/* -*- C++ -*-

  *

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

  *

  * Copyright (C) 2003-2008

  * 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_GRAPH_ADAPTOR_H

 #define LEMON_GRAPH_ADAPTOR_H

 ///\ingroup graph_adaptors

 ///\file

 ///\brief Several graph adaptors.

 ///

 ///This file contains several useful undirected graph adaptor classes.

 #include <lemon/core.h>

 #include <lemon/maps.h>

 #include <lemon/bits/graph_adaptor_extender.h>

 namespace lemon {

   template<typename _Graph>

   class GraphAdaptorBase {

   public:

     typedef _Graph Graph;

     typedef Graph ParentGraph;

   protected:

     Graph* _graph;

     GraphAdaptorBase() : _graph(0) {}

     void setGraph(Graph& graph) { _graph = &graph; }

   public:

     GraphAdaptorBase(Graph& graph) : _graph(&graph) {}

     typedef typename Graph::Node Node;

     typedef typename Graph::Arc Arc;

     typedef typename Graph::Edge Edge;

     void first(Node& i) const { _graph->first(i); }

     void first(Arc& i) const { _graph->first(i); }

     void first(Edge& i) const { _graph->first(i); }

     void firstIn(Arc& i, const Node& n) const { _graph->firstIn(i, n); }

     void firstOut(Arc& i, const Node& n ) const { _graph->firstOut(i, n); }

     void firstInc(Edge &i, bool &d, const Node &n) const {

       _graph->firstInc(i, d, n);

     }

     void next(Node& i) const { _graph->next(i); }

     void next(Arc& i) const { _graph->next(i); }

     void next(Edge& i) const { _graph->next(i); }

     void nextIn(Arc& i) const { _graph->nextIn(i); }

     void nextOut(Arc& i) const { _graph->nextOut(i); }

     void nextInc(Edge &i, bool &d) const { _graph->nextInc(i, d); }

     Node u(const Edge& e) const { return _graph->u(e); }

     Node v(const Edge& e) const { return _graph->v(e); }

     Node source(const Arc& a) const { return _graph->source(a); }

     Node target(const Arc& a) const { return _graph->target(a); }

     typedef NodeNumTagIndicator<Graph> NodeNumTag;

     int nodeNum() const { return _graph->nodeNum(); }

     typedef EdgeNumTagIndicator<Graph> EdgeNumTag;

     int arcNum() const { return _graph->arcNum(); }

     int edgeNum() const { return _graph->edgeNum(); }

     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;

     Arc findArc(const Node& u, const Node& v, const Arc& prev = INVALID) {

       return _graph->findArc(u, v, prev);

     }

     Edge findEdge(const Node& u, const Node& v, const Edge& prev = INVALID) {

       return _graph->findEdge(u, v, prev);

     }

     Node addNode() { return _graph->addNode(); }

     Edge addEdge(const Node& u, const Node& v) { return _graph->addEdge(u, v); }

     void erase(const Node& i) { _graph->erase(i); }

     void erase(const Edge& i) { _graph->erase(i); }

     void clear() { _graph->clear(); }

     bool direction(const Arc& a) const { return _graph->direction(a); }

     Arc direct(const Edge& e, bool d) const { return _graph->direct(e, d); }

     int id(const Node& v) const { return _graph->id(v); }

     int id(const Arc& a) const { return _graph->id(a); }

     int id(const Edge& e) const { return _graph->id(e); }

     Node nodeFromId(int ix) const { return _graph->nodeFromId(ix); }

     Arc arcFromId(int ix) const { return _graph->arcFromId(ix); }

     Edge edgeFromId(int ix) const { return _graph->edgeFromId(ix); }

     int maxNodeId() const { return _graph->maxNodeId(); }

     int maxArcId() const { return _graph->maxArcId(); }

     int maxEdgeId() const { return _graph->maxEdgeId(); }

     typedef typename ItemSetTraits<Graph, Node>::ItemNotifier NodeNotifier;

     NodeNotifier& notifier(Node) const { return _graph->notifier(Node()); } 

     typedef typename ItemSetTraits<Graph, Arc>::ItemNotifier ArcNotifier;

     ArcNotifier& notifier(Arc) const { return _graph->notifier(Arc()); } 

     typedef typename ItemSetTraits<Graph, Edge>::ItemNotifier EdgeNotifier;

     EdgeNotifier& notifier(Edge) const { return _graph->notifier(Edge()); } 

     template <typename _Value>

     class NodeMap : public Graph::template NodeMap<_Value> {

     public:

       typedef typename Graph::template NodeMap<_Value> Parent;

       explicit NodeMap(const GraphAdaptorBase<Graph>& adapter) 

 	: Parent(*adapter._graph) {}

       NodeMap(const GraphAdaptorBase<Graph>& adapter, const _Value& value)

 	: Parent(*adapter._graph, value) {}

     private:

       NodeMap& operator=(const NodeMap& cmap) {

 	return operator=<NodeMap>(cmap);

       }

       template <typename CMap>

       NodeMap& operator=(const CMap& cmap) {

         Parent::operator=(cmap);

         return *this;

