lemon/adaptors.h
author Balazs Dezso <deba@inf.elte.hu>
Wed, 03 Dec 2008 14:23:22 +0100
changeset 419 9afe81e4c543
parent 415 4b6112235fad
child 440 88ed40ad0d4f
child 446 d369e885d196
permissions -rw-r--r--
Renamings in connectivity.h and bug fix in DfsVisit (#61)

- The include guard, the private namespace and some local varibles
are renamed
- The stop() must be called in DfsVisit, if there are not outgoing
arcs from the added node
     1 /* -*- mode: C++; indent-tabs-mode: nil; -*-
     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_ADAPTORS_H
    20 #define LEMON_ADAPTORS_H
    21 
    22 /// \ingroup graph_adaptors
    23 /// \file
    24 /// \brief Several graph adaptors
    25 ///
    26 /// This file contains several useful adaptors for digraphs and graphs.
    27 
    28 #include <lemon/core.h>
    29 #include <lemon/maps.h>
    30 #include <lemon/bits/variant.h>
    31 
    32 #include <lemon/bits/graph_adaptor_extender.h>
    33 #include <lemon/tolerance.h>
    34 
    35 #include <algorithm>
    36 
    37 namespace lemon {
    38 
    39   template<typename _Digraph>
    40   class DigraphAdaptorBase {
    41   public:
    42     typedef _Digraph Digraph;
    43     typedef DigraphAdaptorBase Adaptor;
    44     typedef Digraph ParentDigraph;
    45 
    46   protected:
    47     Digraph* _digraph;
    48     DigraphAdaptorBase() : _digraph(0) { }
    49     void setDigraph(Digraph& digraph) { _digraph = &digraph; }
    50 
    51   public:
    52     DigraphAdaptorBase(Digraph& digraph) : _digraph(&digraph) { }
    53 
    54     typedef typename Digraph::Node Node;
    55     typedef typename Digraph::Arc Arc;
    56 
    57     void first(Node& i) const { _digraph->first(i); }
    58     void first(Arc& i) const { _digraph->first(i); }
    59     void firstIn(Arc& i, const Node& n) const { _digraph->firstIn(i, n); }
    60     void firstOut(Arc& i, const Node& n ) const { _digraph->firstOut(i, n); }
    61 
    62     void next(Node& i) const { _digraph->next(i); }
    63     void next(Arc& i) const { _digraph->next(i); }
    64     void nextIn(Arc& i) const { _digraph->nextIn(i); }
    65     void nextOut(Arc& i) const { _digraph->nextOut(i); }
    66 
    67     Node source(const Arc& a) const { return _digraph->source(a); }
    68     Node target(const Arc& a) const { return _digraph->target(a); }
    69 
    70     typedef NodeNumTagIndicator<Digraph> NodeNumTag;
    71     int nodeNum() const { return _digraph->nodeNum(); }
    72 
    73     typedef EdgeNumTagIndicator<Digraph> EdgeNumTag;
    74     int arcNum() const { return _digraph->arcNum(); }
    75 
    76     typedef FindEdgeTagIndicator<Digraph> FindEdgeTag;
    77     Arc findArc(const Node& u, const Node& v, const Arc& prev = INVALID) {
    78       return _digraph->findArc(u, v, prev);
    79     }
    80 
    81     Node addNode() { return _digraph->addNode(); }
    82     Arc addArc(const Node& u, const Node& v) { return _digraph->addArc(u, v); }
    83 
    84     void erase(const Node& n) const { _digraph->erase(n); }
    85     void erase(const Arc& a) const { _digraph->erase(a); }
    86 
    87     void clear() const { _digraph->clear(); }
    88 
    89     int id(const Node& n) const { return _digraph->id(n); }
    90     int id(const Arc& a) const { return _digraph->id(a); }
    91 
    92     Node nodeFromId(int ix) const { return _digraph->nodeFromId(ix); }
    93     Arc arcFromId(int ix) const { return _digraph->arcFromId(ix); }
    94 
    95     int maxNodeId() const { return _digraph->maxNodeId(); }
    96     int maxArcId() const { return _digraph->maxArcId(); }
    97 
    98     typedef typename ItemSetTraits<Digraph, Node>::ItemNotifier NodeNotifier;
    99     NodeNotifier& notifier(Node) const { return _digraph->notifier(Node()); }
   100 
   101     typedef typename ItemSetTraits<Digraph, Arc>::ItemNotifier ArcNotifier;
   102     ArcNotifier& notifier(Arc) const { return _digraph->notifier(Arc()); }
   103 
   104     template <typename _Value>
   105     class NodeMap : public Digraph::template NodeMap<_Value> {
   106     public:
   107 
   108       typedef typename Digraph::template NodeMap<_Value> Parent;
   109 
   110       explicit NodeMap(const Adaptor& adaptor)
   111         : Parent(*adaptor._digraph) {}
   112 
   113       NodeMap(const Adaptor& adaptor, const _Value& value)
   114         : Parent(*adaptor._digraph, value) { }
   115 
   116     private:
   117       NodeMap& operator=(const NodeMap& cmap) {
   118         return operator=<NodeMap>(cmap);
   119       }
   120 
   121       template <typename CMap>
   122       NodeMap& operator=(const CMap& cmap) {
   123         Parent::operator=(cmap);
   124         return *this;
   125       }
   126 
   127     };
   128 
   129     template <typename _Value>
   130     class ArcMap : public Digraph::template ArcMap<_Value> {
   131     public:
   132 
   133       typedef typename Digraph::template ArcMap<_Value> Parent;
   134 
   135       explicit ArcMap(const Adaptor& adaptor)
   136         : Parent(*adaptor._digraph) {}
   137 
   138       ArcMap(const Adaptor& adaptor, const _Value& value)
   139         : Parent(*adaptor._digraph, value) {}
   140 
   141     private:
   142       ArcMap& operator=(const ArcMap& cmap) {
   143         return operator=<ArcMap>(cmap);
   144       }
   145 
   146       template <typename CMap>
   147       ArcMap& operator=(const CMap& cmap) {
   148         Parent::operator=(cmap);
   149         return *this;
   150       }
   151 
   152     };
   153 
   154   };
   155 
   156   template<typename _Graph>
   157   class GraphAdaptorBase {
   158   public:
   159     typedef _Graph Graph;
   160     typedef Graph ParentGraph;
   161 
   162   protected:
   163     Graph* _graph;
   164 
   165     GraphAdaptorBase() : _graph(0) {}
   166 
   167     void setGraph(Graph& graph) { _graph = &graph; }
   168 
   169   public:
   170     GraphAdaptorBase(Graph& graph) : _graph(&graph) {}
   171 
   172     typedef typename Graph::Node Node;
   173     typedef typename Graph::Arc Arc;
   174     typedef typename Graph::Edge Edge;
   175 
   176     void first(Node& i) const { _graph->first(i); }
   177     void first(Arc& i) const { _graph->first(i); }
   178     void first(Edge& i) const { _graph->first(i); }
   179     void firstIn(Arc& i, const Node& n) const { _graph->firstIn(i, n); }
   180     void firstOut(Arc& i, const Node& n ) const { _graph->firstOut(i, n); }
   181     void firstInc(Edge &i, bool &d, const Node &n) const {
   182       _graph->firstInc(i, d, n);
   183     }
   184 
   185     void next(Node& i) const { _graph->next(i); }
   186     void next(Arc& i) const { _graph->next(i); }
   187     void next(Edge& i) const { _graph->next(i); }
   188     void nextIn(Arc& i) const { _graph->nextIn(i); }
   189     void nextOut(Arc& i) const { _graph->nextOut(i); }
   190     void nextInc(Edge &i, bool &d) const { _graph->nextInc(i, d); }
   191 
   192     Node u(const Edge& e) const { return _graph->u(e); }
   193     Node v(const Edge& e) const { return _graph->v(e); }
   194 
   195     Node source(const Arc& a) const { return _graph->source(a); }
   196     Node target(const Arc& a) const { return _graph->target(a); }
   197 
   198     typedef NodeNumTagIndicator<Graph> NodeNumTag;
   199     int nodeNum() const { return _graph->nodeNum(); }
   200 
   201     typedef EdgeNumTagIndicator<Graph> EdgeNumTag;
   202     int arcNum() const { return _graph->arcNum(); }
   203     int edgeNum() const { return _graph->edgeNum(); }
   204 
   205     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;
   206     Arc findArc(const Node& u, const Node& v, const Arc& prev = INVALID) {
   207       return _graph->findArc(u, v, prev);
   208     }
   209     Edge findEdge(const Node& u, const Node& v, const Edge& prev = INVALID) {
   210       return _graph->findEdge(u, v, prev);
   211     }
   212 
   213     Node addNode() { return _graph->addNode(); }
   214     Edge addEdge(const Node& u, const Node& v) { return _graph->addEdge(u, v); }
   215 
   216     void erase(const Node& i) { _graph->erase(i); }
   217     void erase(const Edge& i) { _graph->erase(i); }
   218 
   219     void clear() { _graph->clear(); }
   220 
   221     bool direction(const Arc& a) const { return _graph->direction(a); }
   222     Arc direct(const Edge& e, bool d) const { return _graph->direct(e, d); }
   223 
   224     int id(const Node& v) const { return _graph->id(v); }
   225     int id(const Arc& a) const { return _graph->id(a); }
   226     int id(const Edge& e) const { return _graph->id(e); }
   227 
   228     Node nodeFromId(int ix) const { return _graph->nodeFromId(ix); }
   229     Arc arcFromId(int ix) const { return _graph->arcFromId(ix); }
   230     Edge edgeFromId(int ix) const { return _graph->edgeFromId(ix); }
   231 
   232     int maxNodeId() const { return _graph->maxNodeId(); }
   233     int maxArcId() const { return _graph->maxArcId(); }
   234     int maxEdgeId() const { return _graph->maxEdgeId(); }
   235 
   236     typedef typename ItemSetTraits<Graph, Node>::ItemNotifier NodeNotifier;
   237     NodeNotifier& notifier(Node) const { return _graph->notifier(Node()); }
   238 
   239     typedef typename ItemSetTraits<Graph, Arc>::ItemNotifier ArcNotifier;
   240     ArcNotifier& notifier(Arc) const { return _graph->notifier(Arc()); }
   241 
   242     typedef typename ItemSetTraits<Graph, Edge>::ItemNotifier EdgeNotifier;
   243     EdgeNotifier& notifier(Edge) const { return _graph->notifier(Edge()); }
   244 
   245     template <typename _Value>
   246     class NodeMap : public Graph::template NodeMap<_Value> {
   247     public:
   248       typedef typename Graph::template NodeMap<_Value> Parent;
   249       explicit NodeMap(const GraphAdaptorBase<Graph>& adapter)
   250         : Parent(*adapter._graph) {}
   251       NodeMap(const GraphAdaptorBase<Graph>& adapter, const _Value& value)
   252         : Parent(*adapter._graph, value) {}
   253 
   254     private:
   255       NodeMap& operator=(const NodeMap& cmap) {
   256         return operator=<NodeMap>(cmap);
   257       }
   258 
   259       template <typename CMap>
   260       NodeMap& operator=(const CMap& cmap) {
   261         Parent::operator=(cmap);
   262         return *this;
   263       }
   264 
   265     };
   266 
   267     template <typename _Value>
   268     class ArcMap : public Graph::template ArcMap<_Value> {
   269     public:
   270       typedef typename Graph::template ArcMap<_Value> Parent;
   271       explicit ArcMap(const GraphAdaptorBase<Graph>& adapter)
   272         : Parent(*adapter._graph) {}
   273       ArcMap(const GraphAdaptorBase<Graph>& adapter, const _Value& value)
   274         : Parent(*adapter._graph, value) {}
   275 
   276     private:
   277       ArcMap& operator=(const ArcMap& cmap) {
   278         return operator=<ArcMap>(cmap);
   279       }
   280 
   281       template <typename CMap>
   282       ArcMap& operator=(const CMap& cmap) {
   283         Parent::operator=(cmap);
   284         return *this;
   285       }
   286     };
   287 
   288     template <typename _Value>
   289     class EdgeMap : public Graph::template EdgeMap<_Value> {
   290     public:
   291       typedef typename Graph::template EdgeMap<_Value> Parent;
   292       explicit EdgeMap(const GraphAdaptorBase<Graph>& adapter)
   293         : Parent(*adapter._graph) {}
   294       EdgeMap(const GraphAdaptorBase<Graph>& adapter, const _Value& value)
   295         : Parent(*adapter._graph, value) {}
   296 
   297     private:
   298       EdgeMap& operator=(const EdgeMap& cmap) {
   299         return operator=<EdgeMap>(cmap);
   300       }
   301 
   302       template <typename CMap>
   303       EdgeMap& operator=(const CMap& cmap) {
   304         Parent::operator=(cmap);
   305         return *this;
   306       }
   307     };
   308 
   309   };
   310 
   311   template <typename _Digraph>
   312   class ReverseDigraphBase : public DigraphAdaptorBase<_Digraph> {
   313   public:
   314     typedef _Digraph Digraph;
   315     typedef DigraphAdaptorBase<_Digraph> Parent;
   316   protected:
   317     ReverseDigraphBase() : Parent() { }
   318   public:
   319     typedef typename Parent::Node Node;
   320     typedef typename Parent::Arc Arc;
   321 
   322     void firstIn(Arc& a, const Node& n) const { Parent::firstOut(a, n); }
   323     void firstOut(Arc& a, const Node& n ) const { Parent::firstIn(a, n); }
   324 
   325     void nextIn(Arc& a) const { Parent::nextOut(a); }
   326     void nextOut(Arc& a) const { Parent::nextIn(a); }
   327 
   328     Node source(const Arc& a) const { return Parent::target(a); }
   329     Node target(const Arc& a) const { return Parent::source(a); }
   330 
   331     Arc addArc(const Node& u, const Node& v) { return Parent::addArc(v, u); }
   332 
   333     typedef FindEdgeTagIndicator<Digraph> FindEdgeTag;
   334     Arc findArc(const Node& u, const Node& v,
   335                 const Arc& prev = INVALID) {
   336       return Parent::findArc(v, u, prev);
   337     }
   338 
   339   };
   340 
   341   /// \ingroup graph_adaptors
   342   ///
   343   /// \brief A digraph adaptor which reverses the orientation of the arcs.
   344   ///
   345   /// ReverseDigraph reverses the arcs in the adapted digraph. The
   346   /// SubDigraph is conform to the \ref concepts::Digraph
   347   /// "Digraph concept".
   348   ///
   349   /// \tparam _Digraph It must be conform to the \ref concepts::Digraph
   350   /// "Digraph concept". The type can be specified to be const.
