RhodeCode

/* -*- mode: C++; indent-tabs-mode: nil; -*-

 *

 * This file is a part of LEMON, a generic C++ optimization library.

 *

 * Copyright (C) 2003-2009

 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

 * (Egervary Research Group on Combinatorial Optimization, EGRES).

 *

 * Permission to use, modify and distribute this software is granted

 * provided that this copyright notice appears in all copies. For

 * precise terms see the accompanying LICENSE file.

 *

 * This software is provided "AS IS" with no warranty of any kind,

 * express or implied, and with no claim as to its suitability for any

 * purpose.

 *

 */

#ifndef LEMON_BITS_GRAPH_ADAPTOR_EXTENDER_H

#define LEMON_BITS_GRAPH_ADAPTOR_EXTENDER_H

#include <lemon/core.h>

#include <lemon/error.h>

namespace lemon {

  template <typename _Digraph>

  class DigraphAdaptorExtender : public _Digraph {

  public:

    typedef _Digraph Parent;

    typedef _Digraph Digraph;

    typedef DigraphAdaptorExtender Adaptor;

    // Base extensions

    typedef typename Parent::Node Node;

    typedef typename Parent::Arc Arc;

    int maxId(Node) const {

      return Parent::maxNodeId();

    }

    int maxId(Arc) const {

      return Parent::maxArcId();

    }

    Node fromId(int id, Node) const {

      return Parent::nodeFromId(id);

    }

    Arc fromId(int id, Arc) const {

      return Parent::arcFromId(id);

    }

    Node oppositeNode(const Node &n, const Arc &e) const {

      if (n == Parent::source(e))

        return Parent::target(e);

      else if(n==Parent::target(e))

        return Parent::source(e);

      else

        return INVALID;

    }

    class NodeIt : public Node {

      const Adaptor* _adaptor;

    public:

      NodeIt() {}

      NodeIt(Invalid i) : Node(i) { }

      explicit NodeIt(const Adaptor& adaptor) : _adaptor(&adaptor) {

        _adaptor->first(static_cast<Node&>(*this));

      }

      NodeIt(const Adaptor& adaptor, const Node& node)

        : Node(node), _adaptor(&adaptor) {}

      NodeIt& operator++() {

        _adaptor->next(*this);

        return *this;

      }

    };

    class ArcIt : public Arc {

      const Adaptor* _adaptor;

    public:

      ArcIt() { }

      ArcIt(Invalid i) : Arc(i) { }

      explicit ArcIt(const Adaptor& adaptor) : _adaptor(&adaptor) {

        _adaptor->first(static_cast<Arc&>(*this));

      }

      ArcIt(const Adaptor& adaptor, const Arc& e) :

        Arc(e), _adaptor(&adaptor) { }

      ArcIt& operator++() {

        _adaptor->next(*this);

        return *this;

      }

    };

    class OutArcIt : public Arc {

      const Adaptor* _adaptor;

    public:

      OutArcIt() { }

      OutArcIt(Invalid i) : Arc(i) { }

      OutArcIt(const Adaptor& adaptor, const Node& node)

        : _adaptor(&adaptor) {

        _adaptor->firstOut(*this, node);

      }

      OutArcIt(const Adaptor& adaptor, const Arc& arc)

        : Arc(arc), _adaptor(&adaptor) {}

      OutArcIt& operator++() {

        _adaptor->nextOut(*this);

        return *this;

      }

    };

    class InArcIt : public Arc {

      const Adaptor* _adaptor;

    public:

      InArcIt() { }

      InArcIt(Invalid i) : Arc(i) { }

      InArcIt(const Adaptor& adaptor, const Node& node)

        : _adaptor(&adaptor) {

        _adaptor->firstIn(*this, node);

      }

      InArcIt(const Adaptor& adaptor, const Arc& arc) :

        Arc(arc), _adaptor(&adaptor) {}

      InArcIt& operator++() {

        _adaptor->nextIn(*this);

/* -*- mode: C++; indent-tabs-mode: nil; -*-

 *

 * This file is a part of LEMON, a generic C++ optimization library.

 *

 * Copyright (C) 2003-2009

 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

 * (Egervary Research Group on Combinatorial Optimization, EGRES).

 *

 * Permission to use, modify and distribute this software is granted

 * provided that this copyright notice appears in all copies. For

 * precise terms see the accompanying LICENSE file.

 *

 * This software is provided "AS IS" with no warranty of any kind,

 * express or implied, and with no claim as to its suitability for any

 * purpose.

