lemon/graph_adaptor.h
changeset 432 76287c8caa26
parent 430 05357da973ce
equal deleted inserted replaced
1:36e6c0323ae6 -1:000000000000
     1 /* -*- C++ -*-
       
     2  *
       
     3  * This file is a part of LEMON, a generic C++ optimization library
       
     4  *
       
     5  * Copyright (C) 2003-2008
       
     6  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
       
     7  * (Egervary Research Group on Combinatorial Optimization, EGRES).
       
     8  *
       
     9  * Permission to use, modify and distribute this software is granted
       
    10  * provided that this copyright notice appears in all copies. For
       
    11  * precise terms see the accompanying LICENSE file.
       
    12  *
       
    13  * This software is provided "AS IS" with no warranty of any kind,
       
    14  * express or implied, and with no claim as to its suitability for any
       
    15  * purpose.
       
    16  *
       
    17  */
       
    18 
       
    19 #ifndef LEMON_GRAPH_ADAPTOR_H
       
    20 #define LEMON_GRAPH_ADAPTOR_H
       
    21 
       
    22 ///\ingroup graph_adaptors
       
    23 ///\file
       
    24 ///\brief Several graph adaptors.
       
    25 ///
       
    26 ///This file contains several useful undirected graph adaptor classes.
       
    27 
       
    28 #include <lemon/core.h>
       
    29 #include <lemon/maps.h>
       
    30 #include <lemon/bits/graph_adaptor_extender.h>
       
    31 
       
    32 namespace lemon {
       
    33 
       
    34   template<typename _Graph>
       
    35   class GraphAdaptorBase {
       
    36   public:
       
    37     typedef _Graph Graph;
       
    38     typedef Graph ParentGraph;
       
    39 
       
    40   protected:
       
    41     Graph* _graph;
       
    42 
       
    43     GraphAdaptorBase() : _graph(0) {}
       
    44 
       
    45     void setGraph(Graph& graph) { _graph = &graph; }
       
    46 
       
    47   public:
       
    48     GraphAdaptorBase(Graph& graph) : _graph(&graph) {}
       
    49  
       
    50     typedef typename Graph::Node Node;
       
    51     typedef typename Graph::Arc Arc;
       
    52     typedef typename Graph::Edge Edge;
       
    53    
       
    54     void first(Node& i) const { _graph->first(i); }
       
    55     void first(Arc& i) const { _graph->first(i); }
       
    56     void first(Edge& i) const { _graph->first(i); }
       
    57     void firstIn(Arc& i, const Node& n) const { _graph->firstIn(i, n); }
       
    58     void firstOut(Arc& i, const Node& n ) const { _graph->firstOut(i, n); }
       
    59     void firstInc(Edge &i, bool &d, const Node &n) const {
       
    60       _graph->firstInc(i, d, n);
       
    61     }
       
    62 
       
    63     void next(Node& i) const { _graph->next(i); }
       
    64     void next(Arc& i) const { _graph->next(i); }
       
    65     void next(Edge& i) const { _graph->next(i); }
       
    66     void nextIn(Arc& i) const { _graph->nextIn(i); }
       
    67     void nextOut(Arc& i) const { _graph->nextOut(i); }
       
    68     void nextInc(Edge &i, bool &d) const { _graph->nextInc(i, d); }
       
    69 
       
    70     Node u(const Edge& e) const { return _graph->u(e); }
       
    71     Node v(const Edge& e) const { return _graph->v(e); }
       
    72 
       
    73     Node source(const Arc& a) const { return _graph->source(a); }
       
    74     Node target(const Arc& a) const { return _graph->target(a); }
       
    75 
       
    76     typedef NodeNumTagIndicator<Graph> NodeNumTag;
       
    77     int nodeNum() const { return _graph->nodeNum(); }
       
    78     
       
    79     typedef EdgeNumTagIndicator<Graph> EdgeNumTag;
       
    80     int arcNum() const { return _graph->arcNum(); }
       
    81     int edgeNum() const { return _graph->edgeNum(); }
       
    82 
       
    83     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;
       
    84     Arc findArc(const Node& u, const Node& v, const Arc& prev = INVALID) {
       
    85       return _graph->findArc(u, v, prev);
       
    86     }
       
    87     Edge findEdge(const Node& u, const Node& v, const Edge& prev = INVALID) {
       
    88       return _graph->findEdge(u, v, prev);
       
    89     }
       
    90   
       
    91     Node addNode() { return _graph->addNode(); }
       
    92     Edge addEdge(const Node& u, const Node& v) { return _graph->addEdge(u, v); }
       
    93 
       
    94     void erase(const Node& i) { _graph->erase(i); }
       
    95     void erase(const Edge& i) { _graph->erase(i); }
       
    96   
       
    97     void clear() { _graph->clear(); }
       
    98     
       
    99     bool direction(const Arc& a) const { return _graph->direction(a); }
       
   100     Arc direct(const Edge& e, bool d) const { return _graph->direct(e, d); }
       
   101 
       
   102     int id(const Node& v) const { return _graph->id(v); }
       
   103     int id(const Arc& a) const { return _graph->id(a); }
       
   104     int id(const Edge& e) const { return _graph->id(e); }
       
   105 
       
   106     Node nodeFromId(int ix) const { return _graph->nodeFromId(ix); }
       
   107     Arc arcFromId(int ix) const { return _graph->arcFromId(ix); }
       
   108     Edge edgeFromId(int ix) const { return _graph->edgeFromId(ix); }
       
   109 
       
   110     int maxNodeId() const { return _graph->maxNodeId(); }
       
   111     int maxArcId() const { return _graph->maxArcId(); }
       
   112     int maxEdgeId() const { return _graph->maxEdgeId(); }
       
   113 
       
   114     typedef typename ItemSetTraits<Graph, Node>::ItemNotifier NodeNotifier;
       
   115     NodeNotifier& notifier(Node) const { return _graph->notifier(Node()); } 
       
   116 
       
   117     typedef typename ItemSetTraits<Graph, Arc>::ItemNotifier ArcNotifier;
       
   118     ArcNotifier& notifier(Arc) const { return _graph->notifier(Arc()); } 
       
   119 
       
   120     typedef typename ItemSetTraits<Graph, Edge>::ItemNotifier EdgeNotifier;
       
   121     EdgeNotifier& notifier(Edge) const { return _graph->notifier(Edge()); } 
       
   122 
       
   123     template <typename _Value>
       
   124     class NodeMap : public Graph::template NodeMap<_Value> {
       
   125     public:
       
   126       typedef typename Graph::template NodeMap<_Value> Parent;
       
   127       explicit NodeMap(const GraphAdaptorBase<Graph>& adapter) 
       
   128 	: Parent(*adapter._graph) {}
       
   129       NodeMap(const GraphAdaptorBase<Graph>& adapter, const _Value& value)
       
   130 	: Parent(*adapter._graph, value) {}
       
   131 
       
   132     private:
       
