lemon/digraph_adaptor.h
changeset 430 05357da973ce
child 431 4b6112235fad
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/lemon/digraph_adaptor.h	Sun Nov 30 18:57:18 2008 +0100
     1.3 @@ -0,0 +1,2530 @@
     1.4 +/* -*- C++ -*-
     1.5 + *
     1.6 + * This file is a part of LEMON, a generic C++ optimization library
     1.7 + *
     1.8 + * Copyright (C) 2003-2008
     1.9 + * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
    1.10 + * (Egervary Research Group on Combinatorial Optimization, EGRES).
    1.11 + *
    1.12 + * Permission to use, modify and distribute this software is granted
    1.13 + * provided that this copyright notice appears in all copies. For
    1.14 + * precise terms see the accompanying LICENSE file.
    1.15 + *
    1.16 + * This software is provided "AS IS" with no warranty of any kind,
    1.17 + * express or implied, and with no claim as to its suitability for any
    1.18 + * purpose.
    1.19 + *
    1.20 + */
    1.21 +
    1.22 +#ifndef LEMON_DIGRAPH_ADAPTOR_H
    1.23 +#define LEMON_DIGRAPH_ADAPTOR_H
    1.24 +
    1.25 +///\ingroup graph_adaptors
    1.26 +///\file
    1.27 +///\brief Several digraph adaptors.
    1.28 +///
    1.29 +///This file contains several useful digraph adaptor functions.
    1.30 +
    1.31 +#include <lemon/core.h>
    1.32 +#include <lemon/maps.h>
    1.33 +#include <lemon/bits/variant.h>
    1.34 +
    1.35 +#include <lemon/bits/base_extender.h>
    1.36 +#include <lemon/bits/graph_adaptor_extender.h>
    1.37 +#include <lemon/bits/graph_extender.h>
    1.38 +#include <lemon/tolerance.h>
    1.39 +
    1.40 +#include <algorithm>
    1.41 +
    1.42 +namespace lemon {
    1.43 +
    1.44 +  ///\brief Base type for the Digraph Adaptors
    1.45 +  ///
    1.46 +  ///Base type for the Digraph Adaptors
    1.47 +  ///
    1.48 +  ///This is the base type for most of LEMON digraph adaptors. This
    1.49 +  ///class implements a trivial digraph adaptor i.e. it only wraps the
    1.50 +  ///functions and types of the digraph. The purpose of this class is
    1.51 +  ///to make easier implementing digraph adaptors. E.g. if an adaptor
    1.52 +  ///is considered which differs from the wrapped digraph only in some
    1.53 +  ///of its functions or types, then it can be derived from
    1.54 +  ///DigraphAdaptor, and only the differences should be implemented.
    1.55 +  template<typename _Digraph>
    1.56 +  class DigraphAdaptorBase {
    1.57 +  public:
    1.58 +    typedef _Digraph Digraph;
    1.59 +    typedef DigraphAdaptorBase Adaptor;
    1.60 +    typedef Digraph ParentDigraph;
    1.61 +
    1.62 +  protected:
    1.63 +    Digraph* _digraph;
    1.64 +    DigraphAdaptorBase() : _digraph(0) { }
    1.65 +    void setDigraph(Digraph& digraph) { _digraph = &digraph; }
    1.66 +
    1.67 +  public:
    1.68 +    DigraphAdaptorBase(Digraph& digraph) : _digraph(&digraph) { }
    1.69 +
    1.70 +    typedef typename Digraph::Node Node;
    1.71 +    typedef typename Digraph::Arc Arc;
    1.72 +   
    1.73 +    void first(Node& i) const { _digraph->first(i); }
    1.74 +    void first(Arc& i) const { _digraph->first(i); }
    1.75 +    void firstIn(Arc& i, const Node& n) const { _digraph->firstIn(i, n); }
    1.76 +    void firstOut(Arc& i, const Node& n ) const { _digraph->firstOut(i, n); }
    1.77 +
    1.78 +    void next(Node& i) const { _digraph->next(i); }
    1.79 +    void next(Arc& i) const { _digraph->next(i); }
    1.80 +    void nextIn(Arc& i) const { _digraph->nextIn(i); }
    1.81 +    void nextOut(Arc& i) const { _digraph->nextOut(i); }
    1.82 +
    1.83 +    Node source(const Arc& a) const { return _digraph->source(a); }
    1.84 +    Node target(const Arc& a) const { return _digraph->target(a); }
    1.85 +