   351   template<typename _Digraph>
   352   class ReverseDigraph :
   353     public DigraphAdaptorExtender<ReverseDigraphBase<_Digraph> > {
   354   public:
   355     typedef _Digraph Digraph;
   356     typedef DigraphAdaptorExtender<
   357       ReverseDigraphBase<_Digraph> > Parent;
   358   protected:
   359     ReverseDigraph() { }
   360   public:
   361 
   362     /// \brief Constructor
   363     ///
   364     /// Creates a reverse digraph adaptor for the given digraph
   365     explicit ReverseDigraph(Digraph& digraph) {
   366       Parent::setDigraph(digraph);
   367     }
   368   };
   369 
   370   /// \brief Just gives back a reverse digraph adaptor
   371   ///
   372   /// Just gives back a reverse digraph adaptor
   373   template<typename Digraph>
   374   ReverseDigraph<const Digraph> reverseDigraph(const Digraph& digraph) {
   375     return ReverseDigraph<const Digraph>(digraph);
   376   }
   377 
   378   template <typename _Digraph, typename _NodeFilterMap,
   379             typename _ArcFilterMap, bool _checked = true>
   380   class SubDigraphBase : public DigraphAdaptorBase<_Digraph> {
   381   public:
   382     typedef _Digraph Digraph;
   383     typedef _NodeFilterMap NodeFilterMap;
   384     typedef _ArcFilterMap ArcFilterMap;
   385 
   386     typedef SubDigraphBase Adaptor;
   387     typedef DigraphAdaptorBase<_Digraph> Parent;
   388   protected:
   389     NodeFilterMap* _node_filter;
   390     ArcFilterMap* _arc_filter;
   391     SubDigraphBase()
   392       : Parent(), _node_filter(0), _arc_filter(0) { }
   393 
   394     void setNodeFilterMap(NodeFilterMap& node_filter) {
   395       _node_filter = &node_filter;
   396     }
   397     void setArcFilterMap(ArcFilterMap& arc_filter) {
   398       _arc_filter = &arc_filter;
   399     }
   400 
   401   public:
   402 
   403     typedef typename Parent::Node Node;
   404     typedef typename Parent::Arc Arc;
   405 
   406     void first(Node& i) const {
   407       Parent::first(i);
   408       while (i != INVALID && !(*_node_filter)[i]) Parent::next(i);
   409     }
   410 
   411     void first(Arc& i) const {
   412       Parent::first(i);
   413       while (i != INVALID && (!(*_arc_filter)[i]
   414                               || !(*_node_filter)[Parent::source(i)]
   415                               || !(*_node_filter)[Parent::target(i)]))
   416         Parent::next(i);
   417     }
   418 
   419     void firstIn(Arc& i, const Node& n) const {
   420       Parent::firstIn(i, n);
   421       while (i != INVALID && (!(*_arc_filter)[i]
   422                               || !(*_node_filter)[Parent::source(i)]))
   423         Parent::nextIn(i);
   424     }
   425 
   426     void firstOut(Arc& i, const Node& n) const {
   427       Parent::firstOut(i, n);
   428       while (i != INVALID && (!(*_arc_filter)[i]
   429                               || !(*_node_filter)[Parent::target(i)]))
   430         Parent::nextOut(i);
   431     }
   432 
   433     void next(Node& i) const {
   434       Parent::next(i);
   435       while (i != INVALID && !(*_node_filter)[i]) Parent::next(i);
   436     }
   437 
   438     void next(Arc& i) const {
   439       Parent::next(i);
   440       while (i != INVALID && (!(*_arc_filter)[i]
   441                               || !(*_node_filter)[Parent::source(i)]
   442                               || !(*_node_filter)[Parent::target(i)]))
   443         Parent::next(i);
   444     }
   445 
   446     void nextIn(Arc& i) const {
   447       Parent::nextIn(i);
   448       while (i != INVALID && (!(*_arc_filter)[i]
   449                               || !(*_node_filter)[Parent::source(i)]))
   450         Parent::nextIn(i);
   451     }
   452 
   453     void nextOut(Arc& i) const {
   454       Parent::nextOut(i);
   455       while (i != INVALID && (!(*_arc_filter)[i]
   456                               || !(*_node_filter)[Parent::target(i)]))
   457         Parent::nextOut(i);
   458     }
   459 
   460     void hide(const Node& n) const { _node_filter->set(n, false); }
   461     void hide(const Arc& a) const { _arc_filter->set(a, false); }
   462 
   463     void unHide(const Node& n) const { _node_filter->set(n, true); }
   464     void unHide(const Arc& a) const { _arc_filter->set(a, true); }
   465 
   466     bool hidden(const Node& n) const { return !(*_node_filter)[n]; }
   467     bool hidden(const Arc& a) const { return !(*_arc_filter)[a]; }
   468 
   469     typedef False NodeNumTag;
   470     typedef False EdgeNumTag;
   471 
   472     typedef FindEdgeTagIndicator<Digraph> FindEdgeTag;
   473     Arc findArc(const Node& source, const Node& target,
   474                 const Arc& prev = INVALID) {
   475       if (!(*_node_filter)[source] || !(*_node_filter)[target]) {
   476         return INVALID;
   477       }
   478       Arc arc = Parent::findArc(source, target, prev);
   479       while (arc != INVALID && !(*_arc_filter)[arc]) {
   480         arc = Parent::findArc(source, target, arc);
   481       }
   482       return arc;
   483     }
   484 
   485     template <typename _Value>
   486     class NodeMap : public SubMapExtender<Adaptor,
   487       typename Parent::template NodeMap<_Value> > {
   488     public:
   489       typedef _Value Value;
   490       typedef SubMapExtender<Adaptor, typename Parent::
   491                              template NodeMap<Value> > MapParent;
   492 
   493       NodeMap(const Adaptor& adaptor)
   494         : MapParent(adaptor) {}
   495       NodeMap(const Adaptor& adaptor, const Value& value)
   496         : MapParent(adaptor, value) {}
   497 
   498     private:
   499       NodeMap& operator=(const NodeMap& cmap) {
   500         return operator=<NodeMap>(cmap);
   501       }
   502 
   503       template <typename CMap>
   504       NodeMap& operator=(const CMap& cmap) {
   505         MapParent::operator=(cmap);
   506         return *this;
   507       }
   508     };
   509 
   510     template <typename _Value>
   511     class ArcMap : public SubMapExtender<Adaptor,
   512       typename Parent::template ArcMap<_Value> > {
   513     public:
   514       typedef _Value Value;
   515       typedef SubMapExtender<Adaptor, typename Parent::
   516                              template ArcMap<Value> > MapParent;
   517 
   518       ArcMap(const Adaptor& adaptor)
   519         : MapParent(adaptor) {}
   520       ArcMap(const Adaptor& adaptor, const Value& value)
   521         : MapParent(adaptor, value) {}
   522 
   523     private:
   524       ArcMap& operator=(const ArcMap& cmap) {
   525         return operator=<ArcMap>(cmap);
   526       }
   527 
   528       template <typename CMap>
   529       ArcMap& operator=(const CMap& cmap) {
   530         MapParent::operator=(cmap);
   531         return *this;
   532       }
   533     };
   534 
   535   };
   536 
   537   template <typename _Digraph, typename _NodeFilterMap, typename _ArcFilterMap>
   538   class SubDigraphBase<_Digraph, _NodeFilterMap, _ArcFilterMap, false>
   539     : public DigraphAdaptorBase<_Digraph> {
   540   public:
   541     typedef _Digraph Digraph;
   542     typedef _NodeFilterMap NodeFilterMap;
   543     typedef _ArcFilterMap ArcFilterMap;
   544 
   545     typedef SubDigraphBase Adaptor;
   546     typedef DigraphAdaptorBase<Digraph> Parent;
   547   protected:
   548     NodeFilterMap* _node_filter;
   549     ArcFilterMap* _arc_filter;
   550     SubDigraphBase()
   551       : Parent(), _node_filter(0), _arc_filter(0) { }
   552 
   553     void setNodeFilterMap(NodeFilterMap& node_filter) {
   554       _node_filter = &node_filter;
   555     }
   556     void setArcFilterMap(ArcFilterMap& arc_filter) {
   557       _arc_filter = &arc_filter;
   558     }
   559 
   560   public:
   561 
   562     typedef typename Parent::Node Node;
   563     typedef typename Parent::Arc Arc;
   564 
   565     void first(Node& i) const {
   566       Parent::first(i);
   567       while (i!=INVALID && !(*_node_filter)[i]) Parent::next(i);
   568     }
   569 
   570     void first(Arc& i) const {
   571       Parent::first(i);
   572       while (i!=INVALID && !(*_arc_filter)[i]) Parent::next(i);
   573     }
   574 
   575     void firstIn(Arc& i, const Node& n) const {
   576       Parent::firstIn(i, n);
   577       while (i!=INVALID && !(*_arc_filter)[i]) Parent::nextIn(i);
   578     }
   579 
   580     void firstOut(Arc& i, const Node& n) const {
   581       Parent::firstOut(i, n);
   582       while (i!=INVALID && !(*_arc_filter)[i]) Parent::nextOut(i);
   583     }
   584 
   585     void next(Node& i) const {
   586       Parent::next(i);
   587       while (i!=INVALID && !(*_node_filter)[i]) Parent::next(i);
   588     }
   589     void next(Arc& i) const {
   590       Parent::next(i);
   591       while (i!=INVALID && !(*_arc_filter)[i]) Parent::next(i);
   592     }
   593     void nextIn(Arc& i) const {
   594       Parent::nextIn(i);
   595       while (i!=INVALID && !(*_arc_filter)[i]) Parent::nextIn(i);
   596     }
   597 
   598     void nextOut(Arc& i) const {
   599       Parent::nextOut(i);
   600       while (i!=INVALID && !(*_arc_filter)[i]) Parent::nextOut(i);
   601     }
   602 
   603     void hide(const Node& n) const { _node_filter->set(n, false); }
   604     void hide(const Arc& e) const { _arc_filter->set(e, false); }
   605 
   606     void unHide(const Node& n) const { _node_filter->set(n, true); }
   607     void unHide(const Arc& e) const { _arc_filter->set(e, true); }
   608 
   609     bool hidden(const Node& n) const { return !(*_node_filter)[n]; }
   610     bool hidden(const Arc& e) const { return !(*_arc_filter)[e]; }
   611 
   612     typedef False NodeNumTag;
   613     typedef False EdgeNumTag;
   614 
   615     typedef FindEdgeTagIndicator<Digraph> FindEdgeTag;
   616     Arc findArc(const Node& source, const Node& target,
   617                 const Arc& prev = INVALID) {
   618       if (!(*_node_filter)[source] || !(*_node_filter)[target]) {
   619         return INVALID;
   620       }
   621       Arc arc = Parent::findArc(source, target, prev);
   622       while (arc != INVALID && !(*_arc_filter)[arc]) {
   623         arc = Parent::findArc(source, target, arc);
   624       }
   625       return arc;
   626     }
   627 
   628     template <typename _Value>
   629     class NodeMap : public SubMapExtender<Adaptor,
   630       typename Parent::template NodeMap<_Value> > {
   631     public:
   632       typedef _Value Value;
   633       typedef SubMapExtender<Adaptor, typename Parent::
   634                              template NodeMap<Value> > MapParent;
   635 
   636       NodeMap(const Adaptor& adaptor)
   637         : MapParent(adaptor) {}
   638       NodeMap(const Adaptor& adaptor, const Value& value)
   639         : MapParent(adaptor, value) {}
   640 
   641     private:
   642       NodeMap& operator=(const NodeMap& cmap) {
   643         return operator=<NodeMap>(cmap);
   644       }
   645 
   646       template <typename CMap>
   647       NodeMap& operator=(const CMap& cmap) {
   648         MapParent::operator=(cmap);
   649         return *this;
   650       }
   651     };
   652 
   653     template <typename _Value>
   654     class ArcMap : public SubMapExtender<Adaptor,
   655       typename Parent::template ArcMap<_Value> > {
   656     public:
   657       typedef _Value Value;
   658       typedef SubMapExtender<Adaptor, typename Parent::
   659                              template ArcMap<Value> > MapParent;
   660 
   661       ArcMap(const Adaptor& adaptor)
   662         : MapParent(adaptor) {}
   663       ArcMap(const Adaptor& adaptor, const Value& value)
   664         : MapParent(adaptor, value) {}
   665 
   666     private:
   667       ArcMap& operator=(const ArcMap& cmap) {
   668         return operator=<ArcMap>(cmap);
   669       }
   670 
   671       template <typename CMap>
   672       ArcMap& operator=(const CMap& cmap) {
   673         MapParent::operator=(cmap);
   674         return *this;
   675       }
   676     };
   677 
   678   };
   679 
   680   /// \ingroup graph_adaptors
   681   ///
   682   /// \brief An adaptor for hiding nodes and arcs in a digraph
   683   ///
   684   /// SubDigraph hides nodes and arcs in a digraph. A bool node map
   685   /// and a bool arc map must be specified, which define the filters
   686   /// for nodes and arcs. Just the nodes and arcs with true value are
   687   /// shown in the subdigraph. The SubDigraph is conform to the \ref
   688   /// concepts::Digraph "Digraph concept". If the \c _checked parameter
   689   /// is true, then the arcs incident to filtered nodes are also
   690   /// filtered out.
   691   ///
   692   /// \tparam _Digraph It must be conform to the \ref
   693   /// concepts::Digraph "Digraph concept". The type can be specified
   694   /// to const.
   695   /// \tparam _NodeFilterMap A bool valued node map of the the adapted digraph.
   696   /// \tparam _ArcFilterMap A bool valued arc map of the the adapted digraph.
   697   /// \tparam _checked If the parameter is false then the arc filtering
   698   /// is not checked with respect to node filter. Otherwise, each arc
   699   /// is automatically filtered, which is incident to a filtered node.
   700   ///
   701   /// \see FilterNodes
   702   /// \see FilterArcs
   703   template<typename _Digraph,
   704            typename _NodeFilterMap = typename _Digraph::template NodeMap<bool>,
   705            typename _ArcFilterMap = typename _Digraph::template ArcMap<bool>,
   706            bool _checked = true>
   707   class SubDigraph
   708     : public DigraphAdaptorExtender<
   709       SubDigraphBase<_Digraph, _NodeFilterMap, _ArcFilterMap, _checked> > {
   710   public:
   711     typedef _Digraph Digraph;
   712     typedef _NodeFilterMap NodeFilterMap;
   713     typedef _ArcFilterMap ArcFilterMap;
   714 
   715     typedef DigraphAdaptorExtender<
   716       SubDigraphBase<Digraph, NodeFilterMap, ArcFilterMap, _checked> >
   717     Parent;
   718 
   719     typedef typename Parent::Node Node;
   720     typedef typename Parent::Arc Arc;
   721 
   722   protected:
   723     SubDigraph() { }
   724   public:
   725 
   726     /// \brief Constructor
   727     ///
   728     /// Creates a subdigraph for the given digraph with
   729     /// given node and arc map filters.
   730     SubDigraph(Digraph& digraph, NodeFilterMap& node_filter,
   731                ArcFilterMap& arc_filter) {
   732       setDigraph(digraph);
   733       setNodeFilterMap(node_filter);
   734       setArcFilterMap(arc_filter);
   735     }
   736 
   737     /// \brief Hides the node of the graph
   738     ///
   739     /// This function hides \c n in the digraph, i.e. the iteration
   740     /// jumps over it. This is done by simply setting the value of \c n
   741     /// to be false in the corresponding node-map.
   742     void hide(const Node& n) const { Parent::hide(n); }
   743 
   744     /// \brief Hides the arc of the graph
   745     ///
   746     /// This function hides \c a in the digraph, i.e. the iteration
   747     /// jumps over it. This is done by simply setting the value of \c a
   748     /// to be false in the corresponding arc-map.
   749     void hide(const Arc& a) const { Parent::hide(a); }
   750 
   751     /// \brief Unhides the node of the graph
   752     ///
   753     /// The value of \c n is set to be true in the node-map which stores
   754     /// hide information. If \c n was hidden previuosly, then it is shown
   755     /// again
   756     void unHide(const Node& n) const { Parent::unHide(n); }
   757 
   758     /// \brief Unhides the arc of the graph
   759     ///
   760     /// The value of \c a is set to be true in the arc-map which stores
   761     /// hide information. If \c a was hidden previuosly, then it is shown
   762     /// again
   763     void unHide(const Arc& a) const { Parent::unHide(a); }
   764 
   765     /// \brief Returns true if \c n is hidden.
   766     ///
   767     /// Returns true if \c n is hidden.
   768     ///
   769     bool hidden(const Node& n) const { return Parent::hidden(n); }
   770 
   771     /// \brief Returns true if \c a is hidden.
   772     ///
   773     /// Returns true if \c a is hidden.