   133       NodeMap& operator=(const NodeMap& cmap) {
       
   134 	return operator=<NodeMap>(cmap);
       
   135       }
       
   136 
       
   137       template <typename CMap>
       
   138       NodeMap& operator=(const CMap& cmap) {
       
   139         Parent::operator=(cmap);
       
   140         return *this;
       
   141       }
       
   142       
       
   143     };
       
   144 
       
   145     template <typename _Value>
       
   146     class ArcMap : public Graph::template ArcMap<_Value> {
       
   147     public:
       
   148       typedef typename Graph::template ArcMap<_Value> Parent;
       
   149       explicit ArcMap(const GraphAdaptorBase<Graph>& adapter) 
       
   150 	: Parent(*adapter._graph) {}
       
   151       ArcMap(const GraphAdaptorBase<Graph>& adapter, const _Value& value)
       
   152 	: Parent(*adapter._graph, value) {}
       
   153 
       
   154     private:
       
   155       ArcMap& operator=(const ArcMap& cmap) {
       
   156 	return operator=<ArcMap>(cmap);
       
   157       }
       
   158 
       
   159       template <typename CMap>
       
   160       ArcMap& operator=(const CMap& cmap) {
       
   161         Parent::operator=(cmap);
       
   162 	return *this;
       
   163       }
       
   164     };
       
   165 
       
   166     template <typename _Value>
       
   167     class EdgeMap : public Graph::template EdgeMap<_Value> {
       
   168     public:
       
   169       typedef typename Graph::template EdgeMap<_Value> Parent;
       
   170       explicit EdgeMap(const GraphAdaptorBase<Graph>& adapter) 
       
   171 	: Parent(*adapter._graph) {}
       
   172       EdgeMap(const GraphAdaptorBase<Graph>& adapter, const _Value& value)
       
   173 	: Parent(*adapter._graph, value) {}
       
   174 
       
   175     private:
       
   176       EdgeMap& operator=(const EdgeMap& cmap) {
       
   177 	return operator=<EdgeMap>(cmap);
       
   178       }
       
   179 
       
   180       template <typename CMap>
       
   181       EdgeMap& operator=(const CMap& cmap) {
       
   182         Parent::operator=(cmap);
       
   183         return *this;
       
   184       }
       
   185     };
       
   186 
       
   187   };
       
   188 
       
   189   template <typename _Graph, typename NodeFilterMap, 
       
   190 	    typename EdgeFilterMap, bool checked = true>
       
   191   class SubGraphAdaptorBase : public GraphAdaptorBase<_Graph> {
       
   192   public:
       
   193     typedef _Graph Graph;
       
   194     typedef SubGraphAdaptorBase Adaptor;
       
   195     typedef GraphAdaptorBase<_Graph> Parent;
       
   196   protected:
       
   197 
       
   198     NodeFilterMap* _node_filter_map;
       
   199     EdgeFilterMap* _edge_filter_map;
       
   200 
       
   201     SubGraphAdaptorBase() 
       
   202       : Parent(), _node_filter_map(0), _edge_filter_map(0) { }
       
   203 
       
   204     void setNodeFilterMap(NodeFilterMap& node_filter_map) {
       
   205       _node_filter_map=&node_filter_map;
       
   206     }
       
   207     void setEdgeFilterMap(EdgeFilterMap& edge_filter_map) {
       
   208       _edge_filter_map=&edge_filter_map;
       
   209     }
       
   210 
       
   211   public:
       
   212 
       
   213     typedef typename Parent::Node Node;
       
   214     typedef typename Parent::Arc Arc;
       
   215     typedef typename Parent::Edge Edge;
       
   216 
       
   217     void first(Node& i) const { 
       
   218       Parent::first(i); 
       
   219       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i); 
       
   220     }
       
   221 
       
   222     void first(Arc& i) const { 
       
   223       Parent::first(i); 
       
   224       while (i!=INVALID && (!(*_edge_filter_map)[i] 
       
   225 	     || !(*_node_filter_map)[Parent::source(i)]
       
   226 	     || !(*_node_filter_map)[Parent::target(i)])) Parent::next(i); 
       
   227     }
       
   228 
       
   229     void first(Edge& i) const { 
       
   230       Parent::first(i); 
       
   231       while (i!=INVALID && (!(*_edge_filter_map)[i] 
       
   232 	     || !(*_node_filter_map)[Parent::u(i)]
       
   233 	     || !(*_node_filter_map)[Parent::v(i)])) Parent::next(i); 
       
   234     }
       
   235 
       
   236     void firstIn(Arc& i, const Node& n) const { 
       
   237       Parent::firstIn(i, n); 
       
   238       while (i!=INVALID && (!(*_edge_filter_map)[i] 
       
   239 	     || !(*_node_filter_map)[Parent::source(i)])) Parent::nextIn(i); 
       
   240     }
       
   241 
       
   242     void firstOut(Arc& i, const Node& n) const { 
       
   243       Parent::firstOut(i, n); 
       
   244       while (i!=INVALID && (!(*_edge_filter_map)[i] 
       
   245 	     || !(*_node_filter_map)[Parent::target(i)])) Parent::nextOut(i); 
       
   246     }
       
   247 
       
   248     void firstInc(Edge& i, bool& d, const Node& n) const { 
       
   249       Parent::firstInc(i, d, n); 
       
   250       while (i!=INVALID && (!(*_edge_filter_map)[i] 
       
   251             || !(*_node_filter_map)[Parent::u(i)]
       
   252             || !(*_node_filter_map)[Parent::v(i)])) Parent::nextInc(i, d); 
       
   253     }
       
   254 
       
   255     void next(Node& i) const { 
       
   256       Parent::next(i); 
       
   257       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i); 
       
   258     }
       
   259 
       
   260     void next(Arc& i) const { 
       
   261       Parent::next(i); 
       
   262       while (i!=INVALID && (!(*_edge_filter_map)[i] 
       
   263 	     || !(*_node_filter_map)[Parent::source(i)]
       
   264 	     || !(*_node_filter_map)[Parent::target(i)])) Parent::next(i); 
       
   265     }
       
   266 
       
   267     void next(Edge& i) const { 
       
   268       Parent::next(i); 
       
   269       while (i!=INVALID && (!(*_edge_filter_map)[i] 
       
   270 	     || !(*_node_filter_map)[Parent::u(i)]
       
   271 	     || !(*_node_filter_map)[Parent::v(i)])) Parent::next(i); 
       
   272     }
       
   273 
       
   274     void nextIn(Arc& i) const { 
       
   275       Parent::nextIn(i); 
       
   276       while (i!=INVALID && (!(*_edge_filter_map)[i] 
       
   277 	     || !(*_node_filter_map)[Parent::source(i)])) Parent::nextIn(i); 
       