       }

     };

     template <typename _Value>

     class ArcMap : public Graph::template ArcMap<_Value> {

     public:

       typedef typename Graph::template ArcMap<_Value> Parent;

       explicit ArcMap(const GraphAdaptorBase<Graph>& adapter) 

 	: Parent(*adapter._graph) {}

       ArcMap(const GraphAdaptorBase<Graph>& adapter, const _Value& value)

 	: Parent(*adapter._graph, value) {}

     private:

       ArcMap& operator=(const ArcMap& cmap) {

 	return operator=<ArcMap>(cmap);

       }

       template <typename CMap>

       ArcMap& operator=(const CMap& cmap) {

         Parent::operator=(cmap);

 	return *this;

       }

     };

     template <typename _Value>

     class EdgeMap : public Graph::template EdgeMap<_Value> {

     public:

       typedef typename Graph::template EdgeMap<_Value> Parent;

       explicit EdgeMap(const GraphAdaptorBase<Graph>& adapter) 

 	: Parent(*adapter._graph) {}

       EdgeMap(const GraphAdaptorBase<Graph>& adapter, const _Value& value)

 	: Parent(*adapter._graph, value) {}

     private:

       EdgeMap& operator=(const EdgeMap& cmap) {

 	return operator=<EdgeMap>(cmap);

       }

       template <typename CMap>

       EdgeMap& operator=(const CMap& cmap) {

         Parent::operator=(cmap);

         return *this;

       }

     };

   };

   template <typename _Graph, typename NodeFilterMap, 

 	    typename EdgeFilterMap, bool checked = true>

   class SubGraphAdaptorBase : public GraphAdaptorBase<_Graph> {

   public:

     typedef _Graph Graph;

     typedef SubGraphAdaptorBase Adaptor;

     typedef GraphAdaptorBase<_Graph> Parent;

   protected:

     NodeFilterMap* _node_filter_map;

     EdgeFilterMap* _edge_filter_map;

     SubGraphAdaptorBase() 

       : Parent(), _node_filter_map(0), _edge_filter_map(0) { }

     void setNodeFilterMap(NodeFilterMap& node_filter_map) {

       _node_filter_map=&node_filter_map;

     }

     void setEdgeFilterMap(EdgeFilterMap& edge_filter_map) {

       _edge_filter_map=&edge_filter_map;

     }

   public:

     typedef typename Parent::Node Node;

     typedef typename Parent::Arc Arc;

     typedef typename Parent::Edge Edge;

     void first(Node& i) const { 

       Parent::first(i); 

       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i); 

     }

     void first(Arc& i) const { 

       Parent::first(i); 

       while (i!=INVALID && (!(*_edge_filter_map)[i] 

 	     || !(*_node_filter_map)[Parent::source(i)]

 	     || !(*_node_filter_map)[Parent::target(i)])) Parent::next(i); 

     }

     void first(Edge& i) const { 

       Parent::first(i); 

       while (i!=INVALID && (!(*_edge_filter_map)[i] 

 	     || !(*_node_filter_map)[Parent::u(i)]

 	     || !(*_node_filter_map)[Parent::v(i)])) Parent::next(i); 

     }

     void firstIn(Arc& i, const Node& n) const { 

       Parent::firstIn(i, n); 

       while (i!=INVALID && (!(*_edge_filter_map)[i] 

 	     || !(*_node_filter_map)[Parent::source(i)])) Parent::nextIn(i); 

     }

     void firstOut(Arc& i, const Node& n) const { 

       Parent::firstOut(i, n); 

       while (i!=INVALID && (!(*_edge_filter_map)[i] 

 	     || !(*_node_filter_map)[Parent::target(i)])) Parent::nextOut(i); 

     }

     void firstInc(Edge& i, bool& d, const Node& n) const { 

       Parent::firstInc(i, d, n); 

       while (i!=INVALID && (!(*_edge_filter_map)[i] 

             || !(*_node_filter_map)[Parent::u(i)]

             || !(*_node_filter_map)[Parent::v(i)])) Parent::nextInc(i, d); 

     }

     void next(Node& i) const { 

       Parent::next(i); 

       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i); 

     }

     void next(Arc& i) const { 

       Parent::next(i); 

       while (i!=INVALID && (!(*_edge_filter_map)[i] 

 	     || !(*_node_filter_map)[Parent::source(i)]

 	     || !(*_node_filter_map)[Parent::target(i)])) Parent::next(i); 

     }

     void next(Edge& i) const { 

       Parent::next(i); 

       while (i!=INVALID && (!(*_edge_filter_map)[i] 

 	     || !(*_node_filter_map)[Parent::u(i)]

 	     || !(*_node_filter_map)[Parent::v(i)])) Parent::next(i); 

     }

     void nextIn(Arc& i) const { 

       Parent::nextIn(i); 

       while (i!=INVALID && (!(*_edge_filter_map)[i] 

 	     || !(*_node_filter_map)[Parent::source(i)])) Parent::nextIn(i); 