   774     ///
   775     bool hidden(const Arc& a) const { return Parent::hidden(a); }
   776 
   777   };
   778 
   779   /// \brief Just gives back a subdigraph
   780   ///
   781   /// Just gives back a subdigraph
   782   template<typename Digraph, typename NodeFilterMap, typename ArcFilterMap>
   783   SubDigraph<const Digraph, NodeFilterMap, ArcFilterMap>
   784   subDigraph(const Digraph& digraph, NodeFilterMap& nfm, ArcFilterMap& afm) {
   785     return SubDigraph<const Digraph, NodeFilterMap, ArcFilterMap>
   786       (digraph, nfm, afm);
   787   }
   788 
   789   template<typename Digraph, typename NodeFilterMap, typename ArcFilterMap>
   790   SubDigraph<const Digraph, const NodeFilterMap, ArcFilterMap>
   791   subDigraph(const Digraph& digraph,
   792              const NodeFilterMap& nfm, ArcFilterMap& afm) {
   793     return SubDigraph<const Digraph, const NodeFilterMap, ArcFilterMap>
   794       (digraph, nfm, afm);
   795   }
   796 
   797   template<typename Digraph, typename NodeFilterMap, typename ArcFilterMap>
   798   SubDigraph<const Digraph, NodeFilterMap, const ArcFilterMap>
   799   subDigraph(const Digraph& digraph,
   800              NodeFilterMap& nfm, const ArcFilterMap& afm) {
   801     return SubDigraph<const Digraph, NodeFilterMap, const ArcFilterMap>
   802       (digraph, nfm, afm);
   803   }
   804 
   805   template<typename Digraph, typename NodeFilterMap, typename ArcFilterMap>
   806   SubDigraph<const Digraph, const NodeFilterMap, const ArcFilterMap>
   807   subDigraph(const Digraph& digraph,
   808              const NodeFilterMap& nfm, const ArcFilterMap& afm) {
   809     return SubDigraph<const Digraph, const NodeFilterMap,
   810       const ArcFilterMap>(digraph, nfm, afm);
   811   }
   812 
   813 
   814   template <typename _Graph, typename NodeFilterMap,
   815             typename EdgeFilterMap, bool _checked = true>
   816   class SubGraphBase : public GraphAdaptorBase<_Graph> {
   817   public:
   818     typedef _Graph Graph;
   819     typedef SubGraphBase Adaptor;
   820     typedef GraphAdaptorBase<_Graph> Parent;
   821   protected:
   822 
   823     NodeFilterMap* _node_filter_map;
   824     EdgeFilterMap* _edge_filter_map;
   825 
   826     SubGraphBase()
   827       : Parent(), _node_filter_map(0), _edge_filter_map(0) { }
   828 
   829     void setNodeFilterMap(NodeFilterMap& node_filter_map) {
   830       _node_filter_map=&node_filter_map;
   831     }
   832     void setEdgeFilterMap(EdgeFilterMap& edge_filter_map) {
   833       _edge_filter_map=&edge_filter_map;
   834     }
   835 
   836   public:
   837 
   838     typedef typename Parent::Node Node;
   839     typedef typename Parent::Arc Arc;
   840     typedef typename Parent::Edge Edge;
   841 
   842     void first(Node& i) const {
   843       Parent::first(i);
   844       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i);
   845     }
   846 
   847     void first(Arc& i) const {
   848       Parent::first(i);
   849       while (i!=INVALID && (!(*_edge_filter_map)[i]
   850                             || !(*_node_filter_map)[Parent::source(i)]
   851                             || !(*_node_filter_map)[Parent::target(i)]))
   852         Parent::next(i);
   853     }
   854 
   855     void first(Edge& i) const {
   856       Parent::first(i);
   857       while (i!=INVALID && (!(*_edge_filter_map)[i]
   858                             || !(*_node_filter_map)[Parent::u(i)]
   859                             || !(*_node_filter_map)[Parent::v(i)]))
   860         Parent::next(i);
   861     }
   862 
   863     void firstIn(Arc& i, const Node& n) const {
   864       Parent::firstIn(i, n);
   865       while (i!=INVALID && (!(*_edge_filter_map)[i]
   866                             || !(*_node_filter_map)[Parent::source(i)]))
   867         Parent::nextIn(i);
   868     }
   869 
   870     void firstOut(Arc& i, const Node& n) const {
   871       Parent::firstOut(i, n);
   872       while (i!=INVALID && (!(*_edge_filter_map)[i]
   873                             || !(*_node_filter_map)[Parent::target(i)]))
   874         Parent::nextOut(i);
   875     }
   876 
   877     void firstInc(Edge& i, bool& d, const Node& n) const {
   878       Parent::firstInc(i, d, n);
   879       while (i!=INVALID && (!(*_edge_filter_map)[i]
   880                             || !(*_node_filter_map)[Parent::u(i)]
   881                             || !(*_node_filter_map)[Parent::v(i)]))
   882         Parent::nextInc(i, d);
   883     }
   884 
   885     void next(Node& i) const {
   886       Parent::next(i);
   887       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i);
   888     }
   889 
   890     void next(Arc& i) const {
   891       Parent::next(i);
   892       while (i!=INVALID && (!(*_edge_filter_map)[i]
   893                             || !(*_node_filter_map)[Parent::source(i)]
   894                             || !(*_node_filter_map)[Parent::target(i)]))
   895         Parent::next(i);
   896     }
   897 
   898     void next(Edge& i) const {
   899       Parent::next(i);
   900       while (i!=INVALID && (!(*_edge_filter_map)[i]
   901                             || !(*_node_filter_map)[Parent::u(i)]
   902                             || !(*_node_filter_map)[Parent::v(i)]))
   903         Parent::next(i);
   904     }
   905 
   906     void nextIn(Arc& i) const {
   907       Parent::nextIn(i);
   908       while (i!=INVALID && (!(*_edge_filter_map)[i]
   909                             || !(*_node_filter_map)[Parent::source(i)]))
   910         Parent::nextIn(i);
   911     }
   912 
   913     void nextOut(Arc& i) const {
   914       Parent::nextOut(i);
   915       while (i!=INVALID && (!(*_edge_filter_map)[i]
   916                             || !(*_node_filter_map)[Parent::target(i)]))
   917         Parent::nextOut(i);
   918     }
   919 
   920     void nextInc(Edge& i, bool& d) const {
   921       Parent::nextInc(i, d);
   922       while (i!=INVALID && (!(*_edge_filter_map)[i]
   923                             || !(*_node_filter_map)[Parent::u(i)]
   924                             || !(*_node_filter_map)[Parent::v(i)]))
   925         Parent::nextInc(i, d);
   926     }
   927 
   928     void hide(const Node& n) const { _node_filter_map->set(n, false); }
   929     void hide(const Edge& e) const { _edge_filter_map->set(e, false); }
   930 
   931     void unHide(const Node& n) const { _node_filter_map->set(n, true); }
   932     void unHide(const Edge& e) const { _edge_filter_map->set(e, true); }
   933 
   934     bool hidden(const Node& n) const { return !(*_node_filter_map)[n]; }
   935     bool hidden(const Edge& e) const { return !(*_edge_filter_map)[e]; }
   936 
   937     typedef False NodeNumTag;
   938     typedef False EdgeNumTag;
   939 
   940     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;
   941     Arc findArc(const Node& u, const Node& v,
   942                 const Arc& prev = INVALID) {
   943       if (!(*_node_filter_map)[u] || !(*_node_filter_map)[v]) {
   944         return INVALID;
   945       }
   946       Arc arc = Parent::findArc(u, v, prev);
   947       while (arc != INVALID && !(*_edge_filter_map)[arc]) {
   948         arc = Parent::findArc(u, v, arc);
   949       }
   950       return arc;
   951     }
   952     Edge findEdge(const Node& u, const Node& v,
   953                   const Edge& prev = INVALID) {
   954       if (!(*_node_filter_map)[u] || !(*_node_filter_map)[v]) {
   955         return INVALID;
   956       }
   957       Edge edge = Parent::findEdge(u, v, prev);
   958       while (edge != INVALID && !(*_edge_filter_map)[edge]) {
   959         edge = Parent::findEdge(u, v, edge);
   960       }
   961       return edge;
   962     }
   963 
   964     template <typename _Value>
   965     class NodeMap : public SubMapExtender<Adaptor,
   966       typename Parent::template NodeMap<_Value> > {
   967     public:
   968       typedef _Value Value;
   969       typedef SubMapExtender<Adaptor, typename Parent::
   970                              template NodeMap<Value> > MapParent;
   971 
   972       NodeMap(const Adaptor& adaptor)
   973         : MapParent(adaptor) {}
   974       NodeMap(const Adaptor& adaptor, const Value& value)
   975         : MapParent(adaptor, value) {}
   976 
   977     private:
   978       NodeMap& operator=(const NodeMap& cmap) {
   979         return operator=<NodeMap>(cmap);
   980       }
   981 
   982       template <typename CMap>
   983       NodeMap& operator=(const CMap& cmap) {
   984         MapParent::operator=(cmap);
   985         return *this;
   986       }
   987     };
   988 
   989     template <typename _Value>
   990     class ArcMap : public SubMapExtender<Adaptor,
   991       typename Parent::template ArcMap<_Value> > {
   992     public:
   993       typedef _Value Value;
   994       typedef SubMapExtender<Adaptor, typename Parent::
   995                              template ArcMap<Value> > MapParent;
   996 
   997       ArcMap(const Adaptor& adaptor)
   998         : MapParent(adaptor) {}
   999       ArcMap(const Adaptor& adaptor, const Value& value)
  1000         : MapParent(adaptor, value) {}
  1001 
  1002     private:
  1003       ArcMap& operator=(const ArcMap& cmap) {
  1004         return operator=<ArcMap>(cmap);
  1005       }
  1006 
  1007       template <typename CMap>
  1008       ArcMap& operator=(const CMap& cmap) {
  1009         MapParent::operator=(cmap);
  1010         return *this;
  1011       }
  1012     };
  1013 
  1014     template <typename _Value>
  1015     class EdgeMap : public SubMapExtender<Adaptor,
  1016       typename Parent::template EdgeMap<_Value> > {
  1017     public:
  1018       typedef _Value Value;
  1019       typedef SubMapExtender<Adaptor, typename Parent::
  1020                              template EdgeMap<Value> > MapParent;
  1021 
  1022       EdgeMap(const Adaptor& adaptor)
  1023         : MapParent(adaptor) {}
  1024 
  1025       EdgeMap(const Adaptor& adaptor, const Value& value)
  1026         : MapParent(adaptor, value) {}
  1027 
  1028     private:
  1029       EdgeMap& operator=(const EdgeMap& cmap) {
  1030         return operator=<EdgeMap>(cmap);
  1031       }
  1032 
  1033       template <typename CMap>
  1034       EdgeMap& operator=(const CMap& cmap) {
  1035         MapParent::operator=(cmap);
  1036         return *this;
  1037       }
  1038     };
  1039 
  1040   };
  1041 
  1042   template <typename _Graph, typename NodeFilterMap, typename EdgeFilterMap>
  1043   class SubGraphBase<_Graph, NodeFilterMap, EdgeFilterMap, false>
  1044     : public GraphAdaptorBase<_Graph> {
  1045   public:
  1046     typedef _Graph Graph;
  1047     typedef SubGraphBase Adaptor;
  1048     typedef GraphAdaptorBase<_Graph> Parent;
  1049   protected:
  1050     NodeFilterMap* _node_filter_map;
  1051     EdgeFilterMap* _edge_filter_map;
  1052     SubGraphBase() : Parent(),
  1053                      _node_filter_map(0), _edge_filter_map(0) { }
  1054 
  1055     void setNodeFilterMap(NodeFilterMap& node_filter_map) {
  1056       _node_filter_map=&node_filter_map;
  1057     }
  1058     void setEdgeFilterMap(EdgeFilterMap& edge_filter_map) {
  1059       _edge_filter_map=&edge_filter_map;
  1060     }
  1061 
  1062   public:
  1063 
  1064     typedef typename Parent::Node Node;
  1065     typedef typename Parent::Arc Arc;
  1066     typedef typename Parent::Edge Edge;
  1067 
  1068     void first(Node& i) const {
  1069       Parent::first(i);
  1070       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i);
  1071     }
  1072 
  1073     void first(Arc& i) const {
  1074       Parent::first(i);
  1075       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i);
  1076     }
  1077 
  1078     void first(Edge& i) const {
  1079       Parent::first(i);
  1080       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i);
  1081     }
  1082 
  1083     void firstIn(Arc& i, const Node& n) const {
  1084       Parent::firstIn(i, n);
  1085       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextIn(i);
  1086     }
  1087 
  1088     void firstOut(Arc& i, const Node& n) const {
  1089       Parent::firstOut(i, n);
  1090       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextOut(i);
  1091     }
  1092 
  1093     void firstInc(Edge& i, bool& d, const Node& n) const {
  1094       Parent::firstInc(i, d, n);
  1095       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextInc(i, d);
  1096     }
  1097 
  1098     void next(Node& i) const {
  1099       Parent::next(i);
  1100       while (i!=INVALID && !(*_node_filter_map)[i]) Parent::next(i);
  1101     }
  1102     void next(Arc& i) const {
  1103       Parent::next(i);
  1104       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i);
  1105     }
  1106     void next(Edge& i) const {
  1107       Parent::next(i);
  1108       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::next(i);
  1109     }
  1110     void nextIn(Arc& i) const {
  1111       Parent::nextIn(i);
  1112       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextIn(i);
  1113     }
  1114 
  1115     void nextOut(Arc& i) const {
  1116       Parent::nextOut(i);
  1117       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextOut(i);
  1118     }
  1119     void nextInc(Edge& i, bool& d) const {
  1120       Parent::nextInc(i, d);
  1121       while (i!=INVALID && !(*_edge_filter_map)[i]) Parent::nextInc(i, d);
  1122     }
  1123 
  1124     void hide(const Node& n) const { _node_filter_map->set(n, false); }
  1125     void hide(const Edge& e) const { _edge_filter_map->set(e, false); }
  1126 
  1127     void unHide(const Node& n) const { _node_filter_map->set(n, true); }
  1128     void unHide(const Edge& e) const { _edge_filter_map->set(e, true); }
  1129 
  1130     bool hidden(const Node& n) const { return !(*_node_filter_map)[n]; }
  1131     bool hidden(const Edge& e) const { return !(*_edge_filter_map)[e]; }
  1132 
  1133     typedef False NodeNumTag;
  1134     typedef False EdgeNumTag;
  1135 
  1136     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;
  1137     Arc findArc(const Node& u, const Node& v,
  1138                 const Arc& prev = INVALID) {
  1139       Arc arc = Parent::findArc(u, v, prev);
  1140       while (arc != INVALID && !(*_edge_filter_map)[arc]) {
  1141         arc = Parent::findArc(u, v, arc);
  1142       }
  1143       return arc;
  1144     }
  1145     Edge findEdge(const Node& u, const Node& v,
  1146                   const Edge& prev = INVALID) {
  1147       Edge edge = Parent::findEdge(u, v, prev);
  1148       while (edge != INVALID && !(*_edge_filter_map)[edge]) {
  1149         edge = Parent::findEdge(u, v, edge);
  1150       }
  1151       return edge;
  1152     }
  1153 
  1154     template <typename _Value>
  1155     class NodeMap : public SubMapExtender<Adaptor,
  1156       typename Parent::template NodeMap<_Value> > {
  1157     public:
  1158       typedef _Value Value;
  1159       typedef SubMapExtender<Adaptor, typename Parent::
  1160                              template NodeMap<Value> > MapParent;
  1161 
  1162       NodeMap(const Adaptor& adaptor)
  1163         : MapParent(adaptor) {}
  1164       NodeMap(const Adaptor& adaptor, const Value& value)
  1165         : MapParent(adaptor, value) {}
  1166 
  1167     private:
  1168       NodeMap& operator=(const NodeMap& cmap) {
  1169         return operator=<NodeMap>(cmap);
  1170       }
  1171 
  1172       template <typename CMap>
  1173       NodeMap& operator=(const CMap& cmap) {
  1174         MapParent::operator=(cmap);
  1175         return *this;
  1176       }
  1177     };
  1178 
  1179     template <typename _Value>
  1180     class ArcMap : public SubMapExtender<Adaptor,
  1181       typename Parent::template ArcMap<_Value> > {
  1182     public:
  1183       typedef _Value Value;
  1184       typedef SubMapExtender<Adaptor, typename Parent::
  1185                              template ArcMap<Value> > MapParent;
  1186 
  1187       ArcMap(const Adaptor& adaptor)
  1188         : MapParent(adaptor) {}
  1189       ArcMap(const Adaptor& adaptor, const Value& value)
  1190         : MapParent(adaptor, value) {}
  1191 
  1192     private:
  1193       ArcMap& operator=(const ArcMap& cmap) {
  1194         return operator=<ArcMap>(cmap);
  1195       }
  1196 
  1197       template <typename CMap>
  1198       ArcMap& operator=(const CMap& cmap) {
  1199         MapParent::operator=(cmap);
  1200         return *this;
  1201       }
  1202     };
  1203 
  1204     template <typename _Value>
  1205     class EdgeMap : public SubMapExtender<Adaptor,
  1206       typename Parent::template EdgeMap<_Value> > {
  1207     public:
  1208       typedef _Value Value;
  1209       typedef SubMapExtender<Adaptor, typename Parent::
  1210                              template EdgeMap<Value> > MapParent;
  1211 
  1212       EdgeMap(const Adaptor& adaptor)
  1213         : MapParent(adaptor) {}
  1214 
  1215       EdgeMap(const Adaptor& adaptor, const _Value& value)
  1216         : MapParent(adaptor, value) {}
  1217 
  1218     private:
  1219       EdgeMap& operator=(const EdgeMap& cmap) {
  1220         return operator=<EdgeMap>(cmap);
  1221       }
  1222 
  1223       template <typename CMap>
  1224       EdgeMap& operator=(const CMap& cmap) {
  1225         MapParent::operator=(cmap);
  1226         return *this;
  1227       }
  1228     };
  1229 
  1230   };
  1231 
  1232   /// \ingroup graph_adaptors
  1233   ///
  1234   /// \brief A graph adaptor for hiding nodes and edges in an
  1235   /// undirected graph.