   278     }
       
   279 
       
   280     void nextOut(Arc& i) const { 
       
   281       Parent::nextOut(i); 
       
   282       while (i!=INVALID && (!(*_edge_filter_map)[i] 
       
   283 	     || !(*_node_filter_map)[Parent::target(i)])) Parent::nextOut(i); 
       
   284     }
       
   285 
       
   286     void nextInc(Edge& i, bool& d) const { 
       
   287       Parent::nextInc(i, d); 
       
   288       while (i!=INVALID && (!(*_edge_filter_map)[i]
       
   289             || !(*_node_filter_map)[Parent::u(i)]
       
   290             || !(*_node_filter_map)[Parent::v(i)])) Parent::nextInc(i, d); 
       
   291     }
       
   292 
       
   293     void hide(const Node& n) const { _node_filter_map->set(n, false); }
       
   294     void hide(const Edge& e) const { _edge_filter_map->set(e, false); }
       
   295 
       
   296     void unHide(const Node& n) const { _node_filter_map->set(n, true); }
       
   297     void unHide(const Edge& e) const { _edge_filter_map->set(e, true); }
       
   298 
       
   299     bool hidden(const Node& n) const { return !(*_node_filter_map)[n]; }
       
   300     bool hidden(const Edge& e) const { return !(*_edge_filter_map)[e]; }
       
   301 
       
   302     typedef False NodeNumTag;
       
   303     typedef False EdgeNumTag;
       
   304 
       
   305     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;
       
   306     Arc findArc(const Node& u, const Node& v, 
       
   307 		  const Arc& prev = INVALID) {
       
   308       if (!(*_node_filter_map)[u] || !(*_node_filter_map)[v]) {
       
   309         return INVALID;
       
   310       }
       
   311       Arc arc = Parent::findArc(u, v, prev);
       
   312       while (arc != INVALID && !(*_edge_filter_map)[arc]) {
       
   313         arc = Parent::findArc(u, v, arc);
       
   314       }
       
   315       return arc;
       
   316     }
       
   317     Edge findEdge(const Node& u, const Node& v, 
       
   318 		  const Edge& prev = INVALID) {
       
   319       if (!(*_node_filter_map)[u] || !(*_node_filter_map)[v]) {
       
   320         return INVALID;
       
   321       }
       
   322       Edge edge = Parent::findEdge(u, v, prev);
       
   323       while (edge != INVALID && !(*_edge_filter_map)[edge]) {
       
   324         edge = Parent::findEdge(u, v, edge);
       
   325       }
       
   326       return edge;
       
   327     }
       
   328 
       
   329     template <typename _Value>
       
   330     class NodeMap : public SubMapExtender<Adaptor, 
       
   331         typename Parent::template NodeMap<_Value> > {
       
   332     public:
       
   333       typedef _Value Value;
       
   334       typedef SubMapExtender<Adaptor, typename Parent::
       
   335                              template NodeMap<Value> > MapParent;
       
   336     
       
   337       NodeMap(const Adaptor& adaptor) 
       
   338 	: MapParent(adaptor) {}
       
   339       NodeMap(const Adaptor& adaptor, const Value& value) 
       
   340 	: MapParent(adaptor, value) {}
       
   341 
       
   342     private:
       
   343       NodeMap& operator=(const NodeMap& cmap) {
       
   344 	return operator=<NodeMap>(cmap);
       
   345       }
       
   346     
       
   347       template <typename CMap>
       
   348       NodeMap& operator=(const CMap& cmap) {
       
   349         MapParent::operator=(cmap);
       
   350 	return *this;
       
   351       }
       
   352     };
       
   353 
       
   354     template <typename _Value>
       
   355     class ArcMap : public SubMapExtender<Adaptor, 
       
   356 	typename Parent::template ArcMap<_Value> > {
       
   357     public:
       
   358       typedef _Value Value;
       
   359       typedef SubMapExtender<Adaptor, typename Parent::
       
   360                              template ArcMap<Value> > MapParent;
       
   361     
       
   362       ArcMap(const Adaptor& adaptor) 
       
   363 	: MapParent(adaptor) {}
       
   364       ArcMap(const Adaptor& adaptor, const Value& value) 
       
   365 	: MapParent(adaptor, value) {}
       
   366 
       
   367     private:
       
   368       ArcMap& operator=(const ArcMap& cmap) {
       
   369 	return operator=<ArcMap>(cmap);
       
   370       }
       
   371     
       
   372       template <typename CMap>
       
   373       ArcMap& operator=(const CMap& cmap) {
       
   374         MapParent::operator=(cmap);
       
   375 	return *this;
       
   376       }
       
   377     };
       
   378 
       
   379     template <typename _Value>
       
   380     class EdgeMap : public SubMapExtender<Adaptor, 
       
   381         typename Parent::template EdgeMap<_Value> > {
       
   382     public:
       
   383       typedef _Value Value;
       
   384       typedef SubMapExtender<Adaptor, typename Parent::
       
   385                              template EdgeMap<Value> > MapParent;
       
   386     
       
   387       EdgeMap(const Adaptor& adaptor) 
       
   388 	: MapParent(adaptor) {}
       
   389 
       
   390       EdgeMap(const Adaptor& adaptor, const Value& value) 
       
   391 	: MapParent(adaptor, value) {}
       
   392 
       
   393     private:
       
   394       EdgeMap& operator=(const EdgeMap& cmap) {
       
   395 	return operator=<EdgeMap>(cmap);
       
   396       }
       
   397     
       
   398       template <typename CMap>
       
   399       EdgeMap& operator=(const CMap& cmap) {
       
   400         MapParent::operator=(cmap);
       
   401 	return *this;
       
   402       }
       
   403     };
       
   404 
       
   405   };
       
   406 
       
   407   template <typename _Graph, typename NodeFilterMap, typename EdgeFilterMap>
       
   408   class SubGraphAdaptorBase<_Graph, NodeFilterMap, EdgeFilterMap, false> 
       
   409     : public GraphAdaptorBase<_Graph> {
       
   410   public:
       
   411     typedef _Graph Graph;
       
   412     typedef SubGraphAdaptorBase Adaptor;
       
   413     typedef GraphAdaptorBase<_Graph> Parent;
       
   414   protected:
       
   415     NodeFilterMap* _node_filter_map;
       
   416     EdgeFilterMap* _edge_filter_map;
       
   417     SubGraphAdaptorBase() : Parent(), 
       
   418 			    _node_filter_map(0), _edge_filter_map(0) { }
       
   419 
       
   420     void setNodeFilterMap(NodeFilterMap& node_filter_map) {
       
   421       _node_filter_map=&node_filter_map;
       
   422     }
       
   423     void setEdgeFilterMap(EdgeFilterMap& edge_filter_map) {
       
   424       _edge_filter_map=&edge_filter_map;
       
   425     }
       
   426 
       
   427   public:
       
   428 
       
   429     typedef typename Parent::Node Node;
       