     }

     void nextOut(Arc& i) const { 

       Parent::nextOut(i); 

       while (i!=INVALID && (!(*_edge_filter_map)[i] 

 	     || !(*_node_filter_map)[Parent::target(i)])) Parent::nextOut(i); 

     }

     void nextInc(Edge& i, bool& d) const { 

       Parent::nextInc(i, d); 

       while (i!=INVALID && (!(*_edge_filter_map)[i]

             || !(*_node_filter_map)[Parent::u(i)]

             || !(*_node_filter_map)[Parent::v(i)])) Parent::nextInc(i, d); 

     }

     void hide(const Node& n) const { _node_filter_map->set(n, false); }

     void hide(const Edge& e) const { _edge_filter_map->set(e, false); }

     void unHide(const Node& n) const { _node_filter_map->set(n, true); }

     void unHide(const Edge& e) const { _edge_filter_map->set(e, true); }

     bool hidden(const Node& n) const { return !(*_node_filter_map)[n]; }

     bool hidden(const Edge& e) const { return !(*_edge_filter_map)[e]; }

     typedef False NodeNumTag;

     typedef False EdgeNumTag;

     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;

     Arc findArc(const Node& u, const Node& v, 

 		  const Arc& prev = INVALID) {

       if (!(*_node_filter_map)[u] || !(*_node_filter_map)[v]) {

         return INVALID;

       }

       Arc arc = Parent::findArc(u, v, prev);

       while (arc != INVALID && !(*_edge_filter_map)[arc]) {

         arc = Parent::findArc(u, v, arc);

       }

       return arc;

     }

     Edge findEdge(const Node& u, const Node& v, 

 		  const Edge& prev = INVALID) {

       if (!(*_node_filter_map)[u] || !(*_node_filter_map)[v]) {

         return INVALID;

       }

       Edge edge = Parent::findEdge(u, v, prev);

       while (edge != INVALID && !(*_edge_filter_map)[edge]) {

         edge = Parent::findEdge(u, v, edge);

       }

       return edge;

     }

     template <typename _Value>

     class NodeMap : public SubMapExtender<Adaptor, 

         typename Parent::template NodeMap<_Value> > {

     public:

       typedef _Value Value;

       typedef SubMapExtender<Adaptor, typename Parent::

                              template NodeMap<Value> > MapParent;

       NodeMap(const Adaptor& adaptor) 

 	: MapParent(adaptor) {}

       NodeMap(const Adaptor& adaptor, const Value& value) 

 	: MapParent(adaptor, value) {}

     private:

       NodeMap& operator=(const NodeMap& cmap) {

 	return operator=<NodeMap>(cmap);

       }

       template <typename CMap>

       NodeMap& operator=(const CMap& cmap) {

         MapParent::operator=(cmap);

 	return *this;

       }

     };

     template <typename _Value>

     class ArcMap : public SubMapExtender<Adaptor, 

 	typename Parent::template ArcMap<_Value> > {

     public:

       typedef _Value Value;

       typedef SubMapExtender<Adaptor, typename Parent::

                              template ArcMap<Value> > MapParent;

       ArcMap(const Adaptor& adaptor) 

 	: MapParent(adaptor) {}

       ArcMap(const Adaptor& adaptor, const Value& value) 

 	: MapParent(adaptor, value) {}

     private:

       ArcMap& operator=(const ArcMap& cmap) {

 	return operator=<ArcMap>(cmap);

       }

       template <typename CMap>

       ArcMap& operator=(const CMap& cmap) {

         MapParent::operator=(cmap);

 	return *this;

       }

     };

     template <typename _Value>

     class EdgeMap : public SubMapExtender<Adaptor, 

         typename Parent::template EdgeMap<_Value> > {

     public:

       typedef _Value Value;

       typedef SubMapExtender<Adaptor, typename Parent::

                              template EdgeMap<Value> > MapParent;

       EdgeMap(const Adaptor& adaptor) 

 	: MapParent(adaptor) {}

       EdgeMap(const Adaptor& adaptor, const Value& value) 

 	: MapParent(adaptor, value) {}

     private:

       EdgeMap& operator=(const EdgeMap& cmap) {

 	return operator=<EdgeMap>(cmap);

       }

       template <typename CMap>

       EdgeMap& operator=(const CMap& cmap) {

         MapParent::operator=(cmap);

 	return *this;

       }

     };

   };

   template <typename _Graph, typename NodeFilterMap, typename EdgeFilterMap>

   class SubGraphAdaptorBase<_Graph, NodeFilterMap, EdgeFilterMap, false> 

     : public GraphAdaptorBase<_Graph> {

   public:

     typedef _Graph Graph;

     typedef SubGraphAdaptorBase Adaptor;

     typedef GraphAdaptorBase<_Graph> Parent;

   protected:

     NodeFilterMap* _node_filter_map;

     EdgeFilterMap* _edge_filter_map;

     SubGraphAdaptorBase() : Parent(), 

 			    _node_filter_map(0), _edge_filter_map(0) { }

     void setNodeFilterMap(NodeFilterMap& node_filter_map) {

       _node_filter_map=&node_filter_map;

