private static <NodeType extends IGraphNode<NodeType>> void link(
      final NodeType parent,
      final NodeType node,
      final HashMap<NodeType, NodeType> ancestor,
      final HashMap<NodeType, NodeType> best) {
    ancestor.put(node, parent);
    best.put(node, node);
  }
Add edge p -> n to spanning forest implied by ancestor array.

@param <NodeType> Type of the nodes in the directed graph.
java/zylib/src/main/java/com/google/security/zynamics/zylib/types/graphs/algorithms/LengauerTarjan.java