 *

 */

#ifndef LEMON_BITS_MAP_EXTENDER_H

#define LEMON_BITS_MAP_EXTENDER_H

#include <iterator>

#include <lemon/bits/traits.h>

#include <lemon/concept_check.h>

#include <lemon/concepts/maps.h>

//\file

//\brief Extenders for iterable maps.

namespace lemon {

  // \ingroup graphbits

  //

  // \brief Extender for maps

  template <typename _Map>

  class MapExtender : public _Map {

  public:

    typedef _Map Parent;

    typedef MapExtender Map;

    typedef typename Parent::Graph Graph;

    typedef typename Parent::Key Item;

    typedef typename Parent::Key Key;

    typedef typename Parent::Value Value;

    class MapIt;

    class ConstMapIt;

    friend class MapIt;

    friend class ConstMapIt;

  public:

    MapExtender(const Graph& graph)

      : Parent(graph) {}

    MapExtender(const Graph& graph, const Value& value)

      : Parent(graph, value) {}

  private:

    MapExtender& operator=(const MapExtender& cmap) {

      return operator=<MapExtender>(cmap);

    }

    template <typename CMap>

    MapExtender& operator=(const CMap& cmap) {

      Parent::operator=(cmap);

      return *this;

    }

  public:

    class MapIt : public Item {

    public:

      typedef Item Parent;

      typedef typename Map::Value Value;

      MapIt() {}

      MapIt(Invalid i) : Parent(i) { }

      explicit MapIt(Map& _map) : map(_map) {

        map.notifier()->first(*this);

      }

      MapIt(const Map& _map, const Item& item)

        : Parent(item), map(_map) {}

      MapIt& operator++() {

        map.notifier()->next(*this);

        return *this;

      }

      typename MapTraits<Map>::ConstReturnValue operator*() const {

        return map[*this];

      }

      typename MapTraits<Map>::ReturnValue operator*() {

        return map[*this];

      }

      void set(const Value& value) {

        map.set(*this, value);

      }

    protected:

      Map& map;

    };

    class ConstMapIt : public Item {

    public:

      typedef Item Parent;

      typedef typename Map::Value Value;

      ConstMapIt() {}

      ConstMapIt(Invalid i) : Parent(i) { }

      explicit ConstMapIt(Map& _map) : map(_map) {

        map.notifier()->first(*this);

      }

      ConstMapIt(const Map& _map, const Item& item)

        : Parent(item), map(_map) {}

      ConstMapIt& operator++() {

        map.notifier()->next(*this);

        return *this;

      }

      typename MapTraits<Map>::ConstReturnValue operator*() const {

        return map[*this];

      }

    protected:

      const Map& map;

    };

    class ItemIt : public Item {

    public:

      typedef Item Parent;

      ItemIt() {}

      ItemIt(Invalid i) : Parent(i) { }

      explicit ItemIt(Map& _map) : map(_map) {

        map.notifier()->first(*this);

      }

      ItemIt(const Map& _map, const Item& item)

        : Parent(item), map(_map) {}

      ItemIt& operator++() {

        map.notifier()->next(*this);

        return *this;

      }

    protected:

      const Map& map;

    };

  };

  // \ingroup graphbits

  //

  // \brief Extender for maps which use a subset of the items.

  template <typename _Graph, typename _Map>

  class SubMapExtender : public _Map {

  public:

    typedef _Map Parent;

    typedef SubMapExtender Map;

    typedef _Graph Graph;

    typedef typename Parent::Key Item;

    typedef typename Parent::Key Key;

    typedef typename Parent::Value Value;

    class MapIt;

    class ConstMapIt;

    friend class MapIt;

    friend class ConstMapIt;

  public:

    SubMapExtender(const Graph& _graph)

      : Parent(_graph), graph(_graph) {}

    SubMapExtender(const Graph& _graph, const Value& _value)

      : Parent(_graph, _value), graph(_graph) {}

  private:

    SubMapExtender& operator=(const SubMapExtender& cmap) {

      return operator=<MapExtender>(cmap);

    }

    template <typename CMap>

    SubMapExtender& operator=(const CMap& cmap) {

      checkConcept<concepts::ReadMap<Key, Value>, CMap>();

      Item it;

      for (graph.first(it); it != INVALID; graph.next(it)) {

        Parent::set(it, cmap[it]);

      }

      return *this;

    }

  public:

    class MapIt : public Item {

    public:

      typedef Item Parent;

      typedef typename Map::Value Value;