    1.86 +    typedef NodeNumTagIndicator<Digraph> NodeNumTag;
    1.87 +    int nodeNum() const { return _digraph->nodeNum(); }
    1.88 +    
    1.89 +    typedef EdgeNumTagIndicator<Digraph> EdgeNumTag;
    1.90 +    int arcNum() const { return _digraph->arcNum(); }
    1.91 +
    1.92 +    typedef FindEdgeTagIndicator<Digraph> FindEdgeTag;
    1.93 +    Arc findArc(const Node& u, const Node& v, const Arc& prev = INVALID) {
    1.94 +      return _digraph->findArc(u, v, prev);
    1.95 +    }
    1.96 +  
    1.97 +    Node addNode() { return _digraph->addNode(); }
    1.98 +    Arc addArc(const Node& u, const Node& v) { return _digraph->addArc(u, v); }
    1.99 +
   1.100 +    void erase(const Node& n) const { _digraph->erase(n); }
   1.101 +    void erase(const Arc& a) const { _digraph->erase(a); }
   1.102 +  
   1.103 +    void clear() const { _digraph->clear(); }
   1.104 +    
   1.105 +    int id(const Node& n) const { return _digraph->id(n); }
   1.106 +    int id(const Arc& a) const { return _digraph->id(a); }
   1.107 +
   1.108 +    Node nodeFromId(int ix) const { return _digraph->nodeFromId(ix); }
   1.109 +    Arc arcFromId(int ix) const { return _digraph->arcFromId(ix); }
   1.110 +
   1.111 +    int maxNodeId() const { return _digraph->maxNodeId(); }
   1.112 +    int maxArcId() const { return _digraph->maxArcId(); }
   1.113 +
   1.114 +    typedef typename ItemSetTraits<Digraph, Node>::ItemNotifier NodeNotifier;
   1.115 +    NodeNotifier& notifier(Node) const { return _digraph->notifier(Node()); } 
   1.116 +
   1.117 +    typedef typename ItemSetTraits<Digraph, Arc>::ItemNotifier ArcNotifier;
   1.118 +    ArcNotifier& notifier(Arc) const { return _digraph->notifier(Arc()); } 
   1.119 +    
   1.120 +    template <typename _Value>
   1.121 +    class NodeMap : public Digraph::template NodeMap<_Value> {
   1.122 +    public:
   1.123 +
   1.124 +      typedef typename Digraph::template NodeMap<_Value> Parent;
   1.125 +
   1.126 +      explicit NodeMap(const Adaptor& adaptor) 
   1.127 +	: Parent(*adaptor._digraph) {}
   1.128 +
   1.129 +      NodeMap(const Adaptor& adaptor, const _Value& value)
   1.130 +	: Parent(*adaptor._digraph, value) { }
   1.131 +
   1.132 +    private:
   1.133 +      NodeMap& operator=(const NodeMap& cmap) {
   1.134 +        return operator=<NodeMap>(cmap);
   1.135 +      }
   1.136 +
   1.137 +      template <typename CMap>
   1.138 +      NodeMap& operator=(const CMap& cmap) {
   1.139 +        Parent::operator=(cmap);
   1.140 +        return *this;
   1.141 +      }
   1.142 +      
   1.143 +    };
   1.144 +
   1.145 +    template <typename _Value>
   1.146 +    class ArcMap : public Digraph::template ArcMap<_Value> {
   1.147 +    public:
   1.148 +      
   1.149 +      typedef typename Digraph::template ArcMap<_Value> Parent;
   1.150 +      
   1.151 +      explicit ArcMap(const Adaptor& adaptor) 
   1.152 +	: Parent(*adaptor._digraph) {}
   1.153 +
   1.154 +      ArcMap(const Adaptor& adaptor, const _Value& value)
   1.155 +	: Parent(*adaptor._digraph, value) {}
   1.156 +
   1.157 +    private:
   1.158 +      ArcMap& operator=(const ArcMap& cmap) {
   1.159 +        return operator=<ArcMap>(cmap);
   1.160 +      }
   1.161 +
   1.162 +      template <typename CMap>
   1.163 +      ArcMap& operator=(const CMap& cmap) {
   1.164 +        Parent::operator=(cmap);
   1.165 +        return *this;
   1.166 +      }
   1.167 +
   1.168 +    };
   1.169 +
   1.170 +  };
   1.171 +
   1.172 +  ///\ingroup graph_adaptors
   1.173 +  ///
   1.174 +  ///\brief Trivial Digraph Adaptor
   1.175 +  /// 
   1.176 +  /// This class is an adaptor which does not change the adapted
   1.177 +  /// digraph.  It can be used only to test the digraph adaptors.
