RhodeCode

      nodes.push_back(NodeT());

      nodes[n].first_out = -1;

      return Node(n);

    }

      int n = arcs.size();

      arcs.push_back(ArcT());

      arcs.push_back(ArcT());

      arcs[n].target = u._id;

      arcs[n | 1].target = v._id;

    ///Add a new edge to the graph.

    ///Add a new edge to the graph with node \c s

    ///and \c t.

    ///\return the new edge.

    Edge addEdge(const Node& s, const Node& t) { 

    }

    ///Clear the graph.

    ///Erase all the nodes and edges from the graph.

    ///