      MapIt() {}

      MapIt(Invalid i) : Parent(i) { }

      explicit MapIt(Map& _map) : map(_map) {

        map.graph.first(*this);

      }

      MapIt(const Map& _map, const Item& item)

        : Parent(item), map(_map) {}

      MapIt& operator++() {

        map.graph.next(*this);

        return *this;

      }

      typename MapTraits<Map>::ConstReturnValue operator*() const {

        return map[*this];

      }

      typename MapTraits<Map>::ReturnValue operator*() {

        return map[*this];

      }

      void set(const Value& value) {

        map.set(*this, value);

      }

    protected:

      Map& map;

    };

    class ConstMapIt : public Item {

    public:

      typedef Item Parent;

      typedef typename Map::Value Value;

      ConstMapIt() {}

      ConstMapIt(Invalid i) : Parent(i) { }

      explicit ConstMapIt(Map& _map) : map(_map) {

        map.graph.first(*this);

      }

      ConstMapIt(const Map& _map, const Item& item)

        : Parent(item), map(_map) {}

      ConstMapIt& operator++() {

        map.graph.next(*this);

        return *this;

      }

      typename MapTraits<Map>::ConstReturnValue operator*() const {

        return map[*this];

      }

    protected:

      const Map& map;

    };

    class ItemIt : public Item {

    public:

      typedef Item Parent;

      ItemIt() {}

      ItemIt(Invalid i) : Parent(i) { }

      explicit ItemIt(Map& _map) : map(_map) {

        map.graph.first(*this);

      }

      ItemIt(const Map& _map, const Item& item)

        : Parent(item), map(_map) {}

      ItemIt& operator++() {

        map.graph.next(*this);

        return *this;

      }

    protected:

      const Map& map;

    };

  private:

      };

      /// This iterator goes through each arc.

      /// This iterator goes through each arc of a digraph.

      /// Its usage is quite simple, for example you can count the number

      /// of arcs in a digraph \c g of type \c Digraph as follows:

      ///\code

      /// int count=0;

      /// for(Digraph::ArcIt e(g); e!=INVALID; ++e) ++count;

      ///\endcode

      class ArcIt : public Arc {

      public:

        /// Default constructor

        /// @warning The default constructor sets the iterator

        /// to an undefined value.

        ArcIt() { }

        /// Copy constructor.

        /// Copy constructor.

        ///

        ArcIt(const ArcIt& e) : Arc(e) { }

        /// Initialize the iterator to be invalid.

        /// Initialize the iterator to be invalid.

        ///

        ArcIt(Invalid) { }

        /// This constructor sets the iterator to the first arc.

        /// This constructor sets the iterator to the first arc of \c g.

        ///@param g the digraph

        ArcIt(const Digraph& g) { ignore_unused_variable_warning(g); }

        /// Arc -> ArcIt conversion

        /// Sets the iterator to the value of the trivial iterator \c e.

        /// This feature necessitates that each time we

        /// iterate the arc-set, the iteration order is the same.

        ArcIt(const Digraph&, const Arc&) { }

        ///Next arc

        /// Assign the iterator to the next arc.

        ArcIt& operator++() { return *this; }

      };

      ///Gives back the target node of an arc.

      ///Gives back the target node of an arc.

      ///

      Node target(Arc) const { return INVALID; }

      ///Gives back the source node of an arc.

      ///Gives back the source node of an arc.

      ///

      Node source(Arc) const { return INVALID; }

      /// \brief Returns the ID of the node.

      int id(Node) const { return -1; }

      /// \brief Returns the ID of the arc.

      int id(Arc) const { return -1; }

      /// \brief Returns the node with the given ID.

      ///

      /// \pre The argument should be a valid node ID in the graph.

      Node nodeFromId(int) const { return INVALID; }

      /// \brief Returns the arc with the given ID.

      ///

      /// \pre The argument should be a valid arc ID in the graph.

      Arc arcFromId(int) const { return INVALID; }

      /// \brief Returns an upper bound on the node IDs.

      int maxNodeId() const { return -1; }

      /// \brief Returns an upper bound on the arc IDs.

      int maxArcId() const { return -1; }

      void first(Node&) const {}

      void next(Node&) const {}

      void first(Arc&) const {}

      void next(Arc&) const {}

      void firstIn(Arc&, const Node&) const {}

      void nextIn(Arc&) const {}

      void firstOut(Arc&, const Node&) const {}

      void nextOut(Arc&) const {}

      // The second parameter is dummy.