   1.178 +  template <typename _Digraph>
   1.179 +  class DigraphAdaptor :
   1.180 +    public DigraphAdaptorExtender<DigraphAdaptorBase<_Digraph> > { 
   1.181 +  public:
   1.182 +    typedef _Digraph Digraph;
   1.183 +    typedef DigraphAdaptorExtender<DigraphAdaptorBase<_Digraph> > Parent;
   1.184 +  protected:
   1.185 +    DigraphAdaptor() : Parent() { }
   1.186 +
   1.187 +  public:
   1.188 +    explicit DigraphAdaptor(Digraph& digraph) { setDigraph(digraph); }
   1.189 +  };
   1.190 +
   1.191 +  /// \brief Just gives back a digraph adaptor
   1.192 +  ///
   1.193 +  /// Just gives back a digraph adaptor which 
   1.194 +  /// should be provide original digraph
   1.195 +  template<typename Digraph>
   1.196 +  DigraphAdaptor<const Digraph>
   1.197 +  digraphAdaptor(const Digraph& digraph) {
   1.198 +    return DigraphAdaptor<const Digraph>(digraph);
   1.199 +  }
   1.200 +
   1.201 +
   1.202 +  template <typename _Digraph>
   1.203 +  class RevDigraphAdaptorBase : public DigraphAdaptorBase<_Digraph> {
   1.204 +  public:
   1.205 +    typedef _Digraph Digraph;
   1.206 +    typedef DigraphAdaptorBase<_Digraph> Parent;
   1.207 +  protected:
   1.208 +    RevDigraphAdaptorBase() : Parent() { }
   1.209 +  public:
   1.210 +    typedef typename Parent::Node Node;
   1.211 +    typedef typename Parent::Arc Arc;
   1.212 +
   1.213 +    void firstIn(Arc& a, const Node& n) const { Parent::firstOut(a, n); }
   1.214 +    void firstOut(Arc& a, const Node& n ) const { Parent::firstIn(a, n); }
   1.215 +
   1.216 +    void nextIn(Arc& a) const { Parent::nextOut(a); }
   1.217 +    void nextOut(Arc& a) const { Parent::nextIn(a); }
   1.218 +
   1.219 +    Node source(const Arc& a) const { return Parent::target(a); }
   1.220 +    Node target(const Arc& a) const { return Parent::source(a); }
   1.221 +
   1.222 +    typedef FindEdgeTagIndicator<Digraph> FindEdgeTag;
   1.223 +    Arc findArc(const Node& u, const Node& v, 
   1.224 +		const Arc& prev = INVALID) {
   1.225 +      return Parent::findArc(v, u, prev);
   1.226 +    }
   1.227 +
   1.228 +  };
   1.229 +    
   1.230 +
   1.231 +  ///\ingroup graph_adaptors
   1.232 +  ///
   1.233 +  ///\brief A digraph adaptor which reverses the orientation of the arcs.
   1.234 +  ///
   1.235 +  /// If \c g is defined as
   1.236 +  ///\code
   1.237 +  /// ListDigraph g;
   1.238 +  ///\endcode
   1.239 +  /// then
   1.240 +  ///\code
   1.241 +  /// RevDigraphAdaptor<ListDigraph> ga(g);
   1.242 +  ///\endcode
   1.243 +  /// implements the digraph obtained from \c g by 
   1.244 +  /// reversing the orientation of its arcs.
   1.245 +  ///
   1.246 +  /// A good example of using RevDigraphAdaptor is to decide that the
   1.247 +  /// directed graph is wheter strongly connected or not. If from one
   1.248 +  /// node each node is reachable and from each node is reachable this
   1.249 +  /// node then and just then the digraph is strongly
   1.250 +  /// connected. Instead of this condition we use a little bit
   1.251 +  /// different. From one node each node ahould be reachable in the
   1.252 +  /// digraph and in the reversed digraph. Now this condition can be
   1.253 +  /// checked with the Dfs algorithm class and the RevDigraphAdaptor
   1.254 +  /// algorithm class.
   1.255 +  ///
   1.256 +  /// And look at the code:
   1.257 +  ///
   1.258 +  ///\code
   1.259 +  /// bool stronglyConnected(const Digraph& digraph) {
   1.260 +  ///   if (NodeIt(digraph) == INVALID) return true;
   1.261 +  ///   Dfs<Digraph> dfs(digraph);
   1.262 +  ///   dfs.run(NodeIt(digraph));
   1.263 +  ///   for (NodeIt it(digraph); it != INVALID; ++it) {
   1.264 +  ///     if (!dfs.reached(it)) {
   1.265 +  ///       return false;
   1.266 +  ///     }
   1.267 +  ///   }
   1.268 +  ///   typedef RevDigraphAdaptor<const Digraph> RDigraph;
   1.269 +  ///   RDigraph rdigraph(digraph);
   1.270 +  ///   DfsVisit<RDigraph> rdfs(rdigraph);
   1.271 +  ///   rdfs.run(NodeIt(digraph));
   1.272 +  ///   for (NodeIt it(digraph); it != INVALID; ++it) {
   1.273 +  ///     if (!rdfs.reached(it)) {
   1.274 +  ///       return false;
   1.275 +  ///     }
   1.276 +  ///   }
   1.277 +  ///   return true;
   1.278 +  /// }
   1.279 +  ///\endcode
   1.280 +  template<typename _Digraph>
   1.281 +  class RevDigraphAdaptor : 
   1.282 +    public DigraphAdaptorExtender<RevDigraphAdaptorBase<_Digraph> > {