  1236   ///
  1237   /// SubGraph hides nodes and edges in a graph. A bool node map and a
  1238   /// bool edge map must be specified, which define the filters for
  1239   /// nodes and edges. Just the nodes and edges with true value are
  1240   /// shown in the subgraph. The SubGraph is conform to the \ref
  1241   /// concepts::Graph "Graph concept". If the \c _checked parameter is
  1242   /// true, then the edges incident to filtered nodes are also
  1243   /// filtered out.
  1244   ///
  1245   /// \tparam _Graph It must be conform to the \ref
  1246   /// concepts::Graph "Graph concept". The type can be specified
  1247   /// to const.
  1248   /// \tparam _NodeFilterMap A bool valued node map of the the adapted graph.
  1249   /// \tparam _EdgeFilterMap A bool valued edge map of the the adapted graph.
  1250   /// \tparam _checked If the parameter is false then the edge filtering
  1251   /// is not checked with respect to node filter. Otherwise, each edge
  1252   /// is automatically filtered, which is incident to a filtered node.
  1253   ///
  1254   /// \see FilterNodes
  1255   /// \see FilterEdges
  1256   template<typename _Graph, typename NodeFilterMap,
  1257            typename EdgeFilterMap, bool _checked = true>
  1258   class SubGraph
  1259     : public GraphAdaptorExtender<
  1260       SubGraphBase<_Graph, NodeFilterMap, EdgeFilterMap, _checked> > {
  1261   public:
  1262     typedef _Graph Graph;
  1263     typedef GraphAdaptorExtender<
  1264       SubGraphBase<_Graph, NodeFilterMap, EdgeFilterMap> > Parent;
  1265 
  1266     typedef typename Parent::Node Node;
  1267     typedef typename Parent::Edge Edge;
  1268 
  1269   protected:
  1270     SubGraph() { }
  1271   public:
  1272 
  1273     /// \brief Constructor
  1274     ///
  1275     /// Creates a subgraph for the given graph with given node and
  1276     /// edge map filters.
  1277     SubGraph(Graph& _graph, NodeFilterMap& node_filter_map,
  1278              EdgeFilterMap& edge_filter_map) {
  1279       setGraph(_graph);
  1280       setNodeFilterMap(node_filter_map);
  1281       setEdgeFilterMap(edge_filter_map);
  1282     }
  1283 
  1284     /// \brief Hides the node of the graph
  1285     ///
  1286     /// This function hides \c n in the graph, i.e. the iteration
  1287     /// jumps over it. This is done by simply setting the value of \c n
  1288     /// to be false in the corresponding node-map.
  1289     void hide(const Node& n) const { Parent::hide(n); }
  1290 
  1291     /// \brief Hides the edge of the graph
  1292     ///
  1293     /// This function hides \c e in the graph, i.e. the iteration
  1294     /// jumps over it. This is done by simply setting the value of \c e
  1295     /// to be false in the corresponding edge-map.
  1296     void hide(const Edge& e) const { Parent::hide(e); }
  1297 
  1298     /// \brief Unhides the node of the graph
  1299     ///
  1300     /// The value of \c n is set to be true in the node-map which stores
  1301     /// hide information. If \c n was hidden previuosly, then it is shown
  1302     /// again
  1303     void unHide(const Node& n) const { Parent::unHide(n); }
  1304 
  1305     /// \brief Unhides the edge of the graph
  1306     ///
  1307     /// The value of \c e is set to be true in the edge-map which stores
  1308     /// hide information. If \c e was hidden previuosly, then it is shown
  1309     /// again
  1310     void unHide(const Edge& e) const { Parent::unHide(e); }
  1311 
  1312     /// \brief Returns true if \c n is hidden.
  1313     ///
  1314     /// Returns true if \c n is hidden.
  1315     ///
  1316     bool hidden(const Node& n) const { return Parent::hidden(n); }
  1317 
  1318     /// \brief Returns true if \c e is hidden.
  1319     ///
  1320     /// Returns true if \c e is hidden.
  1321     ///
  1322     bool hidden(const Edge& e) const { return Parent::hidden(e); }
  1323   };
  1324 
  1325   /// \brief Just gives back a subgraph
  1326   ///
  1327   /// Just gives back a subgraph
  1328   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>
  1329   SubGraph<const Graph, NodeFilterMap, ArcFilterMap>
  1330   subGraph(const Graph& graph, NodeFilterMap& nfm, ArcFilterMap& efm) {
  1331     return SubGraph<const Graph, NodeFilterMap, ArcFilterMap>(graph, nfm, efm);
  1332   }
  1333 
  1334   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>
  1335   SubGraph<const Graph, const NodeFilterMap, ArcFilterMap>
  1336   subGraph(const Graph& graph,
  1337            const NodeFilterMap& nfm, ArcFilterMap& efm) {
  1338     return SubGraph<const Graph, const NodeFilterMap, ArcFilterMap>
  1339       (graph, nfm, efm);
  1340   }
  1341 
  1342   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>
  1343   SubGraph<const Graph, NodeFilterMap, const ArcFilterMap>
  1344   subGraph(const Graph& graph,
  1345            NodeFilterMap& nfm, const ArcFilterMap& efm) {
  1346     return SubGraph<const Graph, NodeFilterMap, const ArcFilterMap>
  1347       (graph, nfm, efm);
  1348   }
  1349 
  1350   template<typename Graph, typename NodeFilterMap, typename ArcFilterMap>
  1351   SubGraph<const Graph, const NodeFilterMap, const ArcFilterMap>
  1352   subGraph(const Graph& graph,
  1353            const NodeFilterMap& nfm, const ArcFilterMap& efm) {
  1354     return SubGraph<const Graph, const NodeFilterMap, const ArcFilterMap>
  1355       (graph, nfm, efm);
  1356   }
  1357 
  1358   /// \ingroup graph_adaptors
  1359   ///
  1360   /// \brief An adaptor for hiding nodes from a digraph or a graph.
  1361   ///
  1362   /// FilterNodes adaptor hides nodes in a graph or a digraph. A bool
  1363   /// node map must be specified, which defines the filters for
  1364   /// nodes. Just the unfiltered nodes and the arcs or edges incident
  1365   /// to unfiltered nodes are shown in the subdigraph or subgraph. The
  1366   /// FilterNodes is conform to the \ref concepts::Digraph
  1367   /// "Digraph concept" or \ref concepts::Graph "Graph concept" depending
  1368   /// on the \c _Digraph template parameter. If the \c _checked
  1369   /// parameter is true, then the arc or edges incident to filtered nodes
  1370   /// are also filtered out.
  1371   ///
  1372   /// \tparam _Digraph It must be conform to the \ref
  1373   /// concepts::Digraph "Digraph concept" or \ref concepts::Graph
  1374   /// "Graph concept". The type can be specified to be const.
  1375   /// \tparam _NodeFilterMap A bool valued node map of the the adapted graph.
  1376   /// \tparam _checked If the parameter is false then the arc or edge
  1377   /// filtering is not checked with respect to node filter. In this
  1378   /// case just isolated nodes can be filtered out from the
  1379   /// graph.
  1380 #ifdef DOXYGEN
  1381   template<typename _Digraph,
  1382            typename _NodeFilterMap = typename _Digraph::template NodeMap<bool>,
  1383            bool _checked = true>
  1384 #else
  1385   template<typename _Digraph,
  1386            typename _NodeFilterMap = typename _Digraph::template NodeMap<bool>,
  1387            bool _checked = true,
  1388            typename Enable = void>
  1389 #endif
  1390   class FilterNodes
  1391     : public SubDigraph<_Digraph, _NodeFilterMap,
  1392                         ConstMap<typename _Digraph::Arc, bool>, _checked> {
  1393   public:
  1394 
  1395     typedef _Digraph Digraph;
  1396     typedef _NodeFilterMap NodeFilterMap;
  1397 
  1398     typedef SubDigraph<Digraph, NodeFilterMap,
  1399                        ConstMap<typename Digraph::Arc, bool>, _checked>
  1400     Parent;
  1401 
  1402     typedef typename Parent::Node Node;
  1403 
  1404   protected:
  1405     ConstMap<typename Digraph::Arc, bool> const_true_map;
  1406 
  1407     FilterNodes() : const_true_map(true) {
  1408       Parent::setArcFilterMap(const_true_map);
  1409     }
  1410 
  1411   public:
  1412 
  1413     /// \brief Constructor
  1414     ///
  1415     /// Creates an adaptor for the given digraph or graph with
  1416     /// given node filter map.
  1417     FilterNodes(Digraph& _digraph, NodeFilterMap& node_filter) :
  1418       Parent(), const_true_map(true) {
  1419       Parent::setDigraph(_digraph);
  1420       Parent::setNodeFilterMap(node_filter);
  1421       Parent::setArcFilterMap(const_true_map);
  1422     }
  1423 
  1424     /// \brief Hides the node of the graph
  1425     ///
  1426     /// This function hides \c n in the digraph or graph, i.e. the iteration
  1427     /// jumps over it. This is done by simply setting the value of \c n
  1428     /// to be false in the corresponding node map.
  1429     void hide(const Node& n) const { Parent::hide(n); }
  1430 
  1431     /// \brief Unhides the node of the graph
  1432     ///
  1433     /// The value of \c n is set to be true in the node-map which stores
  1434     /// hide information. If \c n was hidden previuosly, then it is shown
  1435     /// again
  1436     void unHide(const Node& n) const { Parent::unHide(n); }
  1437 
  1438     /// \brief Returns true if \c n is hidden.
  1439     ///
  1440     /// Returns true if \c n is hidden.
  1441     ///
  1442     bool hidden(const Node& n) const { return Parent::hidden(n); }
  1443 
  1444   };
  1445 
  1446   template<typename _Graph, typename _NodeFilterMap, bool _checked>
  1447   class FilterNodes<_Graph, _NodeFilterMap, _checked,
  1448                     typename enable_if<UndirectedTagIndicator<_Graph> >::type>
  1449     : public SubGraph<_Graph, _NodeFilterMap,
  1450                       ConstMap<typename _Graph::Edge, bool>, _checked> {
  1451   public:
  1452     typedef _Graph Graph;
  1453     typedef _NodeFilterMap NodeFilterMap;
  1454     typedef SubGraph<Graph, NodeFilterMap,
  1455                      ConstMap<typename Graph::Edge, bool> > Parent;
  1456 
  1457     typedef typename Parent::Node Node;
  1458   protected:
  1459     ConstMap<typename Graph::Edge, bool> const_true_map;
  1460 
  1461     FilterNodes() : const_true_map(true) {
  1462       Parent::setEdgeFilterMap(const_true_map);
  1463     }
  1464 
  1465   public:
  1466 
  1467     FilterNodes(Graph& _graph, NodeFilterMap& node_filter_map) :
  1468       Parent(), const_true_map(true) {
  1469       Parent::setGraph(_graph);
  1470       Parent::setNodeFilterMap(node_filter_map);
  1471       Parent::setEdgeFilterMap(const_true_map);
  1472     }
  1473 
  1474     void hide(const Node& n) const { Parent::hide(n); }
  1475     void unHide(const Node& n) const { Parent::unHide(n); }
  1476     bool hidden(const Node& n) const { return Parent::hidden(n); }
  1477 
  1478   };
  1479 
  1480 
  1481   /// \brief Just gives back a FilterNodes adaptor
  1482   ///
  1483   /// Just gives back a FilterNodes adaptor
  1484   template<typename Digraph, typename NodeFilterMap>
  1485   FilterNodes<const Digraph, NodeFilterMap>
  1486   filterNodes(const Digraph& digraph, NodeFilterMap& nfm) {
  1487     return FilterNodes<const Digraph, NodeFilterMap>(digraph, nfm);
  1488   }
  1489 
  1490   template<typename Digraph, typename NodeFilterMap>
  1491   FilterNodes<const Digraph, const NodeFilterMap>
  1492   filterNodes(const Digraph& digraph, const NodeFilterMap& nfm) {
  1493     return FilterNodes<const Digraph, const NodeFilterMap>(digraph, nfm);
  1494   }
  1495 
  1496   /// \ingroup graph_adaptors
  1497   ///
  1498   /// \brief An adaptor for hiding arcs from a digraph.
  1499   ///
  1500   /// FilterArcs adaptor hides arcs in a digraph. A bool arc map must
  1501   /// be specified, which defines the filters for arcs. Just the
  1502   /// unfiltered arcs are shown in the subdigraph. The FilterArcs is
  1503   /// conform to the \ref concepts::Digraph "Digraph concept".
  1504   ///
  1505   /// \tparam _Digraph It must be conform to the \ref concepts::Digraph
  1506   /// "Digraph concept". The type can be specified to be const.
  1507   /// \tparam _ArcFilterMap A bool valued arc map of the the adapted
  1508   /// graph.
  1509   template<typename _Digraph, typename _ArcFilterMap>
  1510   class FilterArcs :
  1511     public SubDigraph<_Digraph, ConstMap<typename _Digraph::Node, bool>,
  1512                       _ArcFilterMap, false> {
  1513   public:
  1514     typedef _Digraph Digraph;
  1515     typedef _ArcFilterMap ArcFilterMap;
  1516 
  1517     typedef SubDigraph<Digraph, ConstMap<typename Digraph::Node, bool>,
  1518                        ArcFilterMap, false> Parent;
  1519 
  1520     typedef typename Parent::Arc Arc;
  1521 
  1522   protected:
  1523     ConstMap<typename Digraph::Node, bool> const_true_map;
  1524 
  1525     FilterArcs() : const_true_map(true) {
  1526       Parent::setNodeFilterMap(const_true_map);
  1527     }
  1528 
  1529   public:
  1530 
  1531     /// \brief Constructor
  1532     ///
  1533     /// Creates a FilterArcs adaptor for the given graph with
  1534     /// given arc map filter.
  1535     FilterArcs(Digraph& digraph, ArcFilterMap& arc_filter)
  1536       : Parent(), const_true_map(true) {
  1537       Parent::setDigraph(digraph);
  1538       Parent::setNodeFilterMap(const_true_map);
  1539       Parent::setArcFilterMap(arc_filter);
  1540     }
  1541 
  1542     /// \brief Hides the arc of the graph
  1543     ///
  1544     /// This function hides \c a in the graph, i.e. the iteration
  1545     /// jumps over it. This is done by simply setting the value of \c a
  1546     /// to be false in the corresponding arc map.
  1547     void hide(const Arc& a) const { Parent::hide(a); }
  1548 
  1549     /// \brief Unhides the arc of the graph
  1550     ///
  1551     /// The value of \c a is set to be true in the arc-map which stores
  1552     /// hide information. If \c a was hidden previuosly, then it is shown
  1553     /// again
  1554     void unHide(const Arc& a) const { Parent::unHide(a); }
  1555 
  1556     /// \brief Returns true if \c a is hidden.
  1557     ///
  1558     /// Returns true if \c a is hidden.
  1559     ///
  1560     bool hidden(const Arc& a) const { return Parent::hidden(a); }
  1561 
  1562   };
  1563 
  1564   /// \brief Just gives back an FilterArcs adaptor
  1565   ///
  1566   /// Just gives back an FilterArcs adaptor
  1567   template<typename Digraph, typename ArcFilterMap>
  1568   FilterArcs<const Digraph, ArcFilterMap>
  1569   filterArcs(const Digraph& digraph, ArcFilterMap& afm) {
  1570     return FilterArcs<const Digraph, ArcFilterMap>(digraph, afm);
  1571   }
  1572 
  1573   template<typename Digraph, typename ArcFilterMap>
  1574   FilterArcs<const Digraph, const ArcFilterMap>
  1575   filterArcs(const Digraph& digraph, const ArcFilterMap& afm) {
  1576     return FilterArcs<const Digraph, const ArcFilterMap>(digraph, afm);
  1577   }
  1578 
  1579   /// \ingroup graph_adaptors
  1580   ///
  1581   /// \brief An adaptor for hiding edges from a graph.
  1582   ///
  1583   /// FilterEdges adaptor hides edges in a digraph. A bool edge map must
  1584   /// be specified, which defines the filters for edges. Just the
  1585   /// unfiltered edges are shown in the subdigraph. The FilterEdges is
  1586   /// conform to the \ref concepts::Graph "Graph concept".
  1587   ///
  1588   /// \tparam _Graph It must be conform to the \ref concepts::Graph
  1589   /// "Graph concept". The type can be specified to be const.
  1590   /// \tparam _EdgeFilterMap A bool valued edge map of the the adapted
  1591   /// graph.