      Node fromId(int, Node) const { return INVALID; }

      // The second parameter is dummy.

      Arc fromId(int, Arc) const { return INVALID; }

      // Dummy parameter.

      int maxId(Node) const { return -1; }

      // Dummy parameter.

      int maxId(Arc) const { return -1; }

      /// \brief The base node of the iterator.

      ///

      /// Gives back the base node of the iterator.

      /// It is always the target of the pointed arc.

      Node baseNode(const InArcIt&) const { return INVALID; }

      /// \brief The running node of the iterator.

      ///

      /// Gives back the running node of the iterator.

      /// It is always the source of the pointed arc.

      Node runningNode(const InArcIt&) const { return INVALID; }

      /// \brief The base node of the iterator.

      ///

      /// Gives back the base node of the iterator.

      /// It is always the source of the pointed arc.

      Node baseNode(const OutArcIt&) const { return INVALID; }

      /// \brief The running node of the iterator.

      ///

      /// Gives back the running node of the iterator.

      /// It is always the target of the pointed arc.

      Node runningNode(const OutArcIt&) const { return INVALID; }

      /// \brief The opposite node on the given arc.

      ///

      /// Gives back the opposite node on the given arc.

      Node oppositeNode(const Node&, const Arc&) const { return INVALID; }

      ///

      template<class T>

      public:

        ///\e

        NodeMap(const Digraph&) { }

        ///\e

        NodeMap(const Digraph&, T) { }

      private:

        ///Copy constructor

        ///Assignment operator

        template <typename CMap>

        NodeMap& operator=(const CMap&) {

          checkConcept<ReadMap<Node, T>, CMap>();

          return *this;

        }

      };

      ///

      /// Reference map of the arcs to type \c T.

      template<class T>

      public:

        ///\e

        ArcMap(const Digraph&) { }

        ///\e

        ArcMap(const Digraph&, T) { }

      private:

        ///Copy constructor

        ///Assignment operator

        template <typename CMap>

        ArcMap& operator=(const CMap&) {

          checkConcept<ReadMap<Arc, T>, CMap>();

          return *this;

        }

      };

      template <typename _Digraph>

      struct Constraints {

        void constraints() {

          checkConcept<IterableDigraphComponent<>, _Digraph>();

          checkConcept<IDableDigraphComponent<>, _Digraph>();

          checkConcept<MappableDigraphComponent<>, _Digraph>();

        }

      };

    };

  } //namespace concepts

} //namespace lemon

#endif

        ///

        ArcIt(const ArcIt& e) : Arc(e) { }

        /// Initialize the iterator to be invalid.

        /// Initialize the iterator to be invalid.

        ///

        ArcIt(Invalid) { }

        /// This constructor sets the iterator to the first arc.

        /// This constructor sets the iterator to the first arc of \c g.

        ///@param g the graph

        ArcIt(const Graph &g) { ignore_unused_variable_warning(g); }

        /// Arc -> ArcIt conversion

        /// Sets the iterator to the value of the trivial iterator \c e.

        /// This feature necessitates that each time we

        /// iterate the arc-set, the iteration order is the same.

        ArcIt(const Graph&, const Arc&) { }

        ///Next arc

        /// Assign the iterator to the next arc.

        ArcIt& operator++() { return *this; }

      };

      /// This iterator goes trough the outgoing directed arcs of a node.

      /// This iterator goes trough the \e outgoing arcs of a certain node

      /// of a graph.

      /// Its usage is quite simple, for example you can count the number

      /// of outgoing arcs of a node \c n

      /// in graph \c g of type \c Graph as follows.

      ///\code

      /// int count=0;

      /// for (Graph::OutArcIt e(g, n); e!=INVALID; ++e) ++count;

      ///\endcode

      class OutArcIt : public Arc {

      public:

        /// Default constructor

        /// @warning The default constructor sets the iterator

        /// to an undefined value.

        OutArcIt() { }

        /// Copy constructor.

        /// Copy constructor.

        ///

        OutArcIt(const OutArcIt& e) : Arc(e) { }

        /// Initialize the iterator to be invalid.

        /// Initialize the iterator to be invalid.

        ///

        OutArcIt(Invalid) { }

        /// This constructor sets the iterator to the first outgoing arc.

        /// This constructor sets the iterator to the first outgoing arc of

        /// the node.