   430     typedef typename Parent::Arc Arc;
       
   431     typedef typename Parent::Edge Edge;
       
   432 
       
   433     void first(Node& i) const { 
       
   434       Parent::first(i); 
       
   435       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i); 
       
   436     }
       
   437 
       
   438     void first(Arc& i) const { 
       
   439       Parent::first(i); 
       
   440       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i); 
       
   441     }
       
   442 
       
   443     void first(Edge& i) const { 
       
   444       Parent::first(i); 
       
   445       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i); 
       
   446     }
       
   447 
       
   448     void firstIn(Arc& i, const Node& n) const { 
       
   449       Parent::firstIn(i, n); 
       
   450       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextIn(i); 
       
   451     }
       
   452 
       
   453     void firstOut(Arc& i, const Node& n) const { 
       
   454       Parent::firstOut(i, n); 
       
   455       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextOut(i); 
       
   456     }
       
   457 
       
   458     void firstInc(Edge& i, bool& d, const Node& n) const { 
       
   459       Parent::firstInc(i, d, n); 
       
   460       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextInc(i, d); 
       
   461     }
       
   462 
       
   463     void next(Node& i) const { 
       
   464       Parent::next(i); 
       
   465       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i); 
       
   466     }
       
   467     void next(Arc& i) const { 
       
   468       Parent::next(i); 
       
   469       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i); 
       
   470     }
       
   471     void next(Edge& i) const { 
       
   472       Parent::next(i); 
       
   473       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i); 
       
   474     }
       
   475     void nextIn(Arc& i) const { 
       
   476       Parent::nextIn(i); 
       
   477       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextIn(i); 
       
   478     }
       
   479 
       
   480     void nextOut(Arc& i) const { 
       
   481       Parent::nextOut(i); 
       
   482       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextOut(i); 
       
   483     }
       
   484     void nextInc(Edge& i, bool& d) const { 
       
   485       Parent::nextInc(i, d); 
       
   486       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextInc(i, d); 
       
   487     }
       
   488 
       
   489     void hide(const Node& n) const { _node_filter_map->set(n, false); }
       
   490     void hide(const Edge& e) const { _edge_filter_map->set(e, false); }
       
   491 
       
   492     void unHide(const Node& n) const { _node_filter_map->set(n, true); }
       
   493     void unHide(const Edge& e) const { _edge_filter_map->set(e, true); }
       
   494 
       
   495     bool hidden(const Node& n) const { return !(*_node_filter_map)[n]; }
       
   496     bool hidden(const Edge& e) const { return !(*_edge_filter_map)[e]; }
       
   497 
       
   498     typedef False NodeNumTag;
       
   499     typedef False EdgeNumTag;
       
   500 
       
   501     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;
       
   502     Arc findArc(const Node& u, const Node& v, 
       
   503 		  const Arc& prev = INVALID) {
       
   504       Arc arc = Parent::findArc(u, v, prev);
       
   505       while (arc != INVALID && !(*_edge_filter_map)[arc]) {
       
   506         arc = Parent::findArc(u, v, arc);
       
   507       }
       
   508       return arc;
       
   509     }
       
   510     Edge findEdge(const Node& u, const Node& v, 
       
   511 		  const Edge& prev = INVALID) {
       
   512       Edge edge = Parent::findEdge(u, v, prev);
       
   513       while (edge != INVALID && !(*_edge_filter_map)[edge]) {
       
   514         edge = Parent::findEdge(u, v, edge);
       
   515       }
       
   516       return edge;
       
   517     }
       
   518 
       
   519     template <typename _Value>
       
   520     class NodeMap : public SubMapExtender<Adaptor, 
       
   521         typename Parent::template NodeMap<_Value> > {
       
   522     public:
       
   523       typedef _Value Value;
       
   524       typedef SubMapExtender<Adaptor, typename Parent::
       
   525                              template NodeMap<Value> > MapParent;
       
   526     
       
   527       NodeMap(const Adaptor& adaptor) 
       
   528 	: MapParent(adaptor) {}
       
   529       NodeMap(const Adaptor& adaptor, const Value& value) 
       
   530 	: MapParent(adaptor, value) {}
       
   531     
       
   532     private:
       
   533       NodeMap& operator=(const NodeMap& cmap) {
       
   534 	return operator=<NodeMap>(cmap);
       
   535       }
       
   536     
       
   537       template <typename CMap>
       
   538       NodeMap& operator=(const CMap& cmap) {
       
   539         MapParent::operator=(cmap);
       
   540 	return *this;
       
   541       }
       
   542     };
       
   543 
       
   544     template <typename _Value>
       
   545     class ArcMap : public SubMapExtender<Adaptor, 
       
   546 	typename Parent::template ArcMap<_Value> > {
       
   547     public:
       
   548       typedef _Value Value;
       
   549       typedef SubMapExtender<Adaptor, typename Parent::
       
   550                              template ArcMap<Value> > MapParent;
       
   551     
       
   552       ArcMap(const Adaptor& adaptor) 
       
   553 	: MapParent(adaptor) {}
       
   554       ArcMap(const Adaptor& adaptor, const Value& value) 
       
   555 	: MapParent(adaptor, value) {}
       
   556 
       
   557     private:
       
   558       ArcMap& operator=(const ArcMap& cmap) {
       
   559 	return operator=<ArcMap>(cmap);
       
   560       }
       
   561     
       
   562       template <typename CMap>
       
   563       ArcMap& operator=(const CMap& cmap) {
       
   564         MapParent::operator=(cmap);
       
   565 	return *this;
       
   566       }
       
   567     };
       
   568 
       
   569     template <typename _Value>
       
   570     class EdgeMap : public SubMapExtender<Adaptor, 
       
   571         typename Parent::template EdgeMap<_Value> > {
       
   572     public:
       
   573       typedef _Value Value;
       
   574       typedef SubMapExtender<Adaptor, typename Parent::
       
   575                              template EdgeMap<Value> > MapParent;
       
   576     
       
   577       EdgeMap(const Adaptor& adaptor) 
       
   578 	: MapParent(adaptor) {}
       
   579 
       
   580       EdgeMap(const Adaptor& adaptor, const _Value& value) 
       
   581 	: MapParent(adaptor, value) {}
       
   582 
       
   583     private:
       
   584       EdgeMap& operator=(const EdgeMap& cmap) {
       
   585 	return operator=<EdgeMap>(cmap);
       
   586       }
       
   587     
       
   588       template <typename CMap>
       
   589       EdgeMap& operator=(const CMap& cmap) {
       
   590         MapParent::operator=(cmap);
       
   591 	return *this;
       
   592       }
       
   593     };
       
   594 
       
   595   };
       
   596 
       
   597   /// \ingroup graph_adaptors
       
   598   ///
       
   599   /// \brief A graph adaptor for hiding nodes and edges from an
       
   600   /// undirected graph.
       