  1592   template<typename _Graph, typename _EdgeFilterMap>
  1593   class FilterEdges :
  1594     public SubGraph<_Graph, ConstMap<typename _Graph::Node,bool>,
  1595                     _EdgeFilterMap, false> {
  1596   public:
  1597     typedef _Graph Graph;
  1598     typedef _EdgeFilterMap EdgeFilterMap;
  1599     typedef SubGraph<Graph, ConstMap<typename Graph::Node,bool>,
  1600                      EdgeFilterMap, false> Parent;
  1601     typedef typename Parent::Edge Edge;
  1602   protected:
  1603     ConstMap<typename Graph::Node, bool> const_true_map;
  1604 
  1605     FilterEdges() : const_true_map(true) {
  1606       Parent::setNodeFilterMap(const_true_map);
  1607     }
  1608 
  1609   public:
  1610 
  1611     /// \brief Constructor
  1612     ///
  1613     /// Creates a FilterEdges adaptor for the given graph with
  1614     /// given edge map filters.
  1615     FilterEdges(Graph& _graph, EdgeFilterMap& edge_filter_map) :
  1616       Parent(), const_true_map(true) {
  1617       Parent::setGraph(_graph);
  1618       Parent::setNodeFilterMap(const_true_map);
  1619       Parent::setEdgeFilterMap(edge_filter_map);
  1620     }
  1621 
  1622     /// \brief Hides the edge of the graph
  1623     ///
  1624     /// This function hides \c e in the graph, i.e. the iteration
  1625     /// jumps over it. This is done by simply setting the value of \c e
  1626     /// to be false in the corresponding edge-map.
  1627     void hide(const Edge& e) const { Parent::hide(e); }
  1628 
  1629     /// \brief Unhides the edge of the graph
  1630     ///
  1631     /// The value of \c e is set to be true in the edge-map which stores
  1632     /// hide information. If \c e was hidden previuosly, then it is shown
  1633     /// again
  1634     void unHide(const Edge& e) const { Parent::unHide(e); }
  1635 
  1636     /// \brief Returns true if \c e is hidden.
  1637     ///
  1638     /// Returns true if \c e is hidden.
  1639     ///
  1640     bool hidden(const Edge& e) const { return Parent::hidden(e); }
  1641 
  1642   };
  1643 
  1644   /// \brief Just gives back a FilterEdges adaptor
  1645   ///
  1646   /// Just gives back a FilterEdges adaptor
  1647   template<typename Graph, typename EdgeFilterMap>
  1648   FilterEdges<const Graph, EdgeFilterMap>
  1649   filterEdges(const Graph& graph, EdgeFilterMap& efm) {
  1650     return FilterEdges<const Graph, EdgeFilterMap>(graph, efm);
  1651   }
  1652 
  1653   template<typename Graph, typename EdgeFilterMap>
  1654   FilterEdges<const Graph, const EdgeFilterMap>
  1655   filterEdges(const Graph& graph, const EdgeFilterMap& efm) {
  1656     return FilterEdges<const Graph, const EdgeFilterMap>(graph, efm);
  1657   }
  1658 
  1659   template <typename _Digraph>
  1660   class UndirectorBase {
  1661   public:
  1662     typedef _Digraph Digraph;
  1663     typedef UndirectorBase Adaptor;
  1664 
  1665     typedef True UndirectedTag;
  1666 
  1667     typedef typename Digraph::Arc Edge;
  1668     typedef typename Digraph::Node Node;
  1669 
  1670     class Arc : public Edge {
  1671       friend class UndirectorBase;
  1672     protected:
  1673       bool _forward;
  1674 
  1675       Arc(const Edge& edge, bool forward) :
  1676         Edge(edge), _forward(forward) {}
  1677 
  1678     public:
  1679       Arc() {}
  1680 
  1681       Arc(Invalid) : Edge(INVALID), _forward(true) {}
  1682 
  1683       bool operator==(const Arc &other) const {
  1684         return _forward == other._forward &&
  1685           static_cast<const Edge&>(*this) == static_cast<const Edge&>(other);
  1686       }
  1687       bool operator!=(const Arc &other) const {
  1688         return _forward != other._forward ||
  1689           static_cast<const Edge&>(*this) != static_cast<const Edge&>(other);
  1690       }
  1691       bool operator<(const Arc &other) const {
  1692         return _forward < other._forward ||
  1693           (_forward == other._forward &&
  1694            static_cast<const Edge&>(*this) < static_cast<const Edge&>(other));
  1695       }
  1696     };
  1697 
  1698 
  1699 
  1700     void first(Node& n) const {
  1701       _digraph->first(n);
  1702     }
  1703 
  1704     void next(Node& n) const {
  1705       _digraph->next(n);
  1706     }
  1707 
  1708     void first(Arc& a) const {
  1709       _digraph->first(a);
  1710       a._forward = true;
  1711     }
  1712 
  1713     void next(Arc& a) const {
  1714       if (a._forward) {
  1715         a._forward = false;
  1716       } else {
  1717         _digraph->next(a);
  1718         a._forward = true;
  1719       }
  1720     }
  1721 
  1722     void first(Edge& e) const {
  1723       _digraph->first(e);
  1724     }
  1725 
  1726     void next(Edge& e) const {
  1727       _digraph->next(e);
  1728     }
  1729 
  1730     void firstOut(Arc& a, const Node& n) const {
  1731       _digraph->firstIn(a, n);
  1732       if( static_cast<const Edge&>(a) != INVALID ) {
  1733         a._forward = false;
  1734       } else {
  1735         _digraph->firstOut(a, n);
  1736         a._forward = true;
  1737       }
  1738     }
  1739     void nextOut(Arc &a) const {
  1740       if (!a._forward) {
  1741         Node n = _digraph->target(a);
  1742         _digraph->nextIn(a);
  1743         if (static_cast<const Edge&>(a) == INVALID ) {
  1744           _digraph->firstOut(a, n);
  1745           a._forward = true;
  1746         }
  1747       }
  1748       else {
  1749         _digraph->nextOut(a);
  1750       }
  1751     }
  1752 
  1753     void firstIn(Arc &a, const Node &n) const {
  1754       _digraph->firstOut(a, n);
  1755       if (static_cast<const Edge&>(a) != INVALID ) {
  1756         a._forward = false;
  1757       } else {
  1758         _digraph->firstIn(a, n);
  1759         a._forward = true;
  1760       }
  1761     }
  1762     void nextIn(Arc &a) const {
  1763       if (!a._forward) {
  1764         Node n = _digraph->source(a);
  1765         _digraph->nextOut(a);
  1766         if( static_cast<const Edge&>(a) == INVALID ) {
  1767           _digraph->firstIn(a, n);
  1768           a._forward = true;
  1769         }
  1770       }
  1771       else {
  1772         _digraph->nextIn(a);
  1773       }
  1774     }
  1775 
  1776     void firstInc(Edge &e, bool &d, const Node &n) const {
  1777       d = true;
  1778       _digraph->firstOut(e, n);
  1779       if (e != INVALID) return;
  1780       d = false;
  1781       _digraph->firstIn(e, n);
  1782     }
  1783 
  1784     void nextInc(Edge &e, bool &d) const {
  1785       if (d) {
  1786         Node s = _digraph->source(e);
  1787         _digraph->nextOut(e);
  1788         if (e != INVALID) return;
  1789         d = false;
  1790         _digraph->firstIn(e, s);
  1791       } else {
  1792         _digraph->nextIn(e);
  1793       }
  1794     }
  1795 
  1796     Node u(const Edge& e) const {
  1797       return _digraph->source(e);
  1798     }
  1799 
  1800     Node v(const Edge& e) const {
  1801       return _digraph->target(e);
  1802     }
  1803 
  1804     Node source(const Arc &a) const {
  1805       return a._forward ? _digraph->source(a) : _digraph->target(a);
  1806     }
  1807 
  1808     Node target(const Arc &a) const {
  1809       return a._forward ? _digraph->target(a) : _digraph->source(a);
  1810     }
  1811 
  1812     static Arc direct(const Edge &e, bool d) {
  1813       return Arc(e, d);
  1814     }
  1815     Arc direct(const Edge &e, const Node& n) const {
  1816       return Arc(e, _digraph->source(e) == n);
  1817     }
  1818 
  1819     static bool direction(const Arc &a) { return a._forward; }
  1820 
  1821     Node nodeFromId(int ix) const { return _digraph->nodeFromId(ix); }
  1822     Arc arcFromId(int ix) const {
  1823       return direct(_digraph->arcFromId(ix >> 1), bool(ix & 1));
  1824     }
  1825     Edge edgeFromId(int ix) const { return _digraph->arcFromId(ix); }
  1826 
  1827     int id(const Node &n) const { return _digraph->id(n); }
  1828     int id(const Arc &a) const {
  1829       return  (_digraph->id(a) << 1) | (a._forward ? 1 : 0);
  1830     }
  1831     int id(const Edge &e) const { return _digraph->id(e); }
  1832 
  1833     int maxNodeId() const { return _digraph->maxNodeId(); }
  1834     int maxArcId() const { return (_digraph->maxArcId() << 1) | 1; }
  1835     int maxEdgeId() const { return _digraph->maxArcId(); }
  1836 
  1837     Node addNode() { return _digraph->addNode(); }
  1838     Edge addEdge(const Node& u, const Node& v) {
  1839       return _digraph->addArc(u, v);
  1840     }
  1841 
  1842     void erase(const Node& i) { _digraph->erase(i); }
  1843     void erase(const Edge& i) { _digraph->erase(i); }
  1844 
  1845     void clear() { _digraph->clear(); }
  1846 
  1847     typedef NodeNumTagIndicator<Digraph> NodeNumTag;
  1848     int nodeNum() const { return 2 * _digraph->arcNum(); }
  1849     typedef EdgeNumTagIndicator<Digraph> EdgeNumTag;
  1850     int arcNum() const { return 2 * _digraph->arcNum(); }
  1851     int edgeNum() const { return _digraph->arcNum(); }
  1852 
  1853     typedef FindEdgeTagIndicator<Digraph> FindEdgeTag;
  1854     Arc findArc(Node s, Node t, Arc p = INVALID) const {
  1855       if (p == INVALID) {
  1856         Edge arc = _digraph->findArc(s, t);
  1857         if (arc != INVALID) return direct(arc, true);
  1858         arc = _digraph->findArc(t, s);
  1859         if (arc != INVALID) return direct(arc, false);
  1860       } else if (direction(p)) {
  1861         Edge arc = _digraph->findArc(s, t, p);
  1862         if (arc != INVALID) return direct(arc, true);
  1863         arc = _digraph->findArc(t, s);
  1864         if (arc != INVALID) return direct(arc, false);
  1865       } else {
  1866         Edge arc = _digraph->findArc(t, s, p);
  1867         if (arc != INVALID) return direct(arc, false);
  1868       }
  1869       return INVALID;
  1870     }
  1871 
  1872     Edge findEdge(Node s, Node t, Edge p = INVALID) const {
  1873       if (s != t) {
  1874         if (p == INVALID) {
  1875           Edge arc = _digraph->findArc(s, t);
  1876           if (arc != INVALID) return arc;
  1877           arc = _digraph->findArc(t, s);
  1878           if (arc != INVALID) return arc;
  1879         } else if (_digraph->s(p) == s) {
  1880           Edge arc = _digraph->findArc(s, t, p);
  1881           if (arc != INVALID) return arc;
  1882           arc = _digraph->findArc(t, s);
  1883           if (arc != INVALID) return arc;
  1884         } else {
  1885           Edge arc = _digraph->findArc(t, s, p);
  1886           if (arc != INVALID) return arc;
  1887         }
  1888       } else {
  1889         return _digraph->findArc(s, t, p);
  1890       }
  1891       return INVALID;
  1892     }
  1893 
  1894   private:
  1895 
  1896     template <typename _Value>
  1897     class ArcMapBase {
  1898     private:
  1899 
  1900       typedef typename Digraph::template ArcMap<_Value> MapImpl;
  1901 
  1902     public:
  1903 
  1904       typedef typename MapTraits<MapImpl>::ReferenceMapTag ReferenceMapTag;
  1905 
  1906       typedef _Value Value;
  1907       typedef Arc Key;
  1908 
  1909       ArcMapBase(const Adaptor& adaptor) :
  1910         _forward(*adaptor._digraph), _backward(*adaptor._digraph) {}
  1911 
  1912       ArcMapBase(const Adaptor& adaptor, const Value& v)
  1913         : _forward(*adaptor._digraph, v), _backward(*adaptor._digraph, v) {}
  1914 
  1915       void set(const Arc& a, const Value& v) {
  1916         if (direction(a)) {
  1917           _forward.set(a, v);
  1918         } else {
  1919           _backward.set(a, v);
  1920         }
  1921       }
  1922 
  1923       typename MapTraits<MapImpl>::ConstReturnValue
  1924       operator[](const Arc& a) const {
  1925         if (direction(a)) {
  1926           return _forward[a];
  1927         } else {
  1928           return _backward[a];
  1929         }
  1930       }
  1931 
  1932       typename MapTraits<MapImpl>::ReturnValue
  1933       operator[](const Arc& a) {
  1934         if (direction(a)) {
  1935           return _forward[a];
  1936         } else {
  1937           return _backward[a];
  1938         }
  1939       }
  1940 
  1941     protected:
  1942 
  1943       MapImpl _forward, _backward;
  1944 
  1945     };
  1946 
  1947   public:
  1948 
  1949     template <typename _Value>
  1950     class NodeMap : public Digraph::template NodeMap<_Value> {
  1951     public:
  1952 
  1953       typedef _Value Value;
  1954       typedef typename Digraph::template NodeMap<Value> Parent;
  1955 
  1956       explicit NodeMap(const Adaptor& adaptor)
  1957         : Parent(*adaptor._digraph) {}
  1958 
  1959       NodeMap(const Adaptor& adaptor, const _Value& value)
  1960         : Parent(*adaptor._digraph, value) { }
  1961 
  1962     private:
  1963       NodeMap& operator=(const NodeMap& cmap) {
  1964         return operator=<NodeMap>(cmap);
  1965       }
  1966 
  1967       template <typename CMap>
  1968       NodeMap& operator=(const CMap& cmap) {
  1969         Parent::operator=(cmap);
  1970         return *this;
  1971       }
  1972 
  1973     };
  1974 
  1975     template <typename _Value>
  1976     class ArcMap
  1977       : public SubMapExtender<Adaptor, ArcMapBase<_Value> >
  1978     {
  1979     public:
  1980       typedef _Value Value;
  1981       typedef SubMapExtender<Adaptor, ArcMapBase<Value> > Parent;
  1982 
  1983       ArcMap(const Adaptor& adaptor)
  1984         : Parent(adaptor) {}
  1985 
  1986       ArcMap(const Adaptor& adaptor, const Value& value)
  1987         : Parent(adaptor, value) {}
  1988 
  1989     private:
  1990       ArcMap& operator=(const ArcMap& cmap) {
  1991         return operator=<ArcMap>(cmap);
  1992       }
  1993 
  1994       template <typename CMap>
  1995       ArcMap& operator=(const CMap& cmap) {
  1996         Parent::operator=(cmap);
  1997         return *this;
  1998       }
  1999     };
  2000 
  2001     template <typename _Value>
  2002     class EdgeMap : public Digraph::template ArcMap<_Value> {
  2003     public:
  2004 
  2005       typedef _Value Value;
  2006       typedef typename Digraph::template ArcMap<Value> Parent;
  2007 
  2008       explicit EdgeMap(const Adaptor& adaptor)
  2009         : Parent(*adaptor._digraph) {}
  2010 
  2011       EdgeMap(const Adaptor& adaptor, const Value& value)
  2012         : Parent(*adaptor._digraph, value) {}
  2013 
  2014     private:
  2015       EdgeMap& operator=(const EdgeMap& cmap) {
  2016         return operator=<EdgeMap>(cmap);
  2017       }
  2018 
  2019       template <typename CMap>
  2020       EdgeMap& operator=(const CMap& cmap) {
  2021         Parent::operator=(cmap);
  2022         return *this;
  2023       }
  2024 
  2025     };
  2026 
  2027     typedef typename ItemSetTraits<Digraph, Node>::ItemNotifier NodeNotifier;
  2028     NodeNotifier& notifier(Node) const { return _digraph->notifier(Node()); }
  2029 
  2030   protected:
  2031 
  2032     UndirectorBase() : _digraph(0) {}
  2033 
  2034     Digraph* _digraph;
  2035 
  2036     void setDigraph(Digraph& digraph) {
  2037       _digraph = &digraph;
  2038     }
  2039 
  2040   };
  2041 
  2042   /// \ingroup graph_adaptors
  2043   ///
  2044   /// \brief Undirect the graph
  2045   ///
  2046   /// This adaptor makes an undirected graph from a directed
  2047   /// graph. All arcs of the underlying digraph will be showed in the
  2048   /// adaptor as an edge. The Orienter adaptor is conform to the \ref
  2049   /// concepts::Graph "Graph concept".