     }

     void setEdgeFilterMap(EdgeFilterMap& edge_filter_map) {

       _edge_filter_map=&edge_filter_map;

     }

   public:

     typedef typename Parent::Node Node;

     typedef typename Parent::Arc Arc;

     typedef typename Parent::Edge Edge;

     void first(Node& i) const { 

       Parent::first(i); 

       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i); 

     }

     void first(Arc& i) const { 

       Parent::first(i); 

       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i); 

     }

     void first(Edge& i) const { 

       Parent::first(i); 

       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i); 

     }

     void firstIn(Arc& i, const Node& n) const { 

       Parent::firstIn(i, n); 

       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextIn(i); 

     }

     void firstOut(Arc& i, const Node& n) const { 

       Parent::firstOut(i, n); 

       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextOut(i); 

     }

     void firstInc(Edge& i, bool& d, const Node& n) const { 

       Parent::firstInc(i, d, n); 

       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextInc(i, d); 

     }

     void next(Node& i) const { 

       Parent::next(i); 

       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i); 

     }

     void next(Arc& i) const { 

       Parent::next(i); 

       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i); 

     }

     void next(Edge& i) const { 

       Parent::next(i); 

       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i); 

     }

     void nextIn(Arc& i) const { 

       Parent::nextIn(i); 

       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextIn(i); 

     }

     void nextOut(Arc& i) const { 

       Parent::nextOut(i); 

       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextOut(i); 

     }

     void nextInc(Edge& i, bool& d) const { 

       Parent::nextInc(i, d); 

       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextInc(i, d); 

     }

     void hide(const Node& n) const { _node_filter_map->set(n, false); }

     void hide(const Edge& e) const { _edge_filter_map->set(e, false); }

     void unHide(const Node& n) const { _node_filter_map->set(n, true); }

     void unHide(const Edge& e) const { _edge_filter_map->set(e, true); }

     bool hidden(const Node& n) const { return !(*_node_filter_map)[n]; }

     bool hidden(const Edge& e) const { return !(*_edge_filter_map)[e]; }

     typedef False NodeNumTag;

     typedef False EdgeNumTag;

     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;

     Arc findArc(const Node& u, const Node& v, 

 		  const Arc& prev = INVALID) {

       Arc arc = Parent::findArc(u, v, prev);

       while (arc != INVALID && !(*_edge_filter_map)[arc]) {

         arc = Parent::findArc(u, v, arc);

       }

       return arc;

     }

     Edge findEdge(const Node& u, const Node& v, 

 		  const Edge& prev = INVALID) {

       Edge edge = Parent::findEdge(u, v, prev);

       while (edge != INVALID && !(*_edge_filter_map)[edge]) {

         edge = Parent::findEdge(u, v, edge);

       }

       return edge;

     }

     template <typename _Value>

     class NodeMap : public SubMapExtender<Adaptor, 

         typename Parent::template NodeMap<_Value> > {

     public:

       typedef _Value Value;

       typedef SubMapExtender<Adaptor, typename Parent::

                              template NodeMap<Value> > MapParent;

       NodeMap(const Adaptor& adaptor) 

 	: MapParent(adaptor) {}

       NodeMap(const Adaptor& adaptor, const Value& value) 

 	: MapParent(adaptor, value) {}

     private:

       NodeMap& operator=(const NodeMap& cmap) {

 	return operator=<NodeMap>(cmap);

       }

       template <typename CMap>

       NodeMap& operator=(const CMap& cmap) {

         MapParent::operator=(cmap);

 	return *this;

       }

     };

     template <typename _Value>

     class ArcMap : public SubMapExtender<Adaptor, 

 	typename Parent::template ArcMap<_Value> > {

     public:

       typedef _Value Value;

       typedef SubMapExtender<Adaptor, typename Parent::

                              template ArcMap<Value> > MapParent;

       ArcMap(const Adaptor& adaptor) 

 	: MapParent(adaptor) {}

       ArcMap(const Adaptor& adaptor, const Value& value) 

 	: MapParent(adaptor, value) {}

     private:

       ArcMap& operator=(const ArcMap& cmap) {

 	return operator=<ArcMap>(cmap);

       }

       template <typename CMap>

       ArcMap& operator=(const CMap& cmap) {

         MapParent::operator=(cmap);

 	return *this;

       }

     };

     template <typename _Value>

     class EdgeMap : public SubMapExtender<Adaptor, 

         typename Parent::template EdgeMap<_Value> > {

     public:

       typedef _Value Value;

       typedef SubMapExtender<Adaptor, typename Parent::

                              template EdgeMap<Value> > MapParent;

       EdgeMap(const Adaptor& adaptor) 

 	: MapParent(adaptor) {}

       EdgeMap(const Adaptor& adaptor, const _Value& value) 

 	: MapParent(adaptor, value) {}

     private:

       EdgeMap& operator=(const EdgeMap& cmap) {

 	return operator=<EdgeMap>(cmap);

       }

       template <typename CMap>

       EdgeMap& operator=(const CMap& cmap) {

         MapParent::operator=(cmap);

 	return *this;

       }

     };

   };

   /// \ingroup graph_adaptors

   ///

   /// \brief A graph adaptor for hiding nodes and edges from an

   /// undirected graph.