   601   /// 
       
   602   /// SubGraphAdaptor shows the graph with filtered node-set and
       
   603   /// edge-set. If the \c checked parameter is true then it filters
       
   604   /// the edge-set to do not get invalid edges which incident node is
       
   605   /// filtered.
       
   606   /// 
       
   607   /// If the \c checked template parameter is false then we have to
       
   608   /// note that the node-iterator cares only the filter on the
       
   609   /// node-set, and the edge-iterator cares only the filter on the
       
   610   /// edge-set.  This way the edge-map should filter all arcs which
       
   611   /// has filtered end node.
       
   612   template<typename _Graph, typename NodeFilterMap, 
       
   613 	   typename EdgeFilterMap, bool checked = true>
       
   614   class SubGraphAdaptor : 
       
   615     public GraphAdaptorExtender<
       
   616     SubGraphAdaptorBase<_Graph, NodeFilterMap, EdgeFilterMap, checked> > {
       
   617   public:
       
   618     typedef _Graph Graph;
       
   619     typedef GraphAdaptorExtender<
       
   620       SubGraphAdaptorBase<_Graph, NodeFilterMap, EdgeFilterMap> > Parent;
       
   621 
       
   622     typedef typename Parent::Node Node;
       
   623     typedef typename Parent::Edge Edge;
       
   624 
       
   625   protected:
       
   626     SubGraphAdaptor() { }
       
   627   public:
       
   628     
       
   629     /// \brief Constructor
       
   630     ///
       
   631     /// Creates a sub-graph-adaptor for the given graph with
       
   632     /// given node and edge map filters.
       
   633     SubGraphAdaptor(Graph& _graph, NodeFilterMap& node_filter_map, 
       
   634 		    EdgeFilterMap& edge_filter_map) { 
       
   635       setGraph(_graph);
       
   636       setNodeFilterMap(node_filter_map);
       
   637       setEdgeFilterMap(edge_filter_map);
       
   638     }
       
   639 
       
   640     /// \brief Hides the node of the graph
       
   641     ///
       
   642     /// This function hides \c n in the digraph, i.e. the iteration 
       
   643     /// jumps over it. This is done by simply setting the value of \c n  
       
   644     /// to be false in the corresponding node-map.
       
   645     void hide(const Node& n) const { Parent::hide(n); }
       
   646 
       
   647     /// \brief Hides the edge of the graph
       
   648     ///
       
   649     /// This function hides \c e in the digraph, i.e. the iteration 
       
   650     /// jumps over it. This is done by simply setting the value of \c e
       
   651     /// to be false in the corresponding edge-map.
       
   652     void hide(const Edge& e) const { Parent::hide(e); }
       
   653 
       
   654     /// \brief Unhides the node of the graph
       
   655     ///
       
   656     /// The value of \c n is set to be true in the node-map which stores 
       
   657     /// hide information. If \c n was hidden previuosly, then it is shown 
       
   658     /// again
       
   659     void unHide(const Node& n) const { Parent::unHide(n); }
       
   660 
       
   661     /// \brief Unhides the edge of the graph
       
   662     ///
       
   663     /// The value of \c e is set to be true in the edge-map which stores 
       
   664     /// hide information. If \c e was hidden previuosly, then it is shown 
       
   665     /// again
       
   666     void unHide(const Edge& e) const { Parent::unHide(e); }
       
   667 
       
   668     /// \brief Returns true if \c n is hidden.
       
   669     ///
       
   670     /// Returns true if \c n is hidden.
       
   671     ///
       
   672     bool hidden(const Node& n) const { return Parent::hidden(n); }
       
   673 
       
   674     /// \brief Returns true if \c e is hidden.
       
   675     ///
       
   676     /// Returns true if \c e is hidden.
       
   677     ///
       
   678     bool hidden(const Edge& e) const { return Parent::hidden(e); }
       
   679   };
       
   680 
       
   681   /// \brief Just gives back a sub-graph adaptor
       
   682   ///
       
   683   /// Just gives back a sub-graph adaptor
       
   684   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>
       
   685   SubGraphAdaptor<const Graph, NodeFilterMap, ArcFilterMap>
       
   686   subGraphAdaptor(const Graph& graph, 
       
   687                    NodeFilterMap& nfm, ArcFilterMap& efm) {
       
   688     return SubGraphAdaptor<const Graph, NodeFilterMap, ArcFilterMap>
       
   689       (graph, nfm, efm);
       
   690   }
       
   691 
       
   692   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>
       
   693   SubGraphAdaptor<const Graph, const NodeFilterMap, ArcFilterMap>
       
   694   subGraphAdaptor(const Graph& graph, 
       
   695                    NodeFilterMap& nfm, ArcFilterMap& efm) {
       
   696     return SubGraphAdaptor<const Graph, const NodeFilterMap, ArcFilterMap>
       
   697       (graph, nfm, efm);
       
   698   }
       
   699 
       
   700   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>
       
   701   SubGraphAdaptor<const Graph, NodeFilterMap, const ArcFilterMap>
       
   702   subGraphAdaptor(const Graph& graph, 
       
   703                    NodeFilterMap& nfm, ArcFilterMap& efm) {
       
   704     return SubGraphAdaptor<const Graph, NodeFilterMap, const ArcFilterMap>
       
   705       (graph, nfm, efm);
       
   706   }
       
   707 
       
   708   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>
       
   709   SubGraphAdaptor<const Graph, const NodeFilterMap, const ArcFilterMap>
       
   710   subGraphAdaptor(const Graph& graph, 
       
   711                    NodeFilterMap& nfm, ArcFilterMap& efm) {
       
   712     return SubGraphAdaptor<const Graph, const NodeFilterMap, 
       
   713       const ArcFilterMap>(graph, nfm, efm);
       
   714   }
       
   715 
       
   716   /// \ingroup graph_adaptors
       
   717   ///
       
   718   /// \brief An adaptor for hiding nodes from an graph.
       
   719   ///
       
   720   /// An adaptor for hiding nodes from an graph.  This
       
   721   /// adaptor specializes SubGraphAdaptor in the way that only the
       
   722   /// node-set can be filtered. In usual case the checked parameter is
       
   723   /// true, we get the induced subgraph. But if the checked parameter
       
   724   /// is false then we can filter only isolated nodes.
       
   725   template<typename _Graph, typename _NodeFilterMap, bool checked = true>
       
   726   class NodeSubGraphAdaptor : 
       
   727     public SubGraphAdaptor<_Graph, _NodeFilterMap, 
       
   728 			   ConstMap<typename _Graph::Edge, bool>, checked> {
       
   729   public:
       
   730     typedef _Graph Graph;
       
   731     typedef _NodeFilterMap NodeFilterMap;
       
   732     typedef SubGraphAdaptor<Graph, NodeFilterMap, 
       
   733 			    ConstMap<typename Graph::Edge, bool> > Parent;
       
   734 
       
   735     typedef typename Parent::Node Node;
       
   736   protected:
       
   737     ConstMap<typename Graph::Edge, bool> const_true_map;
       
   738 
       
   739     NodeSubGraphAdaptor() : const_true_map(true) {
       
   740       Parent::setEdgeFilterMap(const_true_map);
       
   741     }
       
   742 
       
   743   public:
       
   744 
       
   745     /// \brief Constructor
       
   746     ///
       
   747     /// Creates a node-sub-graph-adaptor for the given graph with
       
   748     /// given node map filters.
       