  2050   ///
  2051   /// \tparam _Digraph It must be conform to the \ref
  2052   /// concepts::Digraph "Digraph concept". The type can be specified
  2053   /// to const.
  2054   template<typename _Digraph>
  2055   class Undirector
  2056     : public GraphAdaptorExtender<UndirectorBase<_Digraph> > {
  2057   public:
  2058     typedef _Digraph Digraph;
  2059     typedef GraphAdaptorExtender<UndirectorBase<Digraph> > Parent;
  2060   protected:
  2061     Undirector() { }
  2062   public:
  2063 
  2064     /// \brief Constructor
  2065     ///
  2066     /// Creates a undirected graph from the given digraph
  2067     Undirector(_Digraph& digraph) {
  2068       setDigraph(digraph);
  2069     }
  2070 
  2071     /// \brief ArcMap combined from two original ArcMap
  2072     ///
  2073     /// This class adapts two original digraph ArcMap to
  2074     /// get an arc map on the undirected graph.
  2075     template <typename _ForwardMap, typename _BackwardMap>
  2076     class CombinedArcMap {
  2077     public:
  2078 
  2079       typedef _ForwardMap ForwardMap;
  2080       typedef _BackwardMap BackwardMap;
  2081 
  2082       typedef typename MapTraits<ForwardMap>::ReferenceMapTag ReferenceMapTag;
  2083 
  2084       typedef typename ForwardMap::Value Value;
  2085       typedef typename Parent::Arc Key;
  2086 
  2087       /// \brief Constructor
  2088       ///
  2089       /// Constructor
  2090       CombinedArcMap(ForwardMap& forward, BackwardMap& backward)
  2091         : _forward(&forward), _backward(&backward) {}
  2092 
  2093 
  2094       /// \brief Sets the value associated with a key.
  2095       ///
  2096       /// Sets the value associated with a key.
  2097       void set(const Key& e, const Value& a) {
  2098         if (Parent::direction(e)) {
  2099           _forward->set(e, a);
  2100         } else {
  2101           _backward->set(e, a);
  2102         }
  2103       }
  2104 
  2105       /// \brief Returns the value associated with a key.
  2106       ///
  2107       /// Returns the value associated with a key.
  2108       typename MapTraits<ForwardMap>::ConstReturnValue
  2109       operator[](const Key& e) const {
  2110         if (Parent::direction(e)) {
  2111           return (*_forward)[e];
  2112         } else {
  2113           return (*_backward)[e];
  2114         }
  2115       }
  2116 
  2117       /// \brief Returns the value associated with a key.
  2118       ///
  2119       /// Returns the value associated with a key.
  2120       typename MapTraits<ForwardMap>::ReturnValue
  2121       operator[](const Key& e) {
  2122         if (Parent::direction(e)) {
  2123           return (*_forward)[e];
  2124         } else {
  2125           return (*_backward)[e];
  2126         }
  2127       }
  2128 
  2129     protected:
  2130 
  2131       ForwardMap* _forward;
  2132       BackwardMap* _backward;
  2133 
  2134     };
  2135 
  2136     /// \brief Just gives back a combined arc map
  2137     ///
  2138     /// Just gives back a combined arc map
  2139     template <typename ForwardMap, typename BackwardMap>
  2140     static CombinedArcMap<ForwardMap, BackwardMap>
  2141     combinedArcMap(ForwardMap& forward, BackwardMap& backward) {
  2142       return CombinedArcMap<ForwardMap, BackwardMap>(forward, backward);
  2143     }
  2144 
  2145     template <typename ForwardMap, typename BackwardMap>
  2146     static CombinedArcMap<const ForwardMap, BackwardMap>
  2147     combinedArcMap(const ForwardMap& forward, BackwardMap& backward) {
  2148       return CombinedArcMap<const ForwardMap,
  2149         BackwardMap>(forward, backward);
  2150     }
  2151 
  2152     template <typename ForwardMap, typename BackwardMap>
  2153     static CombinedArcMap<ForwardMap, const BackwardMap>
  2154     combinedArcMap(ForwardMap& forward, const BackwardMap& backward) {
  2155       return CombinedArcMap<ForwardMap,
  2156         const BackwardMap>(forward, backward);
  2157     }
  2158 
  2159     template <typename ForwardMap, typename BackwardMap>
  2160     static CombinedArcMap<const ForwardMap, const BackwardMap>
  2161     combinedArcMap(const ForwardMap& forward, const BackwardMap& backward) {
  2162       return CombinedArcMap<const ForwardMap,
  2163         const BackwardMap>(forward, backward);
  2164     }
  2165 
  2166   };
  2167 
  2168   /// \brief Just gives back an undirected view of the given digraph
  2169   ///
  2170   /// Just gives back an undirected view of the given digraph
  2171   template<typename Digraph>
  2172   Undirector<const Digraph>
  2173   undirector(const Digraph& digraph) {
  2174     return Undirector<const Digraph>(digraph);
  2175   }
  2176 
  2177   template <typename _Graph, typename _DirectionMap>
  2178   class OrienterBase {
  2179   public:
  2180 
  2181     typedef _Graph Graph;
  2182     typedef _DirectionMap DirectionMap;
  2183 
  2184     typedef typename Graph::Node Node;
  2185     typedef typename Graph::Edge Arc;
  2186 
  2187     void reverseArc(const Arc& arc) {
  2188       _direction->set(arc, !(*_direction)[arc]);
  2189     }
  2190 
  2191     void first(Node& i) const { _graph->first(i); }
  2192     void first(Arc& i) const { _graph->first(i); }
  2193     void firstIn(Arc& i, const Node& n) const {
  2194       bool d;
  2195       _graph->firstInc(i, d, n);
  2196       while (i != INVALID && d == (*_direction)[i]) _graph->nextInc(i, d);
  2197     }
  2198     void firstOut(Arc& i, const Node& n ) const {
  2199       bool d;
  2200       _graph->firstInc(i, d, n);
  2201       while (i != INVALID && d != (*_direction)[i]) _graph->nextInc(i, d);
  2202     }
  2203 
  2204     void next(Node& i) const { _graph->next(i); }
  2205     void next(Arc& i) const { _graph->next(i); }
  2206     void nextIn(Arc& i) const {
  2207       bool d = !(*_direction)[i];
  2208       _graph->nextInc(i, d);
  2209       while (i != INVALID && d == (*_direction)[i]) _graph->nextInc(i, d);
  2210     }
  2211     void nextOut(Arc& i) const {
  2212       bool d = (*_direction)[i];
  2213       _graph->nextInc(i, d);
  2214       while (i != INVALID && d != (*_direction)[i]) _graph->nextInc(i, d);
  2215     }
  2216 
  2217     Node source(const Arc& e) const {
  2218       return (*_direction)[e] ? _graph->u(e) : _graph->v(e);
  2219     }
  2220     Node target(const Arc& e) const {
  2221       return (*_direction)[e] ? _graph->v(e) : _graph->u(e);
  2222     }
  2223 
  2224     typedef NodeNumTagIndicator<Graph> NodeNumTag;
  2225     int nodeNum() const { return _graph->nodeNum(); }
  2226 
  2227     typedef EdgeNumTagIndicator<Graph> EdgeNumTag;
  2228     int arcNum() const { return _graph->edgeNum(); }
  2229 
  2230     typedef FindEdgeTagIndicator<Graph> FindEdgeTag;
  2231     Arc findArc(const Node& u, const Node& v,
  2232                 const Arc& prev = INVALID) {
  2233       Arc arc = prev;
  2234       bool d = arc == INVALID ? true : (*_direction)[arc];
  2235       if (d) {
  2236         arc = _graph->findEdge(u, v, arc);
  2237         while (arc != INVALID && !(*_direction)[arc]) {
  2238           _graph->findEdge(u, v, arc);
  2239         }
  2240         if (arc != INVALID) return arc;
  2241       }
  2242       _graph->findEdge(v, u, arc);
  2243       while (arc != INVALID && (*_direction)[arc]) {
  2244         _graph->findEdge(u, v, arc);
  2245       }
  2246       return arc;
  2247     }
  2248 
  2249     Node addNode() {
  2250       return Node(_graph->addNode());
  2251     }
  2252 
  2253     Arc addArc(const Node& u, const Node& v) {
  2254       Arc arc = _graph->addArc(u, v);
  2255       _direction->set(arc, _graph->source(arc) == u);
  2256       return arc;
  2257     }
  2258 
  2259     void erase(const Node& i) { _graph->erase(i); }
  2260     void erase(const Arc& i) { _graph->erase(i); }
  2261 
  2262     void clear() { _graph->clear(); }
  2263 
  2264     int id(const Node& v) const { return _graph->id(v); }
  2265     int id(const Arc& e) const { return _graph->id(e); }
  2266 
  2267     Node nodeFromId(int idx) const { return _graph->nodeFromId(idx); }
  2268     Arc arcFromId(int idx) const { return _graph->edgeFromId(idx); }
  2269 
  2270     int maxNodeId() const { return _graph->maxNodeId(); }
  2271     int maxArcId() const { return _graph->maxEdgeId(); }
  2272 
  2273     typedef typename ItemSetTraits<Graph, Node>::ItemNotifier NodeNotifier;
  2274     NodeNotifier& notifier(Node) const { return _graph->notifier(Node()); }
  2275 
  2276     typedef typename ItemSetTraits<Graph, Arc>::ItemNotifier ArcNotifier;
  2277     ArcNotifier& notifier(Arc) const { return _graph->notifier(Arc()); }
  2278 
  2279     template <typename _Value>
  2280     class NodeMap : public _Graph::template NodeMap<_Value> {
  2281     public:
  2282 
  2283       typedef typename _Graph::template NodeMap<_Value> Parent;
  2284 
  2285       explicit NodeMap(const OrienterBase& adapter)
  2286         : Parent(*adapter._graph) {}
  2287 
  2288       NodeMap(const OrienterBase& adapter, const _Value& value)
  2289         : Parent(*adapter._graph, value) {}
  2290 
  2291     private:
  2292       NodeMap& operator=(const NodeMap& cmap) {
  2293         return operator=<NodeMap>(cmap);
  2294       }
  2295 
  2296       template <typename CMap>
  2297       NodeMap& operator=(const CMap& cmap) {
  2298         Parent::operator=(cmap);
  2299         return *this;
  2300       }
  2301 
  2302     };
  2303 
  2304     template <typename _Value>
  2305     class ArcMap : public _Graph::template EdgeMap<_Value> {
  2306     public:
  2307 
  2308       typedef typename Graph::template EdgeMap<_Value> Parent;
  2309 
  2310       explicit ArcMap(const OrienterBase& adapter)
  2311         : Parent(*adapter._graph) { }
  2312 
  2313       ArcMap(const OrienterBase& adapter, const _Value& value)
  2314         : Parent(*adapter._graph, value) { }
  2315 
  2316     private:
  2317       ArcMap& operator=(const ArcMap& cmap) {
  2318         return operator=<ArcMap>(cmap);
  2319       }
  2320 
  2321       template <typename CMap>
  2322       ArcMap& operator=(const CMap& cmap) {
  2323         Parent::operator=(cmap);
  2324         return *this;
  2325       }
  2326     };
  2327 
  2328 
  2329 
  2330   protected:
  2331     Graph* _graph;
  2332     DirectionMap* _direction;
  2333 
  2334     void setDirectionMap(DirectionMap& direction) {
  2335       _direction = &direction;
  2336     }
  2337 
  2338     void setGraph(Graph& graph) {
  2339       _graph = &graph;
  2340     }
  2341 
  2342   };
  2343 
  2344   /// \ingroup graph_adaptors
  2345   ///
  2346   /// \brief Orients the edges of the graph to get a digraph
  2347   ///
  2348   /// This adaptor orients each edge in the undirected graph. The
  2349   /// direction of the arcs stored in an edge node map.  The arcs can
  2350   /// be easily reverted by the \c reverseArc() member function in the
  2351   /// adaptor. The Orienter adaptor is conform to the \ref
  2352   /// concepts::Digraph "Digraph concept".
  2353   ///
  2354   /// \tparam _Graph It must be conform to the \ref concepts::Graph
  2355   /// "Graph concept". The type can be specified to be const.
  2356   /// \tparam _DirectionMap A bool valued edge map of the the adapted
  2357   /// graph.
  2358   ///
  2359   /// \sa orienter
  2360   template<typename _Graph,
  2361            typename DirectionMap = typename _Graph::template EdgeMap<bool> >
  2362   class Orienter :
  2363     public DigraphAdaptorExtender<OrienterBase<_Graph, DirectionMap> > {
  2364   public:
  2365     typedef _Graph Graph;
  2366     typedef DigraphAdaptorExtender<
  2367       OrienterBase<_Graph, DirectionMap> > Parent;
  2368     typedef typename Parent::Arc Arc;
  2369   protected:
  2370     Orienter() { }
  2371   public:
  2372 
  2373     /// \brief Constructor of the adaptor
  2374     ///
  2375     /// Constructor of the adaptor
  2376     Orienter(Graph& graph, DirectionMap& direction) {
  2377       setGraph(graph);
  2378       setDirectionMap(direction);
  2379     }
  2380 
  2381     /// \brief Reverse arc
  2382     ///
  2383     /// It reverse the given arc. It simply negate the direction in the map.
  2384     void reverseArc(const Arc& a) {
  2385       Parent::reverseArc(a);
  2386     }
  2387   };
  2388 
  2389   /// \brief Just gives back a Orienter
  2390   ///
  2391   /// Just gives back a Orienter
  2392   template<typename Graph, typename DirectionMap>
  2393   Orienter<const Graph, DirectionMap>
  2394   orienter(const Graph& graph, DirectionMap& dm) {
  2395     return Orienter<const Graph, DirectionMap>(graph, dm);
  2396   }
  2397 
  2398   template<typename Graph, typename DirectionMap>
  2399   Orienter<const Graph, const DirectionMap>
  2400   orienter(const Graph& graph, const DirectionMap& dm) {
  2401     return Orienter<const Graph, const DirectionMap>(graph, dm);
  2402   }
  2403 
  2404   namespace _adaptor_bits {
  2405 
  2406     template<typename _Digraph,
  2407              typename _CapacityMap = typename _Digraph::template ArcMap<int>,
  2408              typename _FlowMap = _CapacityMap,
  2409              typename _Tolerance = Tolerance<typename _CapacityMap::Value> >
  2410     class ResForwardFilter {
  2411     public:
  2412 
  2413       typedef _Digraph Digraph;
  2414       typedef _CapacityMap CapacityMap;
  2415       typedef _FlowMap FlowMap;
  2416       typedef _Tolerance Tolerance;
  2417 
  2418       typedef typename Digraph::Arc Key;
  2419       typedef bool Value;
  2420 
  2421     private:
  2422 
  2423       const CapacityMap* _capacity;
  2424       const FlowMap* _flow;
  2425       Tolerance _tolerance;
  2426     public:
  2427 
  2428       ResForwardFilter(const CapacityMap& capacity, const FlowMap& flow,
  2429                        const Tolerance& tolerance = Tolerance())
  2430         : _capacity(&capacity), _flow(&flow), _tolerance(tolerance) { }
  2431 
  2432       bool operator[](const typename Digraph::Arc& a) const {
  2433         return _tolerance.positive((*_capacity)[a] - (*_flow)[a]);
  2434       }
  2435     };
  2436 
  2437     template<typename _Digraph,
  2438              typename _CapacityMap = typename _Digraph::template ArcMap<int>,
  2439              typename _FlowMap = _CapacityMap,
  2440              typename _Tolerance = Tolerance<typename _CapacityMap::Value> >
  2441     class ResBackwardFilter {
  2442     public:
  2443 
  2444       typedef _Digraph Digraph;
  2445       typedef _CapacityMap CapacityMap;
  2446       typedef _FlowMap FlowMap;
  2447       typedef _Tolerance Tolerance;
  2448 
  2449       typedef typename Digraph::Arc Key;
  2450       typedef bool Value;
  2451 
  2452     private:
  2453 
  2454       const CapacityMap* _capacity;
  2455       const FlowMap* _flow;
  2456       Tolerance _tolerance;
  2457 
  2458     public:
  2459 
  2460       ResBackwardFilter(const CapacityMap& capacity, const FlowMap& flow,
  2461                         const Tolerance& tolerance = Tolerance())
  2462         : _capacity(&capacity), _flow(&flow), _tolerance(tolerance) { }
  2463 
  2464       bool operator[](const typename Digraph::Arc& a) const {
  2465         return _tolerance.positive((*_flow)[a]);
  2466       }
  2467     };
  2468 
  2469   }
  2470 
  2471   /// \ingroup graph_adaptors
  2472   ///
  2473   /// \brief An adaptor for composing the residual graph for directed
  2474   /// flow and circulation problems.