   1.283 +  public:
   1.284 +    typedef _Digraph Digraph;
   1.285 +    typedef DigraphAdaptorExtender<
   1.286 +      RevDigraphAdaptorBase<_Digraph> > Parent;
   1.287 +  protected:
   1.288 +    RevDigraphAdaptor() { }
   1.289 +  public:
   1.290 +    explicit RevDigraphAdaptor(Digraph& digraph) { 
   1.291 +      Parent::setDigraph(digraph); 
   1.292 +    }
   1.293 +  };
   1.294 +
   1.295 +  /// \brief Just gives back a reverse digraph adaptor
   1.296 +  ///
   1.297 +  /// Just gives back a reverse digraph adaptor
   1.298 +  template<typename Digraph>
   1.299 +  RevDigraphAdaptor<const Digraph>
   1.300 +  revDigraphAdaptor(const Digraph& digraph) {
   1.301 +    return RevDigraphAdaptor<const Digraph>(digraph);
   1.302 +  }
   1.303 +
   1.304 +  template <typename _Digraph, typename _NodeFilterMap, 
   1.305 +	    typename _ArcFilterMap, bool checked = true>
   1.306 +  class SubDigraphAdaptorBase : public DigraphAdaptorBase<_Digraph> {
   1.307 +  public:
   1.308 +    typedef _Digraph Digraph;
   1.309 +    typedef _NodeFilterMap NodeFilterMap;
   1.310 +    typedef _ArcFilterMap ArcFilterMap;
   1.311 +
   1.312 +    typedef SubDigraphAdaptorBase Adaptor;
   1.313 +    typedef DigraphAdaptorBase<_Digraph> Parent;
   1.314 +  protected:
   1.315 +    NodeFilterMap* _node_filter;
   1.316 +    ArcFilterMap* _arc_filter;
   1.317 +    SubDigraphAdaptorBase() 
   1.318 +      : Parent(), _node_filter(0), _arc_filter(0) { }
   1.319 +
   1.320 +    void setNodeFilterMap(NodeFilterMap& node_filter) {
   1.321 +      _node_filter = &node_filter;
   1.322 +    }
   1.323 +    void setArcFilterMap(ArcFilterMap& arc_filter) {
   1.324 +      _arc_filter = &arc_filter;
   1.325 +    }
   1.326 +
   1.327 +  public:
   1.328 +
   1.329 +    typedef typename Parent::Node Node;
   1.330 +    typedef typename Parent::Arc Arc;
   1.331 +
   1.332 +    void first(Node& i) const { 
   1.333 +      Parent::first(i); 
   1.334 +      while (i != INVALID && !(*_node_filter)[i]) Parent::next(i); 
   1.335 +    }
   1.336 +
   1.337 +    void first(Arc& i) const { 
   1.338 +      Parent::first(i); 
   1.339 +      while (i != INVALID && (!(*_arc_filter)[i] 
   1.340 +	     || !(*_node_filter)[Parent::source(i)]
   1.341 +	     || !(*_node_filter)[Parent::target(i)])) Parent::next(i); 
   1.342 +    }
   1.343 +
   1.344 +    void firstIn(Arc& i, const Node& n) const { 
   1.345 +      Parent::firstIn(i, n); 
   1.346 +      while (i != INVALID && (!(*_arc_filter)[i] 
   1.347 +	     || !(*_node_filter)[Parent::source(i)])) Parent::nextIn(i); 
   1.348 +    }
   1.349 +
   1.350 +    void firstOut(Arc& i, const Node& n) const { 
   1.351 +      Parent::firstOut(i, n); 
   1.352 +      while (i != INVALID && (!(*_arc_filter)[i] 
   1.353 +	     || !(*_node_filter)[Parent::target(i)])) Parent::nextOut(i); 
   1.354 +    }
   1.355 +
   1.356 +    void next(Node& i) const { 
   1.357 +      Parent::next(i); 
   1.358 +      while (i != INVALID && !(*_node_filter)[i]) Parent::next(i); 
   1.359 +    }
   1.360 +
   1.361 +    void next(Arc& i) const { 
   1.362 +      Parent::next(i); 
   1.363 +      while (i != INVALID && (!(*_arc_filter)[i] 
   1.364 +	     || !(*_node_filter)[Parent::source(i)]
   1.365 +	     || !(*_node_filter)[Parent::target(i)])) Parent::next(i); 
   1.366 +    }
   1.367 +
   1.368 +    void nextIn(Arc& i) const { 
   1.369 +      Parent::nextIn(i); 
   1.370 +      while (i != INVALID && (!(*_arc_filter)[i] 
   1.371 +	     || !(*_node_filter)[Parent::source(i)])) Parent::nextIn(i); 
   1.372 +    }
   1.373 +
   1.374 +    void nextOut(Arc& i) const { 
   1.375 +      Parent::nextOut(i); 
   1.376 +      while (i != INVALID && (!(*_arc_filter)[i] 
   1.377 +	     || !(*_node_filter)[Parent::target(i)])) Parent::nextOut(i); 
   1.378 +    }
   1.379 +
   1.380 +    ///\e
   1.381 +
   1.382 +    /// This function hides \c n in the digraph, i.e. the iteration 
   1.383 +    /// jumps over it. This is done by simply setting the value of \c n  
   1.384 +    /// to be false in the corresponding node-map.
   1.385 +    void hide(const Node& n) const { _node_filter->set(n, false); }
   1.386 +
   1.387 +    ///\e
   1.388 +
   1.389 +    /// This function hides \c a in the digraph, i.e. the iteration 
   1.390 +    /// jumps over it. This is done by simply setting the value of \c a
   1.391 +    /// to be false in the corresponding arc-map.