   749     NodeSubGraphAdaptor(Graph& _graph, NodeFilterMap& node_filter_map) : 
       
   750       Parent(), const_true_map(true) { 
       
   751       Parent::setGraph(_graph);
       
   752       Parent::setNodeFilterMap(node_filter_map);
       
   753       Parent::setEdgeFilterMap(const_true_map);
       
   754     }
       
   755 
       
   756     /// \brief Hides the node of the graph
       
   757     ///
       
   758     /// This function hides \c n in the digraph, i.e. the iteration 
       
   759     /// jumps over it. This is done by simply setting the value of \c n  
       
   760     /// to be false in the corresponding node-map.
       
   761     void hide(const Node& n) const { Parent::hide(n); }
       
   762 
       
   763     /// \brief Unhides the node of the graph
       
   764     ///
       
   765     /// The value of \c n is set to be true in the node-map which stores 
       
   766     /// hide information. If \c n was hidden previuosly, then it is shown 
       
   767     /// again
       
   768     void unHide(const Node& n) const { Parent::unHide(n); }
       
   769 
       
   770     /// \brief Returns true if \c n is hidden.
       
   771     ///
       
   772     /// Returns true if \c n is hidden.
       
   773     ///
       
   774     bool hidden(const Node& n) const { return Parent::hidden(n); }
       
   775 
       
   776   };
       
   777 
       
   778   /// \brief Just gives back a node-sub-graph adaptor
       
   779   ///
       
   780   /// Just gives back a node-sub-graph adaptor
       
   781   template<typename Graph, typename NodeFilterMap>
       
   782   NodeSubGraphAdaptor<const Graph, NodeFilterMap>
       
   783   nodeSubGraphAdaptor(const Graph& graph, NodeFilterMap& nfm) {
       
   784     return NodeSubGraphAdaptor<const Graph, NodeFilterMap>(graph, nfm);
       
   785   }
       
   786 
       
   787   template<typename Graph, typename NodeFilterMap>
       
   788   NodeSubGraphAdaptor<const Graph, const NodeFilterMap>
       
   789   nodeSubGraphAdaptor(const Graph& graph, const NodeFilterMap& nfm) {
       
   790     return NodeSubGraphAdaptor<const Graph, const NodeFilterMap>(graph, nfm);
       
   791   }
       
   792 
       
   793   /// \ingroup graph_adaptors
       
   794   ///
       
   795   /// \brief An adaptor for hiding edges from an graph.
       
   796   ///
       
   797   /// \warning Graph adaptors are in even more experimental state
       
   798   /// than the other parts of the lib. Use them at you own risk.
       
   799   ///
       
   800   /// An adaptor for hiding edges from an graph.
       
   801   /// This adaptor specializes SubGraphAdaptor in the way that
       
   802   /// only the arc-set 
       
   803   /// can be filtered.
       
   804   template<typename _Graph, typename _EdgeFilterMap>
       
   805   class EdgeSubGraphAdaptor : 
       
   806     public SubGraphAdaptor<_Graph, ConstMap<typename _Graph::Node,bool>, 
       
   807                            _EdgeFilterMap, false> {
       
   808   public:
       
   809     typedef _Graph Graph;
       
   810     typedef _EdgeFilterMap EdgeFilterMap;
       
   811     typedef SubGraphAdaptor<Graph, ConstMap<typename Graph::Node,bool>, 
       
   812 			    EdgeFilterMap, false> Parent;
       
   813     typedef typename Parent::Edge Edge;
       
   814   protected:
       
   815     ConstMap<typename Graph::Node, bool> const_true_map;
       
   816 
       
   817     EdgeSubGraphAdaptor() : const_true_map(true) {
       
   818       Parent::setNodeFilterMap(const_true_map);
       
   819     }
       
   820 
       
   821   public:
       
   822 
       
   823     /// \brief Constructor
       
   824     ///
       
   825     /// Creates a edge-sub-graph-adaptor for the given graph with
       
   826     /// given node map filters.
       
   827     EdgeSubGraphAdaptor(Graph& _graph, EdgeFilterMap& edge_filter_map) : 
       
   828       Parent(), const_true_map(true) { 
       
   829       Parent::setGraph(_graph);
       
   830       Parent::setNodeFilterMap(const_true_map);
       
   831       Parent::setEdgeFilterMap(edge_filter_map);
       
   832     }
       
   833 
       
   834     /// \brief Hides the edge of the graph
       
   835     ///
       
   836     /// This function hides \c e in the digraph, i.e. the iteration 
       
   837     /// jumps over it. This is done by simply setting the value of \c e
       
   838     /// to be false in the corresponding edge-map.
       
   839     void hide(const Edge& e) const { Parent::hide(e); }
       
   840 
       
   841     /// \brief Unhides the edge of the graph
       
   842     ///
       
   843     /// The value of \c e is set to be true in the edge-map which stores 
       
   844     /// hide information. If \c e was hidden previuosly, then it is shown 
       
   845     /// again
       
   846     void unHide(const Edge& e) const { Parent::unHide(e); }
       
   847 
       
   848     /// \brief Returns true if \c e is hidden.
       
   849     ///
       
   850     /// Returns true if \c e is hidden.
       
   851     ///
       
   852     bool hidden(const Edge& e) const { return Parent::hidden(e); }
       
   853 
       
   854   };
       
   855 
       
   856   /// \brief Just gives back an edge-sub-graph adaptor
       
   857   ///
       
   858   /// Just gives back an edge-sub-graph adaptor
       
   859   template<typename Graph, typename EdgeFilterMap>
       
   860   EdgeSubGraphAdaptor<const Graph, EdgeFilterMap>
       
   861   edgeSubGraphAdaptor(const Graph& graph, EdgeFilterMap& efm) {
       
   862     return EdgeSubGraphAdaptor<const Graph, EdgeFilterMap>(graph, efm);
       
   863   }
       
   864 
       
   865   template<typename Graph, typename EdgeFilterMap>
       
   866   EdgeSubGraphAdaptor<const Graph, const EdgeFilterMap>
       
   867   edgeSubGraphAdaptor(const Graph& graph, const EdgeFilterMap& efm) {
       
   868     return EdgeSubGraphAdaptor<const Graph, const EdgeFilterMap>(graph, efm);
       
   869   }
       
   870 
       
   871   template <typename _Graph, typename _DirectionMap>
       
   872   class DirGraphAdaptorBase {
       
   873   public:
       
   874     
       
   875     typedef _Graph Graph;
       
   876     typedef _DirectionMap DirectionMap;
       
   877 
       
   878     typedef typename Graph::Node Node;
       
   879     typedef typename Graph::Edge Arc;
       
   880    
       
   881     /// \brief Reverse arc
       
   882     /// 
       
   883     /// It reverse the given arc. It simply negate the direction in the map.
       
