XmlNode node1 = (XmlNode) pointer1.getBaseValue();
        XmlNode node2 = (XmlNode) pointer2.getBaseValue();
        if (node1 == node2) {
            return 0;
        }
        for (XmlNode child : node.children()) {
            if (child == node1) {
                return -1;
            }
            if (child == node2) {
                return 1;
            }
        }

     */

    @Override
    public ResolutionNode resolveConflict(ResolutionNode node1, ResolutionNode node2) {
        try {
            ArtifactVersion version1 = node1.getArtifact().getSelectedVersion();
            ArtifactVersion version2 = node2.getArtifact().getSelectedVersion();

            return version1.compareTo(version2) <= 0 ? node1 : node2;
        } catch (OverConstrainedVersionException exception) {

     *      org.apache.maven.artifact.resolver.ResolutionNode)
     */

    @Override
    public ResolutionNode resolveConflict(ResolutionNode node1, ResolutionNode node2) {
        return node1.getDepth() <= node2.getDepth() ? node1 : node2;
    }

        add.forEach((name, node) -> org.merge(name, node, this::merge));
        return org;
    }

    private BuildStep merge(BuildStep node1, BuildStep node2) {
        node1.predecessors.addAll(node2.predecessors);
        node1.successors.addAll(node2.successors);
        node2.mojos.forEach((k, v) -> node1.mojos.merge(k, v, this::mergeMojos));
        return node1;
    }

     *      org.apache.maven.artifact.resolver.ResolutionNode)
     */

    @Override
    public ResolutionNode resolveConflict(ResolutionNode node1, ResolutionNode node2) {
        return node1.getDepth() >= node2.getDepth() ? node1 : node2;
    }

     */

    @Override
    public ResolutionNode resolveConflict(ResolutionNode node1, ResolutionNode node2) {
        try {
            ArtifactVersion version1 = node1.getArtifact().getSelectedVersion();
            ArtifactVersion version2 = node2.getArtifact().getSelectedVersion();

            return version1.compareTo(version2) > 0 ? node1 : node2;
        } catch (OverConstrainedVersionException exception) {

    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.

    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.

      checkArgument(
          edge.length() == 2, "Expecting each edge to consist of 2 characters but got %s", edge);
      char node1 = edge.charAt(0);
      char node2 = edge.charAt(1);
      graphMapBuilder.put(node1, node2);
      if (!directed) {
        graphMapBuilder.put(node2, node1);
      }
    }
    ImmutableMultimap<Character, Character> graphMap = graphMapBuilder.build();

  TF_Operation *node1, *node2, *node3;
  NodeWithPlaceholderAttrHelper(func_graph.get(), s.get(), "node1", "v1",
                                &node1);
  NodeWithPlaceholderAttrHelper(func_graph.get(), s.get(), "node2", "v1",
                                &node2);
  NodeWithPlaceholderAttrHelper(func_graph.get(), s.get(), "node3", "v2",
                                &node3);