        ///@param n the node

        ///@param g the graph

        OutArcIt(const Graph& n, const Node& g) {

          ignore_unused_variable_warning(n);

          ignore_unused_variable_warning(g);

        }

        /// Arc -> OutArcIt conversion

        /// Sets the iterator to the value of the trivial iterator.

        /// This feature necessitates that each time we

        /// iterate the arc-set, the iteration order is the same.

        OutArcIt(const Graph&, const Arc&) { }

        ///Next outgoing arc

        /// Assign the iterator to the next

        /// outgoing arc of the corresponding node.

        OutArcIt& operator++() { return *this; }

      };

      /// This iterator goes trough the incoming directed arcs of a node.

      /// This iterator goes trough the \e incoming arcs of a certain node

      /// of a graph.

      /// Its usage is quite simple, for example you can count the number

      /// of outgoing arcs of a node \c n

      /// in graph \c g of type \c Graph as follows.

      ///\code

      /// int count=0;

      /// for(Graph::InArcIt e(g, n); e!=INVALID; ++e) ++count;

      ///\endcode

      class InArcIt : public Arc {

      public:

        /// Default constructor

        /// @warning The default constructor sets the iterator

        /// to an undefined value.

        InArcIt() { }

        /// Copy constructor.

        /// Copy constructor.

        ///

        InArcIt(const InArcIt& e) : Arc(e) { }

        /// Initialize the iterator to be invalid.

        /// Initialize the iterator to be invalid.

        ///

        InArcIt(Invalid) { }

        /// This constructor sets the iterator to first incoming arc.

        /// This constructor set the iterator to the first incoming arc of

        /// the node.

        ///@param n the node

        ///@param g the graph

        InArcIt(const Graph& g, const Node& n) {

          ignore_unused_variable_warning(n);

          ignore_unused_variable_warning(g);

        }

        /// Arc -> InArcIt conversion

        /// Sets the iterator to the value of the trivial iterator \c e.

        /// This feature necessitates that each time we

        /// iterate the arc-set, the iteration order is the same.

        InArcIt(const Graph&, const Arc&) { }

        /// Next incoming arc

        /// Assign the iterator to the next inarc of the corresponding node.

        ///

        InArcIt& operator++() { return *this; }

      };

      ///

      template<class T>

      {

      public:

        ///\e

        NodeMap(const Graph&) { }

        ///\e

        NodeMap(const Graph&, T) { }

      private:

        ///Copy constructor

        ///Assignment operator

        template <typename CMap>

        NodeMap& operator=(const CMap&) {

          checkConcept<ReadMap<Node, T>, CMap>();

          return *this;

        }

      };

      ///

      template<class T>

      {

      public:

        ///\e

        ArcMap(const Graph&) { }

        ///\e

        ArcMap(const Graph&, T) { }

      private:

        ///Copy constructor

        ///Assignment operator

        template <typename CMap>

        ArcMap& operator=(const CMap&) {

          checkConcept<ReadMap<Arc, T>, CMap>();

          return *this;

        }

      };

      template<class T>

      {

      public:

        ///\e

        EdgeMap(const Graph&) { }

        ///\e

        EdgeMap(const Graph&, T) { }

      private:

        ///Copy constructor

        ///Assignment operator

        template <typename CMap>

        EdgeMap& operator=(const CMap&) {

          checkConcept<ReadMap<Edge, T>, CMap>();

          return *this;

        }

      };

      /// \brief Direct the given edge.

      ///

      /// Direct the given edge. The returned arc source

      /// will be the given node.

      Arc direct(const Edge&, const Node&) const {

        return INVALID;

      }

      /// \brief Direct the given edge.

      ///

      /// Direct the given edge. The returned arc

      /// represents the given edge and the direction comes

      /// from the bool parameter. The source of the edge and

      /// the directed arc is the same when the given bool is true.

      Arc direct(const Edge&, bool) const {

        return INVALID;

      }

      /// \brief Returns true if the arc has default orientation.

      ///

      /// Returns whether the given directed arc is same orientation as

      /// the corresponding edge's default orientation.

      bool direction(Arc) const { return true; }

      /// \brief Returns the opposite directed arc.

      ///

      /// Returns the opposite directed arc.

      Arc oppositeArc(Arc) const { return INVALID; }

      /// \brief Opposite node on an arc

      ///

      /// \return The opposite of the given node on the given edge.

      Node oppositeNode(Node, Edge) const { return INVALID; }

      /// \brief First node of the edge.

      ///

      /// \return The first node of the given edge.