   884     void reverseArc(const Arc& arc) {
       
   885       _direction->set(arc, !(*_direction)[arc]);
       
   886     }
       
   887 
       
   888     void first(Node& i) const { _graph->first(i); }
       
   889     void first(Arc& i) const { _graph->first(i); }
       
   890     void firstIn(Arc& i, const Node& n) const {
       
   891       bool d;
       
   892       _graph->firstInc(i, d, n);
       
   893       while (i != INVALID && d == (*_direction)[i]) _graph->nextInc(i, d);
       
   894     }
       
   895     void firstOut(Arc& i, const Node& n ) const { 
       
   896       bool d;
       
   897       _graph->firstInc(i, d, n);
       
   898       while (i != INVALID && d != (*_direction)[i]) _graph->nextInc(i, d);
       
   899     }
       
   900 
       
   901     void next(Node& i) const { _graph->next(i); }
       
   902     void next(Arc& i) const { _graph->next(i); }
       
   903     void nextIn(Arc& i) const {
       
   904       bool d = !(*_direction)[i];
       
   905       _graph->nextInc(i, d);
       
   906       while (i != INVALID && d == (*_direction)[i]) _graph->nextInc(i, d);
       
   907     }
       
   908     void nextOut(Arc& i) const {
       
   909       bool d = (*_direction)[i];
       
   910       _graph->nextInc(i, d);
       
   911       while (i != INVALID && d != (*_direction)[i]) _graph->nextInc(i, d);
       
   912     }
       
   913 
       
   914     Node source(const Arc& e) const { 
       
   915       return (*_direction)[e] ? _graph->u(e) : _graph->v(e); 
       
   916     }
       
   917     Node target(const Arc& e) const { 
       
   918       return (*_direction)[e] ? _graph->v(e) : _graph->u(e); 
       
   919     }
       
   920 
       
   921     typedef NodeNumTagIndicator<Graph> NodeNumTag;
       
   922     int nodeNum() const { return _graph->nodeNum(); }
       
   923     
       
   924     typedef EdgeNumTagIndicator<Graph> EdgeNumTag;
       
   925     int arcNum() const { return _graph->edgeNum(); }
       
   926 
       
   927     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;
       
   928     Arc findArc(const Node& u, const Node& v, 
       
   929 		  const Arc& prev = INVALID) {
       
   930       Arc arc = prev;
       
   931       bool d = arc == INVALID ? true : (*_direction)[arc];
       
   932       if (d) {
       
   933         arc = _graph->findEdge(u, v, arc);
       
   934         while (arc != INVALID && !(*_direction)[arc]) {
       
   935           _graph->findEdge(u, v, arc);
       
   936         }
       
   937         if (arc != INVALID) return arc;
       
   938       }
       
   939       _graph->findEdge(v, u, arc);
       
   940       while (arc != INVALID && (*_direction)[arc]) {
       
   941         _graph->findEdge(u, v, arc);
       
   942       }
       
   943       return arc;
       
   944     }
       
   945   
       
   946     Node addNode() { 
       
   947       return Node(_graph->addNode()); 
       
   948     }
       
   949 
       
   950     Arc addArc(const Node& u, const Node& v) {
       
   951       Arc arc = _graph->addArc(u, v);
       
   952       _direction->set(arc, _graph->source(arc) == u);
       
   953       return arc; 
       
   954     }
       
   955 
       
   956     void erase(const Node& i) { _graph->erase(i); }
       
   957     void erase(const Arc& i) { _graph->erase(i); }
       
   958   
       
   959     void clear() { _graph->clear(); }
       
   960     
       
   961     int id(const Node& v) const { return _graph->id(v); }
       
   962     int id(const Arc& e) const { return _graph->id(e); }
       
   963 
       
   964     Node nodeFromId(int idx) const { return _graph->nodeFromId(idx); }
       
   965     Arc arcFromId(int idx) const { return _graph->edgeFromId(idx); }
       
   966 
       
   967     int maxNodeId() const { return _graph->maxNodeId(); }
       
   968     int maxArcId() const { return _graph->maxEdgeId(); }
       
   969 
       
   970     typedef typename ItemSetTraits<Graph, Node>::ItemNotifier NodeNotifier;
       
   971     NodeNotifier& notifier(Node) const { return _graph->notifier(Node()); } 
       
   972 
       
   973     typedef typename ItemSetTraits<Graph, Arc>::ItemNotifier ArcNotifier;
       
   974     ArcNotifier& notifier(Arc) const { return _graph->notifier(Arc()); } 
       
   975 
       
   976     template <typename _Value>
       
   977     class NodeMap : public _Graph::template NodeMap<_Value> {
       
   978     public:
       
   979 
       
   980       typedef typename _Graph::template NodeMap<_Value> Parent;
       
   981 
       
   982       explicit NodeMap(const DirGraphAdaptorBase& adapter) 
       
   983 	: Parent(*adapter._graph) {}
       
   984 
       
   985       NodeMap(const DirGraphAdaptorBase& adapter, const _Value& value)
       
   986 	: Parent(*adapter._graph, value) {}
       
   987 
       
   988     private:
       
   989       NodeMap& operator=(const NodeMap& cmap) {
       
   990         return operator=<NodeMap>(cmap);
       
   991       }
       
   992 
       
   993       template <typename CMap>
       
   994       NodeMap& operator=(const CMap& cmap) {
       
   995         Parent::operator=(cmap);
       
   996         return *this;
       
   997       }
       
   998 
       
   999     };
       
  1000 
       
  1001     template <typename _Value>
       
  1002     class ArcMap : public _Graph::template EdgeMap<_Value> {
       
  1003     public:
       
  1004 
       
  1005       typedef typename Graph::template EdgeMap<_Value> Parent;
       
  1006 
       
  1007       explicit ArcMap(const DirGraphAdaptorBase& adapter) 
       
  1008 	: Parent(*adapter._graph) { }
       
  1009 
       
  1010       ArcMap(const DirGraphAdaptorBase& adapter, const _Value& value)
       
  1011 	: Parent(*adapter._graph, value) { }
       
  1012 
       
  1013     private:
       
  1014       ArcMap& operator=(const ArcMap& cmap) {
       
  1015         return operator=<ArcMap>(cmap);
       
  1016       }
       
  1017 
       
  1018       template <typename CMap>
       
  1019       ArcMap& operator=(const CMap& cmap) {
       
  1020         Parent::operator=(cmap);
       
  1021         return *this;
       