   /// 

   /// SubGraphAdaptor shows the graph with filtered node-set and

   /// edge-set. If the \c checked parameter is true then it filters

   /// the edge-set to do not get invalid edges which incident node is

   /// filtered.

   /// 

   /// If the \c checked template parameter is false then we have to

   /// note that the node-iterator cares only the filter on the

   /// node-set, and the edge-iterator cares only the filter on the

   /// edge-set.  This way the edge-map should filter all arcs which

   /// has filtered end node.

   template<typename _Graph, typename NodeFilterMap, 

 	   typename EdgeFilterMap, bool checked = true>

   class SubGraphAdaptor : 

     public GraphAdaptorExtender<

     SubGraphAdaptorBase<_Graph, NodeFilterMap, EdgeFilterMap, checked> > {

   public:

     typedef _Graph Graph;

     typedef GraphAdaptorExtender<

       SubGraphAdaptorBase<_Graph, NodeFilterMap, EdgeFilterMap> > Parent;

     typedef typename Parent::Node Node;

     typedef typename Parent::Edge Edge;

   protected:

     SubGraphAdaptor() { }

   public:

     /// \brief Constructor

     ///

     /// Creates a sub-graph-adaptor for the given graph with

     /// given node and edge map filters.

     SubGraphAdaptor(Graph& _graph, NodeFilterMap& node_filter_map, 

 		    EdgeFilterMap& edge_filter_map) { 

       setGraph(_graph);

       setNodeFilterMap(node_filter_map);

       setEdgeFilterMap(edge_filter_map);

     }

     /// \brief Hides the node of the graph

     ///

     /// This function hides \c n in the digraph, i.e. the iteration 

     /// jumps over it. This is done by simply setting the value of \c n  

     /// to be false in the corresponding node-map.

     void hide(const Node& n) const { Parent::hide(n); }

     /// \brief Hides the edge of the graph

     ///

     /// This function hides \c e in the digraph, i.e. the iteration 

     /// jumps over it. This is done by simply setting the value of \c e

     /// to be false in the corresponding edge-map.

     void hide(const Edge& e) const { Parent::hide(e); }

     /// \brief Unhides the node of the graph

     ///

     /// The value of \c n is set to be true in the node-map which stores 

     /// hide information. If \c n was hidden previuosly, then it is shown 

     /// again

     void unHide(const Node& n) const { Parent::unHide(n); }

     /// \brief Unhides the edge of the graph

     ///

     /// The value of \c e is set to be true in the edge-map which stores 

     /// hide information. If \c e was hidden previuosly, then it is shown 

     /// again

     void unHide(const Edge& e) const { Parent::unHide(e); }

     /// \brief Returns true if \c n is hidden.

     ///

     /// Returns true if \c n is hidden.

     ///

     bool hidden(const Node& n) const { return Parent::hidden(n); }

     /// \brief Returns true if \c e is hidden.

     ///

     /// Returns true if \c e is hidden.

     ///

     bool hidden(const Edge& e) const { return Parent::hidden(e); }

   };

   /// \brief Just gives back a sub-graph adaptor

   ///

   /// Just gives back a sub-graph adaptor

   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>

   SubGraphAdaptor<const Graph, NodeFilterMap, ArcFilterMap>

   subGraphAdaptor(const Graph& graph, 

                    NodeFilterMap& nfm, ArcFilterMap& efm) {

     return SubGraphAdaptor<const Graph, NodeFilterMap, ArcFilterMap>

       (graph, nfm, efm);

   }

   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>

   SubGraphAdaptor<const Graph, const NodeFilterMap, ArcFilterMap>

   subGraphAdaptor(const Graph& graph, 

                    NodeFilterMap& nfm, ArcFilterMap& efm) {

     return SubGraphAdaptor<const Graph, const NodeFilterMap, ArcFilterMap>

       (graph, nfm, efm);

   }

   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>

   SubGraphAdaptor<const Graph, NodeFilterMap, const ArcFilterMap>

   subGraphAdaptor(const Graph& graph, 

                    NodeFilterMap& nfm, ArcFilterMap& efm) {

     return SubGraphAdaptor<const Graph, NodeFilterMap, const ArcFilterMap>

       (graph, nfm, efm);

   }

   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>

   SubGraphAdaptor<const Graph, const NodeFilterMap, const ArcFilterMap>

   subGraphAdaptor(const Graph& graph, 

                    NodeFilterMap& nfm, ArcFilterMap& efm) {

     return SubGraphAdaptor<const Graph, const NodeFilterMap, 

       const ArcFilterMap>(graph, nfm, efm);

   }

   /// \ingroup graph_adaptors

   ///

   /// \brief An adaptor for hiding nodes from an graph.