      ///

      /// Naturally edges don't have direction and thus

      /// don't have source and target node. However we use \c u() and \c v()

      /// methods to query the two nodes of the arc. The direction of the

      /// arc which arises this way is called the inherent direction of the

      /// edge, and is used to define the "default" direction

      /// of the directed versions of the arcs.

      /// \sa v()

      /// \sa direction()

      Node u(Edge) const { return INVALID; }

      /// \brief Second node of the edge.

      ///

      /// \return The second node of the given edge.

      ///

      /// Naturally edges don't have direction and thus

      /// don't have source and target node. However we use \c u() and \c v()

      /// methods to query the two nodes of the arc. The direction of the

      /// arc which arises this way is called the inherent direction of the

      /// edge, and is used to define the "default" direction

      /// of the directed versions of the arcs.

      /// \sa u()

      /// \sa direction()

      Node v(Edge) const { return INVALID; }

      /// \brief Source node of the directed arc.

      Node source(Arc) const { return INVALID; }

      /// \brief Target node of the directed arc.

      Node target(Arc) const { return INVALID; }

      /// \brief Returns the id of the node.

      int id(Node) const { return -1; }

      /// \brief Returns the id of the edge.

      int id(Edge) const { return -1; }

      /// \brief Returns the id of the arc.

      int id(Arc) const { return -1; }

      /// \brief Returns the node with the given id.

      ///

      /// \pre The argument should be a valid node id in the graph.

      Node nodeFromId(int) const { return INVALID; }

      /// \brief Returns the edge with the given id.

      ///

      /// \pre The argument should be a valid edge id in the graph.

      Edge edgeFromId(int) const { return INVALID; }

      /// \brief Returns the arc with the given id.

      ///

      /// \pre The argument should be a valid arc id in the graph.

      Arc arcFromId(int) const { return INVALID; }

      /// \brief Returns an upper bound on the node IDs.

      int maxNodeId() const { return -1; }

      /// \brief Returns an upper bound on the edge IDs.

      int maxEdgeId() const { return -1; }

      /// \brief Returns an upper bound on the arc IDs.

      int maxArcId() const { return -1; }

      void first(Node&) const {}

      void next(Node&) const {}

      void first(Edge&) const {}

      void next(Edge&) const {}

      void first(Arc&) const {}

      void next(Arc&) const {}

      void firstOut(Arc&, Node) const {}

      void nextOut(Arc&) const {}

      void firstIn(Arc&, Node) const {}

      void nextIn(Arc&) const {}

      void firstInc(Edge &, bool &, const Node &) const {}

      void nextInc(Edge &, bool &) const {}

      // The second parameter is dummy.

      Node fromId(int, Node) const { return INVALID; }

      // The second parameter is dummy.

      Edge fromId(int, Edge) const { return INVALID; }

      // The second parameter is dummy.

      Arc fromId(int, Arc) const { return INVALID; }

      // Dummy parameter.

      int maxId(Node) const { return -1; }

      // Dummy parameter.

      int maxId(Edge) const { return -1; }

      // Dummy parameter.

      int maxId(Arc) const { return -1; }

      /// \brief Base node of the iterator

      ///

      /// Returns the base node (the source in this case) of the iterator

      Node baseNode(OutArcIt e) const {

        return source(e);

      }

      /// \brief Running node of the iterator

      ///

      /// Returns the running node (the target in this case) of the

      /// iterator

      Node runningNode(OutArcIt e) const {

        return target(e);

      }

      /// \brief Base node of the iterator

      ///

      /// Returns the base node (the target in this case) of the iterator

      Node baseNode(InArcIt e) const {

        return target(e);

      }

      /// \brief Running node of the iterator

      ///

      /// Returns the running node (the source in this case) of the

      /// iterator

      Node runningNode(InArcIt e) const {

        return source(e);

      }

      /// \brief Base node of the iterator

      ///

      /// Returns the base node of the iterator

      Node baseNode(IncEdgeIt) const {

        return INVALID;

      }

      /// \brief Running node of the iterator

      ///

      /// Returns the running node of the iterator

      Node runningNode(IncEdgeIt) const {

        return INVALID;

      }

      template <typename _Graph>

      struct Constraints {

        void constraints() {

          checkConcept<IterableGraphComponent<>, _Graph>();

          checkConcept<IDableGraphComponent<>, _Graph>();

          checkConcept<MappableGraphComponent<>, _Graph>();

        }

      };

    };

  }

}

#endif

            }

            {

              graph.firstInc(edge, dir, node);

              graph.nextInc(edge, dir);

            }

          }