RhodeCode

    Node source(Arc arc) const { return arc._id / _node_num; }

    Node target(Arc arc) const { return arc._id % _node_num; }

    static int id(Node node) { return node._id; }

    static int id(Arc arc) { return arc._id; }

    static Node nodeFromId(int id) { return Node(id);}

    static Arc arcFromId(int id) { return Arc(id);}

    typedef True FindArcTag;

    Arc findArc(Node s, Node t, Arc prev = INVALID) const {

    }

    class Node {

      friend class FullDigraphBase;

    protected:

      int _id;

      Node(int id) : _id(id) {}

    public:

      Node() {}

      Node (Invalid) : _id(-1) {}

      bool operator==(const Node node) const {return _id == node._id;}