   ///

   /// An adaptor for hiding nodes from an graph.  This

   /// adaptor specializes SubGraphAdaptor in the way that only the

   /// node-set can be filtered. In usual case the checked parameter is

   /// true, we get the induced subgraph. But if the checked parameter

   /// is false then we can filter only isolated nodes.

   template<typename _Graph, typename _NodeFilterMap, bool checked = true>

   class NodeSubGraphAdaptor : 

     public SubGraphAdaptor<_Graph, _NodeFilterMap, 

 			   ConstMap<typename _Graph::Edge, bool>, checked> {

   public:

     typedef _Graph Graph;

     typedef _NodeFilterMap NodeFilterMap;

     typedef SubGraphAdaptor<Graph, NodeFilterMap, 

 			    ConstMap<typename Graph::Edge, bool> > Parent;

     typedef typename Parent::Node Node;

   protected:

     ConstMap<typename Graph::Edge, bool> const_true_map;

     NodeSubGraphAdaptor() : const_true_map(true) {

       Parent::setEdgeFilterMap(const_true_map);

     }

   public:

     /// \brief Constructor

     ///

     /// Creates a node-sub-graph-adaptor for the given graph with

     /// given node map filters.

     NodeSubGraphAdaptor(Graph& _graph, NodeFilterMap& node_filter_map) : 

       Parent(), const_true_map(true) { 

       Parent::setGraph(_graph);

       Parent::setNodeFilterMap(node_filter_map);

       Parent::setEdgeFilterMap(const_true_map);

     }

     /// \brief Hides the node of the graph

     ///

     /// This function hides \c n in the digraph, i.e. the iteration 

     /// jumps over it. This is done by simply setting the value of \c n  

     /// to be false in the corresponding node-map.

     void hide(const Node& n) const { Parent::hide(n); }

     /// \brief Unhides the node of the graph

     ///

     /// The value of \c n is set to be true in the node-map which stores 

     /// hide information. If \c n was hidden previuosly, then it is shown 

     /// again

     void unHide(const Node& n) const { Parent::unHide(n); }

     /// \brief Returns true if \c n is hidden.

     ///

     /// Returns true if \c n is hidden.

     ///

     bool hidden(const Node& n) const { return Parent::hidden(n); }

   };

   /// \brief Just gives back a node-sub-graph adaptor

   ///

   /// Just gives back a node-sub-graph adaptor

   template<typename Graph, typename NodeFilterMap>

   NodeSubGraphAdaptor<const Graph, NodeFilterMap>

   nodeSubGraphAdaptor(const Graph& graph, NodeFilterMap& nfm) {

     return NodeSubGraphAdaptor<const Graph, NodeFilterMap>(graph, nfm);

   }

   template<typename Graph, typename NodeFilterMap>

   NodeSubGraphAdaptor<const Graph, const NodeFilterMap>

   nodeSubGraphAdaptor(const Graph& graph, const NodeFilterMap& nfm) {

     return NodeSubGraphAdaptor<const Graph, const NodeFilterMap>(graph, nfm);

   }

   /// \ingroup graph_adaptors

   ///

   /// \brief An adaptor for hiding edges from an graph.

   ///

   /// \warning Graph adaptors are in even more experimental state

   /// than the other parts of the lib. Use them at you own risk.

   ///

   /// An adaptor for hiding edges from an graph.

   /// This adaptor specializes SubGraphAdaptor in the way that

   /// only the arc-set 

   /// can be filtered.

   template<typename _Graph, typename _EdgeFilterMap>

   class EdgeSubGraphAdaptor : 

     public SubGraphAdaptor<_Graph, ConstMap<typename _Graph::Node,bool>, 

                            _EdgeFilterMap, false> {

   public:

     typedef _Graph Graph;

     typedef _EdgeFilterMap EdgeFilterMap;

     typedef SubGraphAdaptor<Graph, ConstMap<typename Graph::Node,bool>, 

 			    EdgeFilterMap, false> Parent;

     typedef typename Parent::Edge Edge;

   protected:

     ConstMap<typename Graph::Node, bool> const_true_map;

     EdgeSubGraphAdaptor() : const_true_map(true) {

       Parent::setNodeFilterMap(const_true_map);

     }

   public:

     /// \brief Constructor

     ///

     /// Creates a edge-sub-graph-adaptor for the given graph with

     /// given node map filters.

     EdgeSubGraphAdaptor(Graph& _graph, EdgeFilterMap& edge_filter_map) : 

       Parent(), const_true_map(true) { 

       Parent::setGraph(_graph);

       Parent::setNodeFilterMap(const_true_map);

       Parent::setEdgeFilterMap(edge_filter_map);

     }

     /// \brief Hides the edge of the graph

     ///

     /// This function hides \c e in the digraph, i.e. the iteration 

     /// jumps over it. This is done by simply setting the value of \c e

     /// to be false in the corresponding edge-map.

     void hide(const Edge& e) const { Parent::hide(e); }

     /// \brief Unhides the edge of the graph

     ///

     /// The value of \c e is set to be true in the edge-map which stores 

     /// hide information. If \c e was hidden previuosly, then it is shown 

     /// again

     void unHide(const Edge& e) const { Parent::unHide(e); }

     /// \brief Returns true if \c e is hidden.

     ///

     /// Returns true if \c e is hidden.