  1022       }
       
  1023     };
       
  1024 
       
  1025     
       
  1026 
       
  1027   protected:
       
  1028     Graph* _graph;
       
  1029     DirectionMap* _direction;
       
  1030 
       
  1031     void setDirectionMap(DirectionMap& direction) {
       
  1032       _direction = &direction;
       
  1033     }
       
  1034 
       
  1035     void setGraph(Graph& graph) {
       
  1036       _graph = &graph;
       
  1037     }
       
  1038 
       
  1039   };
       
  1040 
       
  1041 
       
  1042   /// \ingroup graph_adaptors
       
  1043   ///
       
  1044   /// \brief A directed graph is made from an graph by an adaptor
       
  1045   ///
       
  1046   /// This adaptor gives a direction for each edge in the undirected
       
  1047   /// graph. The direction of the arcs stored in the
       
  1048   /// DirectionMap. This map is a bool map on the edges. If
       
  1049   /// the edge is mapped to true then the direction of the directed
       
  1050   /// arc will be the same as the default direction of the edge. The
       
  1051   /// arcs can be easily reverted by the \ref
       
  1052   /// DirGraphAdaptorBase::reverseArc "reverseArc()" member in the
       
  1053   /// adaptor.
       
  1054   ///
       
  1055   /// It can be used to solve orientation problems on directed graphs.
       
  1056   /// For example how can we orient an graph to get the minimum
       
  1057   /// number of strongly connected components. If we orient the arcs with
       
  1058   /// the dfs algorithm out from the source then we will get such an 
       
  1059   /// orientation. 
       
  1060   ///
       
  1061   /// We use the \ref DfsVisitor "visitor" interface of the 
       
  1062   /// \ref DfsVisit "dfs" algorithm:
       
  1063   ///\code
       
  1064   /// template <typename DirMap>
       
  1065   /// class OrientVisitor : public DfsVisitor<Graph> {
       
  1066   /// public:
       
  1067   ///
       
  1068   ///   OrientVisitor(const Graph& graph, DirMap& dirMap)
       
  1069   ///     : _graph(graph), _dirMap(dirMap), _processed(graph, false) {}
       
  1070   ///
       
  1071   ///   void discover(const Arc& arc) {
       
  1072   ///     _processed.set(arc, true);
       
  1073   ///     _dirMap.set(arc, _graph.direction(arc));
       
  1074   ///   }
       
  1075   ///
       
  1076   ///   void examine(const Arc& arc) {
       
  1077   ///     if (_processed[arc]) return;
       
  1078   ///     _processed.set(arc, true);
       
  1079   ///     _dirMap.set(arc, _graph.direction(arc));
       
  1080   ///   }  
       
  1081   /// 
       
  1082   /// private:
       
  1083   ///   const Graph& _graph;  
       
  1084   ///   DirMap& _dirMap;
       
  1085   ///   Graph::EdgeMap<bool> _processed;
       
  1086   /// };
       
  1087   ///\endcode
       
  1088   ///
       
  1089   /// And now we can use the orientation:
       
  1090   ///\code
       
  1091   /// Graph::EdgeMap<bool> dmap(graph);
       
  1092   ///
       
  1093   /// typedef OrientVisitor<Graph::EdgeMap<bool> > Visitor;
       
  1094   /// Visitor visitor(graph, dmap);
       
  1095   ///
       
  1096   /// DfsVisit<Graph, Visitor> dfs(graph, visitor);
       
  1097   ///
       
  1098   /// dfs.run();
       
  1099   ///
       
  1100   /// typedef DirGraphAdaptor<Graph> DGraph;
       
  1101   /// DGraph dgraph(graph, dmap);
       
  1102   ///
       
  1103   /// LEMON_ASSERT(countStronglyConnectedComponents(dgraph) == 
       
  1104   ///              countBiArcConnectedComponents(graph), "Wrong Orientation");
       
  1105   ///\endcode
       
  1106   ///
       
  1107   /// The number of the bi-connected components is a lower bound for
       
  1108   /// the number of the strongly connected components in the directed
       
  1109   /// graph because if we contract the bi-connected components to
       
  1110   /// nodes we will get a tree therefore we cannot orient arcs in
       
  1111   /// both direction between bi-connected components. In the other way
       
  1112   /// the algorithm will orient one component to be strongly
       
  1113   /// connected. The two relations proof that the assertion will
       
  1114   /// be always true and the found solution is optimal.
       
  1115   ///
       
  1116   /// \sa DirGraphAdaptorBase
       
  1117   /// \sa dirGraphAdaptor
       
  1118   template<typename _Graph, 
       
  1119            typename DirectionMap = typename _Graph::template EdgeMap<bool> > 
       
  1120   class DirGraphAdaptor : 
       
  1121     public DigraphAdaptorExtender<DirGraphAdaptorBase<_Graph, DirectionMap> > {
       
  1122   public:
       
  1123     typedef _Graph Graph;
       
  1124     typedef DigraphAdaptorExtender<
       
  1125       DirGraphAdaptorBase<_Graph, DirectionMap> > Parent;
       
  1126     typedef typename Parent::Arc Arc;
       
  1127   protected:
       
  1128     DirGraphAdaptor() { }
       
  1129   public:
       
  1130     
       
  1131     /// \brief Constructor of the adaptor
       
  1132     ///
       
  1133     /// Constructor of the adaptor
       
  1134     DirGraphAdaptor(Graph& graph, DirectionMap& direction) { 
       
  1135       setGraph(graph);
       
  1136       setDirectionMap(direction);
       
  1137     }
       
  1138 
       
  1139     /// \brief Reverse arc
       
  1140     /// 
       
  1141     /// It reverse the given arc. It simply negate the direction in the map.
       
  1142     void reverseArc(const Arc& a) {
       
  1143       Parent::reverseArc(a);
       
  1144     }
       
  1145   };
       
  1146 
       
  1147   /// \brief Just gives back a DirGraphAdaptor
       
  1148   ///
       
  1149   /// Just gives back a DirGraphAdaptor
       
  1150   template<typename Graph, typename DirectionMap>
       
  1151   DirGraphAdaptor<const Graph, DirectionMap>
       
  1152   dirGraphAdaptor(const Graph& graph, DirectionMap& dm) {
       
  1153     return DirGraphAdaptor<const Graph, DirectionMap>(graph, dm);
       
  1154   }
       
  1155 
       
  1156   template<typename Graph, typename DirectionMap>
       
  1157   DirGraphAdaptor<const Graph, const DirectionMap>
       
  1158   dirGraphAdaptor(const Graph& graph, const DirectionMap& dm) {
       
  1159     return DirGraphAdaptor<const Graph, const DirectionMap>(graph, dm);
       
  1160   }
       
  1161 
       
  1162 }
       
  1163 
       
  1164 #endif