   1.392 +    void hide(const Arc& a) const { _arc_filter->set(a, false); }
   1.393 +
   1.394 +    ///\e
   1.395 +
   1.396 +    /// The value of \c n is set to be true in the node-map which stores 
   1.397 +    /// hide information. If \c n was hidden previuosly, then it is shown 
   1.398 +    /// again
   1.399 +     void unHide(const Node& n) const { _node_filter->set(n, true); }
   1.400 +
   1.401 +    ///\e
   1.402 +
   1.403 +    /// The value of \c a is set to be true in the arc-map which stores 
   1.404 +    /// hide information. If \c a was hidden previuosly, then it is shown 
   1.405 +    /// again
   1.406 +    void unHide(const Arc& a) const { _arc_filter->set(a, true); }
   1.407 +
   1.408 +    /// Returns true if \c n is hidden.
   1.409 +    
   1.410 +    ///\e
   1.411 +    ///
   1.412 +    bool hidden(const Node& n) const { return !(*_node_filter)[n]; }
   1.413 +
   1.414 +    /// Returns true if \c a is hidden.
   1.415 +    
   1.416 +    ///\e
   1.417 +    ///
   1.418 +    bool hidden(const Arc& a) const { return !(*_arc_filter)[a]; }
   1.419 +
   1.420 +    typedef False NodeNumTag;
   1.421 +    typedef False EdgeNumTag;
   1.422 +
   1.423 +    typedef FindEdgeTagIndicator<Digraph> FindEdgeTag;
   1.424 +    Arc findArc(const Node& source, const Node& target, 
   1.425 +		const Arc& prev = INVALID) {
   1.426 +      if (!(*_node_filter)[source] || !(*_node_filter)[target]) {
   1.427 +        return INVALID;
   1.428 +      }
   1.429 +      Arc arc = Parent::findArc(source, target, prev);
   1.430 +      while (arc != INVALID && !(*_arc_filter)[arc]) {
   1.431 +        arc = Parent::findArc(source, target, arc);
   1.432 +      }
   1.433 +      return arc;
   1.434 +    }
   1.435 +
   1.436 +    template <typename _Value>
   1.437 +    class NodeMap : public SubMapExtender<Adaptor, 
   1.438 +        typename Parent::template NodeMap<_Value> > {
   1.439 +    public:
   1.440 +      typedef _Value Value;
   1.441 +      typedef SubMapExtender<Adaptor, typename Parent::
   1.442 +                             template NodeMap<Value> > MapParent;
   1.443 +    
   1.444 +      NodeMap(const Adaptor& adaptor) 
   1.445 +	: MapParent(adaptor) {}
   1.446 +      NodeMap(const Adaptor& adaptor, const Value& value) 
   1.447 +	: MapParent(adaptor, value) {}
   1.448 +    
   1.449 +    private:
   1.450 +      NodeMap& operator=(const NodeMap& cmap) {
   1.451 +	return operator=<NodeMap>(cmap);
   1.452 +      }
   1.453 +    
   1.454 +      template <typename CMap>
   1.455 +      NodeMap& operator=(const CMap& cmap) {
   1.456 +        MapParent::operator=(cmap);
   1.457 +	return *this;
   1.458 +      }
   1.459 +    };
   1.460 +
   1.461 +    template <typename _Value>
   1.462 +    class ArcMap : public SubMapExtender<Adaptor, 
   1.463 +	typename Parent::template ArcMap<_Value> > {
   1.464 +    public:
   1.465 +      typedef _Value Value;
   1.466 +      typedef SubMapExtender<Adaptor, typename Parent::
   1.467 +                             template ArcMap<Value> > MapParent;
   1.468 +    
   1.469 +      ArcMap(const Adaptor& adaptor) 
   1.470 +	: MapParent(adaptor) {}
   1.471 +      ArcMap(const Adaptor& adaptor, const Value& value) 
   1.472 +	: MapParent(adaptor, value) {}
   1.473 +    
   1.474 +    private:
   1.475 +      ArcMap& operator=(const ArcMap& cmap) {
   1.476 +	return operator=<ArcMap>(cmap);
   1.477 +      }
   1.478 +    
   1.479 +      template <typename CMap>
   1.480 +      ArcMap& operator=(const CMap& cmap) {
   1.481 +        MapParent::operator=(cmap);
   1.482 +	return *this;
   1.483 +      }
   1.484 +    };
   1.485 +
   1.486 +  };
   1.487 +
   1.488 +  template <typename _Digraph, typename _NodeFilterMap, typename _ArcFilterMap>
   1.489 +  class SubDigraphAdaptorBase<_Digraph, _NodeFilterMap, _ArcFilterMap, false> 
   1.490 +    : public DigraphAdaptorBase<_Digraph> {