     ///

     bool hidden(const Edge& e) const { return Parent::hidden(e); }

   };

   /// \brief Just gives back an edge-sub-graph adaptor

   ///

   /// Just gives back an edge-sub-graph adaptor

   template<typename Graph, typename EdgeFilterMap>

   EdgeSubGraphAdaptor<const Graph, EdgeFilterMap>

   edgeSubGraphAdaptor(const Graph& graph, EdgeFilterMap& efm) {

     return EdgeSubGraphAdaptor<const Graph, EdgeFilterMap>(graph, efm);

   }

   template<typename Graph, typename EdgeFilterMap>

   EdgeSubGraphAdaptor<const Graph, const EdgeFilterMap>

   edgeSubGraphAdaptor(const Graph& graph, const EdgeFilterMap& efm) {

     return EdgeSubGraphAdaptor<const Graph, const EdgeFilterMap>(graph, efm);

   }

   template <typename _Graph, typename _DirectionMap>

   class DirGraphAdaptorBase {

   public:

     typedef _Graph Graph;

     typedef _DirectionMap DirectionMap;

     typedef typename Graph::Node Node;

     typedef typename Graph::Edge Arc;

     /// \brief Reverse arc

     /// 

     /// It reverse the given arc. It simply negate the direction in the map.

     void reverseArc(const Arc& arc) {

       _direction->set(arc, !(*_direction)[arc]);

     }

     void first(Node& i) const { _graph->first(i); }

     void first(Arc& i) const { _graph->first(i); }

     void firstIn(Arc& i, const Node& n) const {

       bool d;

       _graph->firstInc(i, d, n);

       while (i != INVALID && d == (*_direction)[i]) _graph->nextInc(i, d);

     }

     void firstOut(Arc& i, const Node& n ) const { 

       bool d;

       _graph->firstInc(i, d, n);

       while (i != INVALID && d != (*_direction)[i]) _graph->nextInc(i, d);

     }

     void next(Node& i) const { _graph->next(i); }

     void next(Arc& i) const { _graph->next(i); }

     void nextIn(Arc& i) const {

       bool d = !(*_direction)[i];

       _graph->nextInc(i, d);

       while (i != INVALID && d == (*_direction)[i]) _graph->nextInc(i, d);

     }

     void nextOut(Arc& i) const {

       bool d = (*_direction)[i];

       _graph->nextInc(i, d);

       while (i != INVALID && d != (*_direction)[i]) _graph->nextInc(i, d);

     }

     Node source(const Arc& e) const { 

       return (*_direction)[e] ? _graph->u(e) : _graph->v(e); 

     }

     Node target(const Arc& e) const { 

       return (*_direction)[e] ? _graph->v(e) : _graph->u(e); 

     }

     typedef NodeNumTagIndicator<Graph> NodeNumTag;

     int nodeNum() const { return _graph->nodeNum(); }

     typedef EdgeNumTagIndicator<Graph> EdgeNumTag;

     int arcNum() const { return _graph->edgeNum(); }

     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;

     Arc findArc(const Node& u, const Node& v, 

 		  const Arc& prev = INVALID) {

       Arc arc = prev;

       bool d = arc == INVALID ? true : (*_direction)[arc];

       if (d) {

         arc = _graph->findEdge(u, v, arc);

         while (arc != INVALID && !(*_direction)[arc]) {

           _graph->findEdge(u, v, arc);

         }

         if (arc != INVALID) return arc;

       }

       _graph->findEdge(v, u, arc);

       while (arc != INVALID && (*_direction)[arc]) {

         _graph->findEdge(u, v, arc);

       }

       return arc;

     }

     Node addNode() { 

       return Node(_graph->addNode()); 

     }

     Arc addArc(const Node& u, const Node& v) {

       Arc arc = _graph->addArc(u, v);

       _direction->set(arc, _graph->source(arc) == u);

       return arc; 

     }

     void erase(const Node& i) { _graph->erase(i); }

     void erase(const Arc& i) { _graph->erase(i); }

     void clear() { _graph->clear(); }

     int id(const Node& v) const { return _graph->id(v); }

     int id(const Arc& e) const { return _graph->id(e); }

     Node nodeFromId(int idx) const { return _graph->nodeFromId(idx); }

     Arc arcFromId(int idx) const { return _graph->edgeFromId(idx); }

     int maxNodeId() const { return _graph->maxNodeId(); }

     int maxArcId() const { return _graph->maxEdgeId(); }

     typedef typename ItemSetTraits<Graph, Node>::ItemNotifier NodeNotifier;

     NodeNotifier& notifier(Node) const { return _graph->notifier(Node()); } 

     typedef typename ItemSetTraits<Graph, Arc>::ItemNotifier ArcNotifier;

     ArcNotifier& notifier(Arc) const { return _graph->notifier(Arc()); } 

     template <typename _Value>

     class NodeMap : public _Graph::template NodeMap<_Value> {

     public:

       typedef typename _Graph::template NodeMap<_Value> Parent;

       explicit NodeMap(const DirGraphAdaptorBase& adapter) 

 	: Parent(*adapter._graph) {}

       NodeMap(const DirGraphAdaptorBase& adapter, const _Value& value)