  2475   ///
  2476   /// An adaptor for composing the residual graph for directed flow and
  2477   /// circulation problems.  Let \f$ G=(V, A) \f$ be a directed graph
  2478   /// and let \f$ F \f$ be a number type. Let moreover \f$ f,c:A\to F \f$,
  2479   /// be functions on the arc-set.
  2480   ///
  2481   /// Then Residual implements the digraph structure with
  2482   /// node-set \f$ V \f$ and arc-set \f$ A_{forward}\cup A_{backward} \f$,
  2483   /// where \f$ A_{forward}=\{uv : uv\in A, f(uv)<c(uv)\} \f$ and
  2484   /// \f$ A_{backward}=\{vu : uv\in A, f(uv)>0\} \f$, i.e. the so
  2485   /// called residual graph.  When we take the union
  2486   /// \f$ A_{forward}\cup A_{backward} \f$, multiplicities are counted,
  2487   /// i.e.  if an arc is in both \f$ A_{forward} \f$ and
  2488   /// \f$ A_{backward} \f$, then in the adaptor it appears in both
  2489   /// orientation.
  2490   ///
  2491   /// \tparam _Digraph It must be conform to the \ref concepts::Digraph
  2492   /// "Digraph concept". The type is implicitly const.
  2493   /// \tparam _CapacityMap An arc map of some numeric type, it defines
  2494   /// the capacities in the flow problem. The map is implicitly const.
  2495   /// \tparam _FlowMap An arc map of some numeric type, it defines
  2496   /// the capacities in the flow problem.
  2497   /// \tparam _Tolerance Handler for inexact computation.
  2498   template<typename _Digraph,
  2499            typename _CapacityMap = typename _Digraph::template ArcMap<int>,
  2500            typename _FlowMap = _CapacityMap,
  2501            typename _Tolerance = Tolerance<typename _CapacityMap::Value> >
  2502   class Residual :
  2503     public FilterArcs<
  2504     Undirector<const _Digraph>,
  2505     typename Undirector<const _Digraph>::template CombinedArcMap<
  2506       _adaptor_bits::ResForwardFilter<const _Digraph, _CapacityMap,
  2507                                       _FlowMap, _Tolerance>,
  2508       _adaptor_bits::ResBackwardFilter<const _Digraph, _CapacityMap,
  2509                                        _FlowMap, _Tolerance> > >
  2510   {
  2511   public:
  2512 
  2513     typedef _Digraph Digraph;
  2514     typedef _CapacityMap CapacityMap;
  2515     typedef _FlowMap FlowMap;
  2516     typedef _Tolerance Tolerance;
  2517 
  2518     typedef typename CapacityMap::Value Value;
  2519     typedef Residual Adaptor;
  2520 
  2521   protected:
  2522 
  2523     typedef Undirector<const Digraph> Undirected;
  2524 
  2525     typedef _adaptor_bits::ResForwardFilter<const Digraph, CapacityMap,
  2526                                             FlowMap, Tolerance> ForwardFilter;
  2527 
  2528     typedef _adaptor_bits::ResBackwardFilter<const Digraph, CapacityMap,
  2529                                              FlowMap, Tolerance> BackwardFilter;
  2530 
  2531     typedef typename Undirected::
  2532     template CombinedArcMap<ForwardFilter, BackwardFilter> ArcFilter;
  2533 
  2534     typedef FilterArcs<Undirected, ArcFilter> Parent;
  2535 
  2536     const CapacityMap* _capacity;
  2537     FlowMap* _flow;
  2538 
  2539     Undirected _graph;
  2540     ForwardFilter _forward_filter;
  2541     BackwardFilter _backward_filter;
  2542     ArcFilter _arc_filter;
  2543 
  2544   public:
  2545 
  2546     /// \brief Constructor of the residual digraph.
  2547     ///
  2548     /// Constructor of the residual graph. The parameters are the digraph,
  2549     /// the flow map, the capacity map and a tolerance object.
  2550     Residual(const Digraph& digraph, const CapacityMap& capacity,
  2551              FlowMap& flow, const Tolerance& tolerance = Tolerance())
  2552       : Parent(), _capacity(&capacity), _flow(&flow), _graph(digraph),
  2553         _forward_filter(capacity, flow, tolerance),
  2554         _backward_filter(capacity, flow, tolerance),
  2555         _arc_filter(_forward_filter, _backward_filter)
  2556     {
  2557       Parent::setDigraph(_graph);
  2558       Parent::setArcFilterMap(_arc_filter);
  2559     }
  2560 
  2561     typedef typename Parent::Arc Arc;
  2562 
  2563     /// \brief Gives back the residual capacity of the arc.
  2564     ///
  2565     /// Gives back the residual capacity of the arc.
  2566     Value residualCapacity(const Arc& a) const {
  2567       if (Undirected::direction(a)) {
  2568         return (*_capacity)[a] - (*_flow)[a];
  2569       } else {
  2570         return (*_flow)[a];
  2571       }
  2572     }
  2573 
  2574     /// \brief Augment on the given arc in the residual graph.
  2575     ///
  2576     /// Augment on the given arc in the residual graph. It increase
  2577     /// or decrease the flow on the original arc depend on the direction
  2578     /// of the residual arc.
  2579     void augment(const Arc& a, const Value& v) const {
  2580       if (Undirected::direction(a)) {
  2581         _flow->set(a, (*_flow)[a] + v);
  2582       } else {
  2583         _flow->set(a, (*_flow)[a] - v);
  2584       }
  2585     }
  2586 
  2587     /// \brief Returns the direction of the arc.
  2588     ///
  2589     /// Returns true when the arc is same oriented as the original arc.
  2590     static bool forward(const Arc& a) {
  2591       return Undirected::direction(a);
  2592     }
  2593 
  2594     /// \brief Returns the direction of the arc.
  2595     ///
  2596     /// Returns true when the arc is opposite oriented as the original arc.
  2597     static bool backward(const Arc& a) {
  2598       return !Undirected::direction(a);
  2599     }
  2600 
  2601     /// \brief Gives back the forward oriented residual arc.
  2602     ///
  2603     /// Gives back the forward oriented residual arc.
  2604     static Arc forward(const typename Digraph::Arc& a) {
  2605       return Undirected::direct(a, true);
  2606     }
  2607 
  2608     /// \brief Gives back the backward oriented residual arc.
  2609     ///
  2610     /// Gives back the backward oriented residual arc.
  2611     static Arc backward(const typename Digraph::Arc& a) {
  2612       return Undirected::direct(a, false);
  2613     }
  2614 
  2615     /// \brief Residual capacity map.
  2616     ///
  2617     /// In generic residual graph the residual capacity can be obtained
  2618     /// as a map.
  2619     class ResidualCapacity {
  2620     protected:
  2621       const Adaptor* _adaptor;
  2622     public:
  2623       /// The Key type
  2624       typedef Arc Key;
  2625       /// The Value type
  2626       typedef typename _CapacityMap::Value Value;
  2627 
  2628       /// Constructor
  2629       ResidualCapacity(const Adaptor& adaptor) : _adaptor(&adaptor) {}
  2630 
  2631       /// \e
  2632       Value operator[](const Arc& a) const {
  2633         return _adaptor->residualCapacity(a);
  2634       }
  2635 
  2636     };
  2637 
  2638   };
  2639 
  2640   template <typename _Digraph>
  2641   class SplitNodesBase {
  2642   public:
  2643 
  2644     typedef _Digraph Digraph;
  2645     typedef DigraphAdaptorBase<const _Digraph> Parent;
  2646     typedef SplitNodesBase Adaptor;
  2647 
  2648     typedef typename Digraph::Node DigraphNode;
  2649     typedef typename Digraph::Arc DigraphArc;
  2650 
  2651     class Node;
  2652     class Arc;
  2653 
  2654   private:
  2655 
  2656     template <typename T> class NodeMapBase;
  2657     template <typename T> class ArcMapBase;
  2658 
  2659   public:
  2660 
  2661     class Node : public DigraphNode {
  2662       friend class SplitNodesBase;
  2663       template <typename T> friend class NodeMapBase;
  2664     private:
  2665 
  2666       bool _in;
  2667       Node(DigraphNode node, bool in)
  2668         : DigraphNode(node), _in(in) {}
  2669 
  2670     public:
  2671 
  2672       Node() {}
  2673       Node(Invalid) : DigraphNode(INVALID), _in(true) {}
  2674 
  2675       bool operator==(const Node& node) const {
  2676         return DigraphNode::operator==(node) && _in == node._in;
  2677       }
  2678 
  2679       bool operator!=(const Node& node) const {
  2680         return !(*this == node);
  2681       }
  2682 
  2683       bool operator<(const Node& node) const {
  2684         return DigraphNode::operator<(node) ||
  2685           (DigraphNode::operator==(node) && _in < node._in);
  2686       }
  2687     };
  2688 
  2689     class Arc {
  2690       friend class SplitNodesBase;
  2691       template <typename T> friend class ArcMapBase;
  2692     private:
  2693       typedef BiVariant<DigraphArc, DigraphNode> ArcImpl;
  2694 
  2695       explicit Arc(const DigraphArc& arc) : _item(arc) {}
  2696       explicit Arc(const DigraphNode& node) : _item(node) {}
  2697 
  2698       ArcImpl _item;
  2699 
  2700     public:
  2701       Arc() {}
  2702       Arc(Invalid) : _item(DigraphArc(INVALID)) {}
  2703 
  2704       bool operator==(const Arc& arc) const {
  2705         if (_item.firstState()) {
  2706           if (arc._item.firstState()) {
  2707             return _item.first() == arc._item.first();
  2708           }
  2709         } else {
  2710           if (arc._item.secondState()) {
  2711             return _item.second() == arc._item.second();
  2712           }
  2713         }
  2714         return false;
  2715       }
  2716 
  2717       bool operator!=(const Arc& arc) const {
  2718         return !(*this == arc);
  2719       }
  2720 
  2721       bool operator<(const Arc& arc) const {
  2722         if (_item.firstState()) {
  2723           if (arc._item.firstState()) {
  2724             return _item.first() < arc._item.first();
  2725           }
  2726           return false;
  2727         } else {
  2728           if (arc._item.secondState()) {
  2729             return _item.second() < arc._item.second();
  2730           }
  2731           return true;
  2732         }
  2733       }
  2734 
  2735       operator DigraphArc() const { return _item.first(); }
  2736       operator DigraphNode() const { return _item.second(); }
  2737 
  2738     };
  2739 
  2740     void first(Node& n) const {
  2741       _digraph->first(n);
  2742       n._in = true;
  2743     }
  2744 
  2745     void next(Node& n) const {
  2746       if (n._in) {
  2747         n._in = false;
  2748       } else {
  2749         n._in = true;
  2750         _digraph->next(n);
  2751       }
  2752     }
  2753 
  2754     void first(Arc& e) const {
  2755       e._item.setSecond();
  2756       _digraph->first(e._item.second());
  2757       if (e._item.second() == INVALID) {
  2758         e._item.setFirst();
  2759         _digraph->first(e._item.first());
  2760       }
  2761     }
  2762 
  2763     void next(Arc& e) const {
  2764       if (e._item.secondState()) {
  2765         _digraph->next(e._item.second());
  2766         if (e._item.second() == INVALID) {
  2767           e._item.setFirst();
  2768           _digraph->first(e._item.first());
  2769         }
  2770       } else {
  2771         _digraph->next(e._item.first());
  2772       }
  2773     }
  2774 
  2775     void firstOut(Arc& e, const Node& n) const {
  2776       if (n._in) {
  2777         e._item.setSecond(n);
  2778       } else {
  2779         e._item.setFirst();
  2780         _digraph->firstOut(e._item.first(), n);
  2781       }
  2782     }
  2783 
  2784     void nextOut(Arc& e) const {
  2785       if (!e._item.firstState()) {
  2786         e._item.setFirst(INVALID);
  2787       } else {
  2788         _digraph->nextOut(e._item.first());
  2789       }
  2790     }
  2791 
  2792     void firstIn(Arc& e, const Node& n) const {
  2793       if (!n._in) {
  2794         e._item.setSecond(n);
  2795       } else {
  2796         e._item.setFirst();
  2797         _digraph->firstIn(e._item.first(), n);
  2798       }
  2799     }
  2800 
  2801     void nextIn(Arc& e) const {
  2802       if (!e._item.firstState()) {
  2803         e._item.setFirst(INVALID);
  2804       } else {
  2805         _digraph->nextIn(e._item.first());
  2806       }
  2807     }
  2808 
  2809     Node source(const Arc& e) const {
  2810       if (e._item.firstState()) {
  2811         return Node(_digraph->source(e._item.first()), false);
  2812       } else {
  2813         return Node(e._item.second(), true);
  2814       }
  2815     }
  2816 
  2817     Node target(const Arc& e) const {
  2818       if (e._item.firstState()) {
  2819         return Node(_digraph->target(e._item.first()), true);
  2820       } else {
  2821         return Node(e._item.second(), false);
  2822       }
  2823     }
  2824 
  2825     int id(const Node& n) const {
  2826       return (_digraph->id(n) << 1) | (n._in ? 0 : 1);
  2827     }
  2828     Node nodeFromId(int ix) const {
  2829       return Node(_digraph->nodeFromId(ix >> 1), (ix & 1) == 0);
  2830     }
  2831     int maxNodeId() const {
  2832       return 2 * _digraph->maxNodeId() + 1;
  2833     }
  2834 
  2835     int id(const Arc& e) const {
  2836       if (e._item.firstState()) {
  2837         return _digraph->id(e._item.first()) << 1;
  2838       } else {
  2839         return (_digraph->id(e._item.second()) << 1) | 1;
  2840       }
  2841     }
  2842     Arc arcFromId(int ix) const {
  2843       if ((ix & 1) == 0) {
  2844         return Arc(_digraph->arcFromId(ix >> 1));
  2845       } else {
  2846         return Arc(_digraph->nodeFromId(ix >> 1));
  2847       }
  2848     }
  2849     int maxArcId() const {
  2850       return std::max(_digraph->maxNodeId() << 1,
  2851                       (_digraph->maxArcId() << 1) | 1);
  2852     }
  2853 
  2854     static bool inNode(const Node& n) {
  2855       return n._in;
  2856     }
  2857 
  2858     static bool outNode(const Node& n) {
  2859       return !n._in;
  2860     }
  2861 
  2862     static bool origArc(const Arc& e) {
  2863       return e._item.firstState();
  2864     }
  2865 
  2866     static bool bindArc(const Arc& e) {
  2867       return e._item.secondState();
  2868     }
  2869 
  2870     static Node inNode(const DigraphNode& n) {
  2871       return Node(n, true);
  2872     }
  2873 
  2874     static Node outNode(const DigraphNode& n) {
  2875       return Node(n, false);
  2876     }
  2877 
  2878     static Arc arc(const DigraphNode& n) {
  2879       return Arc(n);
  2880     }
  2881 
  2882     static Arc arc(const DigraphArc& e) {
  2883       return Arc(e);
  2884     }
  2885 
  2886     typedef True NodeNumTag;
  2887 
  2888     int nodeNum() const {
  2889       return  2 * countNodes(*_digraph);
  2890     }
  2891 
  2892     typedef True EdgeNumTag;
  2893     int arcNum() const {
  2894       return countArcs(*_digraph) + countNodes(*_digraph);
  2895     }
  2896 
  2897     typedef True FindEdgeTag;
  2898     Arc findArc(const Node& u, const Node& v,
  2899                 const Arc& prev = INVALID) const {
  2900       if (inNode(u)) {
  2901         if (outNode(v)) {
  2902           if (static_cast<const DigraphNode&>(u) ==
  2903               static_cast<const DigraphNode&>(v) && prev == INVALID) {
  2904             return Arc(u);
  2905           }
  2906         }
  2907       } else {
  2908         if (inNode(v)) {
  2909           return Arc(::lemon::findArc(*_digraph, u, v, prev));
  2910         }
  2911       }
  2912       return INVALID;
  2913     }
  2914 
  2915   private:
  2916 
  2917     template <typename _Value>
  2918     class NodeMapBase
  2919       : public MapTraits<typename Parent::template NodeMap<_Value> > {
  2920       typedef typename Parent::template NodeMap<_Value> NodeImpl;
  2921     public:
  2922       typedef Node Key;