   1.491 +  public:
   1.492 +    typedef _Digraph Digraph;
   1.493 +    typedef _NodeFilterMap NodeFilterMap;
   1.494 +    typedef _ArcFilterMap ArcFilterMap;
   1.495 +
   1.496 +    typedef SubDigraphAdaptorBase Adaptor;
   1.497 +    typedef DigraphAdaptorBase<Digraph> Parent;
   1.498 +  protected:
   1.499 +    NodeFilterMap* _node_filter;
   1.500 +    ArcFilterMap* _arc_filter;
   1.501 +    SubDigraphAdaptorBase() 
   1.502 +      : Parent(), _node_filter(0), _arc_filter(0) { }
   1.503 +
   1.504 +    void setNodeFilterMap(NodeFilterMap& node_filter) {
   1.505 +      _node_filter = &node_filter;
   1.506 +    }
   1.507 +    void setArcFilterMap(ArcFilterMap& arc_filter) {
   1.508 +      _arc_filter = &arc_filter;
   1.509 +    }
   1.510 +
   1.511 +  public:
   1.512 +
   1.513 +    typedef typename Parent::Node Node;
   1.514 +    typedef typename Parent::Arc Arc;
   1.515 +
   1.516 +    void first(Node& i) const { 
   1.517 +      Parent::first(i); 
   1.518 +      while (i!=INVALID && !(*_node_filter)[i]) Parent::next(i); 
   1.519 +    }
   1.520 +
   1.521 +    void first(Arc& i) const { 
   1.522 +      Parent::first(i); 
   1.523 +      while (i!=INVALID && !(*_arc_filter)[i]) Parent::next(i); 
   1.524 +    }
   1.525 +
   1.526 +    void firstIn(Arc& i, const Node& n) const { 
   1.527 +      Parent::firstIn(i, n); 
   1.528 +      while (i!=INVALID && !(*_arc_filter)[i]) Parent::nextIn(i); 
   1.529 +    }
   1.530 +
   1.531 +    void firstOut(Arc& i, const Node& n) const { 
   1.532 +      Parent::firstOut(i, n); 
   1.533 +      while (i!=INVALID && !(*_arc_filter)[i]) Parent::nextOut(i); 
   1.534 +    }
   1.535 +
   1.536 +    void next(Node& i) const { 
   1.537 +      Parent::next(i); 
   1.538 +      while (i!=INVALID && !(*_node_filter)[i]) Parent::next(i); 
   1.539 +    }
   1.540 +    void next(Arc& i) const { 
   1.541 +      Parent::next(i); 
   1.542 +      while (i!=INVALID && !(*_arc_filter)[i]) Parent::next(i); 
   1.543 +    }
   1.544 +    void nextIn(Arc& i) const { 
   1.545 +      Parent::nextIn(i); 
   1.546 +      while (i!=INVALID && !(*_arc_filter)[i]) Parent::nextIn(i); 
   1.547 +    }
   1.548 +
   1.549 +    void nextOut(Arc& i) const { 
   1.550 +      Parent::nextOut(i); 
   1.551 +      while (i!=INVALID && !(*_arc_filter)[i]) Parent::nextOut(i); 
   1.552 +    }
   1.553 +
   1.554 +    ///\e
   1.555 +
   1.556 +    /// This function hides \c n in the digraph, i.e. the iteration 
   1.557 +    /// jumps over it. This is done by simply setting the value of \c n  
   1.558 +    /// to be false in the corresponding node-map.
   1.559 +    void hide(const Node& n) const { _node_filter->set(n, false); }
   1.560 +
   1.561 +    ///\e
   1.562 +
   1.563 +    /// This function hides \c e in the digraph, i.e. the iteration 
   1.564 +    /// jumps over it. This is done by simply setting the value of \c e  
   1.565 +    /// to be false in the corresponding arc-map.
   1.566 +    void hide(const Arc& e) const { _arc_filter->set(e, false); }
   1.567 +
   1.568 +    ///\e
   1.569 +
   1.570 +    /// The value of \c n is set to be true in the node-map which stores 
   1.571 +    /// hide information. If \c n was hidden previuosly, then it is shown 
   1.572 +    /// again
   1.573 +     void unHide(const Node& n) const { _node_filter->set(n, true); }
   1.574 +
   1.575 +    ///\e
   1.576 +
   1.577 +    /// The value of \c e is set to be true in the arc-map which stores 
   1.578 +    /// hide information. If \c e was hidden previuosly, then it is shown 
   1.579 +    /// again
   1.580 +    void unHide(const Arc& e) const { _arc_filter->set(e, true); }
   1.581 +
   1.582 +    /// Returns true if \c n is hidden.
   1.583 +    
   1.584 +    ///\e
   1.585 +    ///
   1.586 +    bool hidden(const Node& n) const { return !(*_node_filter)[n]; }
   1.587 +
   1.588 +    /// Returns true if \c n is hidden.