 	: Parent(*adapter._graph, value) {}

     private:

       NodeMap& operator=(const NodeMap& cmap) {

         return operator=<NodeMap>(cmap);

       }

       template <typename CMap>

       NodeMap& operator=(const CMap& cmap) {

         Parent::operator=(cmap);

         return *this;

       }

     };

     template <typename _Value>

     class ArcMap : public _Graph::template EdgeMap<_Value> {

     public:

       typedef typename Graph::template EdgeMap<_Value> Parent;

       explicit ArcMap(const DirGraphAdaptorBase& adapter) 

 	: Parent(*adapter._graph) { }

       ArcMap(const DirGraphAdaptorBase& adapter, const _Value& value)

 	: Parent(*adapter._graph, value) { }

     private:

       ArcMap& operator=(const ArcMap& cmap) {

         return operator=<ArcMap>(cmap);

       }

       template <typename CMap>

       ArcMap& operator=(const CMap& cmap) {

         Parent::operator=(cmap);

         return *this;

       }

     };

   protected:

     Graph* _graph;

     DirectionMap* _direction;

     void setDirectionMap(DirectionMap& direction) {

       _direction = &direction;

     }

     void setGraph(Graph& graph) {

       _graph = &graph;

     }

   };

   /// \ingroup graph_adaptors

   ///

   /// \brief A directed graph is made from an graph by an adaptor

   ///

   /// This adaptor gives a direction for each edge in the undirected

   /// graph. The direction of the arcs stored in the

   /// DirectionMap. This map is a bool map on the edges. If

   /// the edge is mapped to true then the direction of the directed

   /// arc will be the same as the default direction of the edge. The

   /// arcs can be easily reverted by the \ref

   /// DirGraphAdaptorBase::reverseArc "reverseArc()" member in the

   /// adaptor.

   ///

   /// It can be used to solve orientation problems on directed graphs.

   /// For example how can we orient an graph to get the minimum

   /// number of strongly connected components. If we orient the arcs with

   /// the dfs algorithm out from the source then we will get such an 

   /// orientation. 

   ///

   /// We use the \ref DfsVisitor "visitor" interface of the 

   /// \ref DfsVisit "dfs" algorithm:

   ///\code

   /// template <typename DirMap>

   /// class OrientVisitor : public DfsVisitor<Graph> {

   /// public:

   ///

   ///   OrientVisitor(const Graph& graph, DirMap& dirMap)

   ///     : _graph(graph), _dirMap(dirMap), _processed(graph, false) {}

   ///

   ///   void discover(const Arc& arc) {

   ///     _processed.set(arc, true);

   ///     _dirMap.set(arc, _graph.direction(arc));

   ///   }

   ///

   ///   void examine(const Arc& arc) {

   ///     if (_processed[arc]) return;

   ///     _processed.set(arc, true);

   ///     _dirMap.set(arc, _graph.direction(arc));

   ///   }  

   /// 

   /// private:

   ///   const Graph& _graph;  

   ///   DirMap& _dirMap;

   ///   Graph::EdgeMap<bool> _processed;

   /// };

   ///\endcode

   ///

   /// And now we can use the orientation:

   ///\code

   /// Graph::EdgeMap<bool> dmap(graph);

   ///

   /// typedef OrientVisitor<Graph::EdgeMap<bool> > Visitor;

   /// Visitor visitor(graph, dmap);

   ///

   /// DfsVisit<Graph, Visitor> dfs(graph, visitor);

   ///

   /// dfs.run();

   ///

   /// typedef DirGraphAdaptor<Graph> DGraph;

   /// DGraph dgraph(graph, dmap);

   ///

   /// LEMON_ASSERT(countStronglyConnectedComponents(dgraph) == 

   ///              countBiArcConnectedComponents(graph), "Wrong Orientation");

   ///\endcode

   ///

   /// The number of the bi-connected components is a lower bound for

   /// the number of the strongly connected components in the directed

   /// graph because if we contract the bi-connected components to

   /// nodes we will get a tree therefore we cannot orient arcs in

   /// both direction between bi-connected components. In the other way

   /// the algorithm will orient one component to be strongly

   /// connected. The two relations proof that the assertion will

   /// be always true and the found solution is optimal.

   ///

   /// \sa DirGraphAdaptorBase

   /// \sa dirGraphAdaptor

   template<typename _Graph, 

            typename DirectionMap = typename _Graph::template EdgeMap<bool> > 

   class DirGraphAdaptor : 

     public DigraphAdaptorExtender<DirGraphAdaptorBase<_Graph, DirectionMap> > {

   public:

     typedef _Graph Graph;

     typedef DigraphAdaptorExtender<

       DirGraphAdaptorBase<_Graph, DirectionMap> > Parent;

     typedef typename Parent::Arc Arc;

   protected:

     DirGraphAdaptor() { }

   public:

     /// \brief Constructor of the adaptor

     ///

     /// Constructor of the adaptor

     DirGraphAdaptor(Graph& graph, DirectionMap& direction) { 

       setGraph(graph);

       setDirectionMap(direction);