  2923       typedef _Value Value;
  2924 
  2925       NodeMapBase(const Adaptor& adaptor)
  2926         : _in_map(*adaptor._digraph), _out_map(*adaptor._digraph) {}
  2927       NodeMapBase(const Adaptor& adaptor, const Value& value)
  2928         : _in_map(*adaptor._digraph, value),
  2929           _out_map(*adaptor._digraph, value) {}
  2930 
  2931       void set(const Node& key, const Value& val) {
  2932         if (Adaptor::inNode(key)) { _in_map.set(key, val); }
  2933         else {_out_map.set(key, val); }
  2934       }
  2935 
  2936       typename MapTraits<NodeImpl>::ReturnValue
  2937       operator[](const Node& key) {
  2938         if (Adaptor::inNode(key)) { return _in_map[key]; }
  2939         else { return _out_map[key]; }
  2940       }
  2941 
  2942       typename MapTraits<NodeImpl>::ConstReturnValue
  2943       operator[](const Node& key) const {
  2944         if (Adaptor::inNode(key)) { return _in_map[key]; }
  2945         else { return _out_map[key]; }
  2946       }
  2947 
  2948     private:
  2949       NodeImpl _in_map, _out_map;
  2950     };
  2951 
  2952     template <typename _Value>
  2953     class ArcMapBase
  2954       : public MapTraits<typename Parent::template ArcMap<_Value> > {
  2955       typedef typename Parent::template ArcMap<_Value> ArcImpl;
  2956       typedef typename Parent::template NodeMap<_Value> NodeImpl;
  2957     public:
  2958       typedef Arc Key;
  2959       typedef _Value Value;
  2960 
  2961       ArcMapBase(const Adaptor& adaptor)
  2962         : _arc_map(*adaptor._digraph), _node_map(*adaptor._digraph) {}
  2963       ArcMapBase(const Adaptor& adaptor, const Value& value)
  2964         : _arc_map(*adaptor._digraph, value),
  2965           _node_map(*adaptor._digraph, value) {}
  2966 
  2967       void set(const Arc& key, const Value& val) {
  2968         if (Adaptor::origArc(key)) {
  2969           _arc_map.set(key._item.first(), val);
  2970         } else {
  2971           _node_map.set(key._item.second(), val);
  2972         }
  2973       }
  2974 
  2975       typename MapTraits<ArcImpl>::ReturnValue
  2976       operator[](const Arc& key) {
  2977         if (Adaptor::origArc(key)) {
  2978           return _arc_map[key._item.first()];
  2979         } else {
  2980           return _node_map[key._item.second()];
  2981         }
  2982       }
  2983 
  2984       typename MapTraits<ArcImpl>::ConstReturnValue
  2985       operator[](const Arc& key) const {
  2986         if (Adaptor::origArc(key)) {
  2987           return _arc_map[key._item.first()];
  2988         } else {
  2989           return _node_map[key._item.second()];
  2990         }
  2991       }
  2992 
  2993     private:
  2994       ArcImpl _arc_map;
  2995       NodeImpl _node_map;
  2996     };
  2997 
  2998   public:
  2999 
  3000     template <typename _Value>
  3001     class NodeMap
  3002       : public SubMapExtender<Adaptor, NodeMapBase<_Value> >
  3003     {
  3004     public:
  3005       typedef _Value Value;
  3006       typedef SubMapExtender<Adaptor, NodeMapBase<Value> > Parent;
  3007 
  3008       NodeMap(const Adaptor& adaptor)
  3009         : Parent(adaptor) {}
  3010 
  3011       NodeMap(const Adaptor& adaptor, const Value& value)
  3012         : Parent(adaptor, value) {}
  3013 
  3014     private:
  3015       NodeMap& operator=(const NodeMap& cmap) {
  3016         return operator=<NodeMap>(cmap);
  3017       }
  3018 
  3019       template <typename CMap>
  3020       NodeMap& operator=(const CMap& cmap) {
  3021         Parent::operator=(cmap);
  3022         return *this;
  3023       }
  3024     };
  3025 
  3026     template <typename _Value>
  3027     class ArcMap
  3028       : public SubMapExtender<Adaptor, ArcMapBase<_Value> >
  3029     {
  3030     public:
  3031       typedef _Value Value;
  3032       typedef SubMapExtender<Adaptor, ArcMapBase<Value> > Parent;
  3033 
  3034       ArcMap(const Adaptor& adaptor)
  3035         : Parent(adaptor) {}
  3036 
  3037       ArcMap(const Adaptor& adaptor, const Value& value)
  3038         : Parent(adaptor, value) {}
  3039 
  3040     private:
  3041       ArcMap& operator=(const ArcMap& cmap) {
  3042         return operator=<ArcMap>(cmap);
  3043       }
  3044 
  3045       template <typename CMap>
  3046       ArcMap& operator=(const CMap& cmap) {
  3047         Parent::operator=(cmap);
  3048         return *this;
  3049       }
  3050     };
  3051 
  3052   protected:
  3053 
  3054     SplitNodesBase() : _digraph(0) {}
  3055 
  3056     Digraph* _digraph;
  3057 
  3058     void setDigraph(Digraph& digraph) {
  3059       _digraph = &digraph;
  3060     }
  3061 
  3062   };
  3063 
  3064   /// \ingroup graph_adaptors
  3065   ///
  3066   /// \brief Split the nodes of a directed graph
  3067   ///
  3068   /// The SplitNodes adaptor splits each node into an in-node and an
  3069   /// out-node. Formaly, the adaptor replaces each \f$ u \f$ node in
  3070   /// the digraph with two nodes(namely node \f$ u_{in} \f$ and node
  3071   /// \f$ u_{out} \f$). If there is a \f$ (v, u) \f$ arc in the
  3072   /// original digraph the new target of the arc will be \f$ u_{in} \f$
  3073   /// and similarly the source of the original \f$ (u, v) \f$ arc
  3074   /// will be \f$ u_{out} \f$.  The adaptor will add for each node in
  3075   /// the original digraph an additional arc which connects
  3076   /// \f$ (u_{in}, u_{out}) \f$.
  3077   ///
  3078   /// The aim of this class is to run algorithm with node costs if the
  3079   /// algorithm can use directly just arc costs. In this case we should use
  3080   /// a \c SplitNodes and set the node cost of the graph to the
  3081   /// bind arc in the adapted graph.
  3082   ///
  3083   /// \tparam _Digraph It must be conform to the \ref concepts::Digraph
  3084   /// "Digraph concept". The type can be specified to be const.
  3085   template <typename _Digraph>
  3086   class SplitNodes
  3087     : public DigraphAdaptorExtender<SplitNodesBase<_Digraph> > {
  3088   public:
  3089     typedef _Digraph Digraph;
  3090     typedef DigraphAdaptorExtender<SplitNodesBase<Digraph> > Parent;
  3091 
  3092     typedef typename Digraph::Node DigraphNode;
  3093     typedef typename Digraph::Arc DigraphArc;
  3094 
  3095     typedef typename Parent::Node Node;
  3096     typedef typename Parent::Arc Arc;
  3097 
  3098     /// \brief Constructor of the adaptor.
  3099     ///
  3100     /// Constructor of the adaptor.
  3101     SplitNodes(Digraph& g) {
  3102       Parent::setDigraph(g);
  3103     }
  3104 
  3105     /// \brief Returns true when the node is in-node.
  3106     ///
  3107     /// Returns true when the node is in-node.
  3108     static bool inNode(const Node& n) {
  3109       return Parent::inNode(n);
  3110     }
  3111 
  3112     /// \brief Returns true when the node is out-node.
  3113     ///
  3114     /// Returns true when the node is out-node.
  3115     static bool outNode(const Node& n) {
  3116       return Parent::outNode(n);
  3117     }
  3118 
  3119     /// \brief Returns true when the arc is arc in the original digraph.
  3120     ///
  3121     /// Returns true when the arc is arc in the original digraph.
  3122     static bool origArc(const Arc& a) {
  3123       return Parent::origArc(a);
  3124     }
  3125 
  3126     /// \brief Returns true when the arc binds an in-node and an out-node.
  3127     ///
  3128     /// Returns true when the arc binds an in-node and an out-node.
  3129     static bool bindArc(const Arc& a) {
  3130       return Parent::bindArc(a);
  3131     }
  3132 
  3133     /// \brief Gives back the in-node created from the \c node.
  3134     ///
  3135     /// Gives back the in-node created from the \c node.
  3136     static Node inNode(const DigraphNode& n) {
  3137       return Parent::inNode(n);
  3138     }
  3139 
  3140     /// \brief Gives back the out-node created from the \c node.
  3141     ///
  3142     /// Gives back the out-node created from the \c node.
  3143     static Node outNode(const DigraphNode& n) {
  3144       return Parent::outNode(n);
  3145     }
  3146 
  3147     /// \brief Gives back the arc binds the two part of the node.
  3148     ///
  3149     /// Gives back the arc binds the two part of the node.
  3150     static Arc arc(const DigraphNode& n) {
  3151       return Parent::arc(n);
  3152     }
  3153 
  3154     /// \brief Gives back the arc of the original arc.
  3155     ///
  3156     /// Gives back the arc of the original arc.
  3157     static Arc arc(const DigraphArc& a) {
  3158       return Parent::arc(a);
  3159     }
  3160 
  3161     /// \brief NodeMap combined from two original NodeMap
  3162     ///
  3163     /// This class adapt two of the original digraph NodeMap to
  3164     /// get a node map on the adapted digraph.
  3165     template <typename InNodeMap, typename OutNodeMap>
  3166     class CombinedNodeMap {
  3167     public:
  3168 
  3169       typedef Node Key;
  3170       typedef typename InNodeMap::Value Value;
  3171 
  3172       /// \brief Constructor
  3173       ///
  3174       /// Constructor.
  3175       CombinedNodeMap(InNodeMap& in_map, OutNodeMap& out_map)
  3176         : _in_map(in_map), _out_map(out_map) {}
  3177 
  3178       /// \brief The subscript operator.
  3179       ///
  3180       /// The subscript operator.
  3181       Value& operator[](const Key& key) {
  3182         if (Parent::inNode(key)) {
  3183           return _in_map[key];
  3184         } else {
  3185           return _out_map[key];
  3186         }
  3187       }
  3188 
  3189       /// \brief The const subscript operator.
  3190       ///
  3191       /// The const subscript operator.
  3192       Value operator[](const Key& key) const {
  3193         if (Parent::inNode(key)) {
  3194           return _in_map[key];
  3195         } else {
  3196           return _out_map[key];
  3197         }
  3198       }
  3199 
  3200       /// \brief The setter function of the map.
  3201       ///
  3202       /// The setter function of the map.
  3203       void set(const Key& key, const Value& value) {
  3204         if (Parent::inNode(key)) {
  3205           _in_map.set(key, value);
  3206         } else {
  3207           _out_map.set(key, value);
  3208         }
  3209       }
  3210 
  3211     private:
  3212 
  3213       InNodeMap& _in_map;
  3214       OutNodeMap& _out_map;
  3215 
  3216     };
  3217 
  3218 
  3219     /// \brief Just gives back a combined node map
  3220     ///
  3221     /// Just gives back a combined node map
  3222     template <typename InNodeMap, typename OutNodeMap>
  3223     static CombinedNodeMap<InNodeMap, OutNodeMap>
  3224     combinedNodeMap(InNodeMap& in_map, OutNodeMap& out_map) {
  3225       return CombinedNodeMap<InNodeMap, OutNodeMap>(in_map, out_map);
  3226     }
  3227 
  3228     template <typename InNodeMap, typename OutNodeMap>
  3229     static CombinedNodeMap<const InNodeMap, OutNodeMap>
  3230     combinedNodeMap(const InNodeMap& in_map, OutNodeMap& out_map) {
  3231       return CombinedNodeMap<const InNodeMap, OutNodeMap>(in_map, out_map);
  3232     }
  3233 
  3234     template <typename InNodeMap, typename OutNodeMap>
  3235     static CombinedNodeMap<InNodeMap, const OutNodeMap>
  3236     combinedNodeMap(InNodeMap& in_map, const OutNodeMap& out_map) {
  3237       return CombinedNodeMap<InNodeMap, const OutNodeMap>(in_map, out_map);
  3238     }
  3239 
  3240     template <typename InNodeMap, typename OutNodeMap>
  3241     static CombinedNodeMap<const InNodeMap, const OutNodeMap>
  3242     combinedNodeMap(const InNodeMap& in_map, const OutNodeMap& out_map) {
  3243       return CombinedNodeMap<const InNodeMap,
  3244         const OutNodeMap>(in_map, out_map);
  3245     }
  3246 
  3247     /// \brief ArcMap combined from an original ArcMap and a NodeMap
  3248     ///
  3249     /// This class adapt an original ArcMap and a NodeMap to get an
  3250     /// arc map on the adapted digraph
  3251     template <typename DigraphArcMap, typename DigraphNodeMap>
  3252     class CombinedArcMap {
  3253     public:
  3254 
  3255       typedef Arc Key;
  3256       typedef typename DigraphArcMap::Value Value;
  3257 
  3258       /// \brief Constructor
  3259       ///
  3260       /// Constructor.
  3261       CombinedArcMap(DigraphArcMap& arc_map, DigraphNodeMap& node_map)
  3262         : _arc_map(arc_map), _node_map(node_map) {}
  3263 
  3264       /// \brief The subscript operator.
  3265       ///
  3266       /// The subscript operator.
  3267       void set(const Arc& arc, const Value& val) {
  3268         if (Parent::origArc(arc)) {
  3269           _arc_map.set(arc, val);
  3270         } else {
  3271           _node_map.set(arc, val);
  3272         }
  3273       }
  3274 
  3275       /// \brief The const subscript operator.
  3276       ///
  3277       /// The const subscript operator.
  3278       Value operator[](const Key& arc) const {
  3279         if (Parent::origArc(arc)) {
  3280           return _arc_map[arc];
  3281         } else {
  3282           return _node_map[arc];
  3283         }
  3284       }
  3285 
  3286       /// \brief The const subscript operator.
  3287       ///
  3288       /// The const subscript operator.
  3289       Value& operator[](const Key& arc) {
  3290         if (Parent::origArc(arc)) {
  3291           return _arc_map[arc];
  3292         } else {
  3293           return _node_map[arc];
  3294         }
  3295       }
  3296 
  3297     private:
  3298       DigraphArcMap& _arc_map;
  3299       DigraphNodeMap& _node_map;
  3300     };
  3301 
  3302     /// \brief Just gives back a combined arc map
  3303     ///
  3304     /// Just gives back a combined arc map
  3305     template <typename DigraphArcMap, typename DigraphNodeMap>
  3306     static CombinedArcMap<DigraphArcMap, DigraphNodeMap>
  3307     combinedArcMap(DigraphArcMap& arc_map, DigraphNodeMap& node_map) {
  3308       return CombinedArcMap<DigraphArcMap, DigraphNodeMap>(arc_map, node_map);
  3309     }
  3310 
  3311     template <typename DigraphArcMap, typename DigraphNodeMap>
  3312     static CombinedArcMap<const DigraphArcMap, DigraphNodeMap>
  3313     combinedArcMap(const DigraphArcMap& arc_map, DigraphNodeMap& node_map) {
  3314       return CombinedArcMap<const DigraphArcMap,
  3315         DigraphNodeMap>(arc_map, node_map);
  3316     }
  3317 
  3318     template <typename DigraphArcMap, typename DigraphNodeMap>
  3319     static CombinedArcMap<DigraphArcMap, const DigraphNodeMap>
  3320     combinedArcMap(DigraphArcMap& arc_map, const DigraphNodeMap& node_map) {
  3321       return CombinedArcMap<DigraphArcMap,
  3322         const DigraphNodeMap>(arc_map, node_map);
  3323     }
  3324 
  3325     template <typename DigraphArcMap, typename DigraphNodeMap>
  3326     static CombinedArcMap<const DigraphArcMap, const DigraphNodeMap>
  3327     combinedArcMap(const DigraphArcMap& arc_map,
  3328                    const DigraphNodeMap& node_map) {
  3329       return CombinedArcMap<const DigraphArcMap,
  3330         const DigraphNodeMap>(arc_map, node_map);
  3331     }
  3332 
  3333   };
  3334 
  3335   /// \brief Just gives back a node splitter
  3336   ///
  3337   /// Just gives back a node splitter
  3338   template<typename Digraph>
  3339   SplitNodes<Digraph>
  3340   splitNodes(const Digraph& digraph) {
  3341     return SplitNodes<Digraph>(digraph);
  3342   }
  3343 
  3344 
  3345 } //namespace lemon
  3346 
  3347 #endif //LEMON_ADAPTORS_H