   1.589 +    
   1.590 +    ///\e
   1.591 +    ///
   1.592 +    bool hidden(const Arc& e) const { return !(*_arc_filter)[e]; }
   1.593 +
   1.594 +    typedef False NodeNumTag;
   1.595 +    typedef False EdgeNumTag;
   1.596 +
   1.597 +    typedef FindEdgeTagIndicator<Digraph> FindEdgeTag;
   1.598 +    Arc findArc(const Node& source, const Node& target, 
   1.599 +		  const Arc& prev = INVALID) {
   1.600 +      if (!(*_node_filter)[source] || !(*_node_filter)[target]) {
   1.601 +        return INVALID;
   1.602 +      }
   1.603 +      Arc arc = Parent::findArc(source, target, prev);
   1.604 +      while (arc != INVALID && !(*_arc_filter)[arc]) {
   1.605 +        arc = Parent::findArc(source, target, arc);
   1.606 +      }
   1.607 +      return arc;
   1.608 +    }
   1.609 +
   1.610 +    template <typename _Value>
   1.611 +    class NodeMap : public SubMapExtender<Adaptor, 
   1.612 +        typename Parent::template NodeMap<_Value> > {
   1.613 +    public:
   1.614 +      typedef _Value Value;
   1.615 +      typedef SubMapExtender<Adaptor, typename Parent::
   1.616 +                             template NodeMap<Value> > MapParent;
   1.617 +    
   1.618 +      NodeMap(const Adaptor& adaptor) 
   1.619 +	: MapParent(adaptor) {}
   1.620 +      NodeMap(const Adaptor& adaptor, const Value& value) 
   1.621 +	: MapParent(adaptor, value) {}
   1.622 +    
   1.623 +    private:
   1.624 +      NodeMap& operator=(const NodeMap& cmap) {
   1.625 +	return operator=<NodeMap>(cmap);
   1.626 +      }
   1.627 +    
   1.628 +      template <typename CMap>
   1.629 +      NodeMap& operator=(const CMap& cmap) {
   1.630 +        MapParent::operator=(cmap);
   1.631 +	return *this;
   1.632 +      }
   1.633 +    };
   1.634 +
   1.635 +    template <typename _Value>
   1.636 +    class ArcMap : public SubMapExtender<Adaptor, 
   1.637 +	typename Parent::template ArcMap<_Value> > {
   1.638 +    public:
   1.639 +      typedef _Value Value;
   1.640 +      typedef SubMapExtender<Adaptor, typename Parent::
   1.641 +                             template ArcMap<Value> > MapParent;
   1.642 +    
   1.643 +      ArcMap(const Adaptor& adaptor) 
   1.644 +	: MapParent(adaptor) {}
   1.645 +      ArcMap(const Adaptor& adaptor, const Value& value) 
   1.646 +	: MapParent(adaptor, value) {}
   1.647 +    
   1.648 +    private:
   1.649 +      ArcMap& operator=(const ArcMap& cmap) {
   1.650 +	return operator=<ArcMap>(cmap);
   1.651 +      }
   1.652 +    
   1.653 +      template <typename CMap>
   1.654 +      ArcMap& operator=(const CMap& cmap) {
   1.655 +        MapParent::operator=(cmap);
   1.656 +	return *this;
   1.657 +      }
   1.658 +    };
   1.659 +
   1.660 +  };
   1.661 +
   1.662 +  /// \ingroup graph_adaptors
   1.663 +  ///
   1.664 +  /// \brief A digraph adaptor for hiding nodes and arcs from a digraph.
   1.665 +  /// 
   1.666 +  /// SubDigraphAdaptor shows the digraph with filtered node-set and 
   1.667 +  /// arc-set. If the \c checked parameter is true then it filters the arcset
   1.668 +  /// to do not get invalid arcs without source or target.
   1.669 +  /// Let \f$ G=(V, A) \f$ be a directed digraph
   1.670 +  /// and suppose that the digraph instance \c g of type ListDigraph
   1.671 +  /// implements \f$ G \f$.
   1.672 +  /// Let moreover \f$ b_V \f$ and \f$ b_A \f$ be bool-valued functions resp.
   1.673 +  /// on the node-set and arc-set.
   1.674 +  /// SubDigraphAdaptor<...>::NodeIt iterates 
   1.675 +  /// on the node-set \f$ \{v\in V : b_V(v)=true\} \f$ and 
   1.676 +  /// SubDigraphAdaptor<...>::ArcIt iterates 
   1.677 +  /// on the arc-set \f$ \{e\in A : b_A(e)=true\} \f$. Similarly, 
   1.678 +  /// SubDigraphAdaptor<...>::OutArcIt and
   1.679 +  /// SubDigraphAdaptor<...>::InArcIt iterates 
   1.680 +  /// only on arcs leaving and entering a specific node which have true value.
   1.681 +  /// 
   1.682 +  /// If the \c checked template parameter is false then we have to
   1.683 +  /// note that the node-iterator cares only the filter on the
   1.684 +  /// node-set, and the arc-iterator cares only the filter on the
   1.685 +  /// arc-set.  This way the arc-map should filter all arcs which's
   1.686 +  /// source or target is filtered by the node-filter.
   1.687 +  ///\code
   1.688 +  /// typedef ListDigraph Digraph;
   1.689 +  /// DIGRAPH_TYPEDEFS(Digraph);
   1.690 +  /// Digraph g;
   1.691 +  /// Node u=g.addNode(); //node of id 0
   1.692 +  /// Node v=g.addNode(); //node of id 1
   1.693 +  /// Arc a=g.addArc(u, v); //arc of id 0
   1.694 +  /// Arc f=g.addArc(v, u); //arc of id 1
   1.695 +  /// BoolNodeMap nm(g, true);
   1.696 +  /// nm.set(u, false);
   1.697 +  /// BoolArcMap am(g, true);
   1.698 +  /// am.set(a, false);
   1.699 +  /// typedef SubDigraphAdaptor<Digraph, BoolNodeMap, BoolArcMap> SubGA;
   1.700 +  /// SubGA ga(g, nm, am);
   1.701 +  /// for (SubGA::NodeIt n(ga); n!=INVALID; ++n)
   1.702 +  ///   std::cout << g.id(n) << std::endl;
   1.703 +  /// std::cout << ":-)" << std::endl;
   1.704 +  /// for (SubGA::ArcIt a(ga); a!=INVALID; ++a) 
   1.705 +  ///   std::cout << g.id(a) << std::endl;
   1.706 +  ///\endcode
   1.707 +  /// The output of the above code is the following.
