new LockGraphNode(getLockName(key));
      nodes.add(node);
      map.put(key, node);
    }
    // Pre-populate all allowedPriorLocks with nodes of smaller ordinal.
    for (int i = 1; i < numKeys; i++) {
      nodes.get(i).checkAcquiredLocks(Policies.THROW, nodes.subList(0, i));
    }
    // Pre-populate all disallowedPriorLocks with nodes of larger ordinal.

      return true;
    }
    if (!(obj instanceof Graph)) {
      return false;
    }
    Graph<?> other = (Graph<?>) obj;

    return isDirected() == other.isDirected()
        && nodes().equals(other.nodes())
        && edges().equals(other.edges());
  }

  @Override
  public final int hashCode() {
    return edges().hashCode();
  }

  /** Returns a string representation of this graph. */

## 0.49.2 (2020-02-29)

* Fix links in release notes. PR [#1052](https://github.com/tiangolo/fastapi/pull/1052) by [@sattosan](https://github.com/sattosan).
* Fix typo in release notes. PR [#1051](https://github.com/tiangolo/fastapi/pull/1051) by [@sattosan](https://github.com/sattosan).

    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()) {
      for (N successorNode : graph.successors(node)) {

    for (Integer node : graph.nodes()) {
      new EqualsTester()
          .addEqualityGroup(
              graph.predecessors(node), graph.successors(node), graph.adjacentNodes(node))
          .testEquals();
    }
  }

  @Override
  @Test
  public void nodes_checkReturnedSetMutability() {
    assume().that(graphIsMutable()).isTrue();

    Set<Integer> nodes = graph.nodes();

  int outDegree(N node);

  /**
   * Returns true if there is an edge that directly connects {@code nodeU} to {@code nodeV}. This is
   * equivalent to {@code nodes().contains(nodeU) && successors(nodeU).contains(nodeV)}.
   *
   * <p>In an undirected graph, this is equal to {@code hasEdgeConnecting(nodeV, nodeU)}.
   *
   * @since 23.0
   */
  @Override
  boolean hasEdgeConnecting(N nodeU, N nodeV);

  /**

        nodes.add(node);
    }

    /**
     * find a node by the GAV (metadata)
     *
     * @param md
     */
    public MetadataGraphNode findNode(MavenArtifactMetadata md) {
        for (MetadataGraphNode mgn : nodes) {
            if (mgn.metadata.equals(md)) {
                return mgn;
            }
        }

        MetadataGraphNode node = new MetadataGraphNode(md);
        addNode(node);

        assertThat(graph.degree(node)).isEqualTo(graph.adjacentNodes(node).size() + selfLoopCount);
        assertThat(graph.predecessors(node)).isEqualTo(graph.adjacentNodes(node));
        assertThat(graph.successors(node)).isEqualTo(graph.adjacentNodes(node));
        assertThat(graph.inDegree(node)).isEqualTo(graph.degree(node));
        assertThat(graph.outDegree(node)).isEqualTo(graph.degree(node));