   1.708 +  ///\code
   1.709 +  /// 1
   1.710 +  /// :-)
   1.711 +  /// 1
   1.712 +  ///\endcode
   1.713 +  /// Note that \c n is of type \c SubGA::NodeIt, but it can be converted to
   1.714 +  /// \c Digraph::Node that is why \c g.id(n) can be applied.
   1.715 +  /// 
   1.716 +  /// For other examples see also the documentation of
   1.717 +  /// NodeSubDigraphAdaptor and ArcSubDigraphAdaptor.
   1.718 +  template<typename _Digraph, 
   1.719 +	   typename _NodeFilterMap = typename _Digraph::template NodeMap<bool>, 
   1.720 +	   typename _ArcFilterMap = typename _Digraph::template ArcMap<bool>, 
   1.721 +	   bool checked = true>
   1.722 +  class SubDigraphAdaptor : 
   1.723 +    public DigraphAdaptorExtender<
   1.724 +    SubDigraphAdaptorBase<_Digraph, _NodeFilterMap, _ArcFilterMap, checked> > {
   1.725 +  public:
   1.726 +    typedef _Digraph Digraph;
   1.727 +    typedef _NodeFilterMap NodeFilterMap;
   1.728 +    typedef _ArcFilterMap ArcFilterMap;
   1.729 +
   1.730 +    typedef DigraphAdaptorExtender<
   1.731 +      SubDigraphAdaptorBase<Digraph, NodeFilterMap, ArcFilterMap, checked> >
   1.732 +    Parent;
   1.733 +
   1.734 +  protected:
   1.735 +    SubDigraphAdaptor() { }
   1.736 +  public:
   1.737 +
   1.738 +    SubDigraphAdaptor(Digraph& digraph, NodeFilterMap& node_filter, 
   1.739 +		      ArcFilterMap& arc_filter) { 
   1.740 +      setDigraph(digraph);
   1.741 +      setNodeFilterMap(node_filter);
   1.742 +      setArcFilterMap(arc_filter);
   1.743 +    }
   1.744 +
   1.745 +  };
   1.746 +
   1.747 +  /// \brief Just gives back a sub digraph adaptor
   1.748 +  ///
   1.749 +  /// Just gives back a sub digraph adaptor
   1.750 +  template<typename Digraph, typename NodeFilterMap, typename ArcFilterMap>
   1.751 +  SubDigraphAdaptor<const Digraph, NodeFilterMap, ArcFilterMap>
   1.752 +  subDigraphAdaptor(const Digraph& digraph, 
   1.753 +		    NodeFilterMap& nfm, ArcFilterMap& afm) {
   1.754 +    return SubDigraphAdaptor<const Digraph, NodeFilterMap, ArcFilterMap>
   1.755 +      (digraph, nfm, afm);
   1.756 +  }
   1.757 +
   1.758 +  template<typename Digraph, typename NodeFilterMap, typename ArcFilterMap>
   1.759 +  SubDigraphAdaptor<const Digraph, const NodeFilterMap, ArcFilterMap>
   1.760 +  subDigraphAdaptor(const Digraph& digraph, 
   1.761 +                   NodeFilterMap& nfm, ArcFilterMap& afm) {
   1.762 +    return SubDigraphAdaptor<const Digraph, const NodeFilterMap, ArcFilterMap>
   1.763 +      (digraph, nfm, afm);
   1.764 +  }
   1.765 +
   1.766 +  template<typename Digraph, typename NodeFilterMap, typename ArcFilterMap>
   1.767 +  SubDigraphAdaptor<const Digraph, NodeFilterMap, const ArcFilterMap>
   1.768 +  subDigraphAdaptor(const Digraph& digraph, 
   1.769 +                   NodeFilterMap& nfm, ArcFilterMap& afm) {
   1.770 +    return SubDigraphAdaptor<const Digraph, NodeFilterMap, const ArcFilterMap>
   1.771 +      (digraph, nfm, afm);
   1.772 +  }
   1.773 +
   1.774 +  template<typename Digraph, typename NodeFilterMap, typename ArcFilterMap>
   1.775 +  SubDigraphAdaptor<const Digraph, const NodeFilterMap, const ArcFilterMap>
   1.776 +  subDigraphAdaptor(const Digraph& digraph, 
   1.777 +                   NodeFilterMap& nfm, ArcFilterMap& afm) {
   1.778 +    return SubDigraphAdaptor<const Digraph, const NodeFilterMap, 
   1.779 +      const ArcFilterMap>(digraph, nfm, afm);
   1.780 +  }
   1.781 +
   1.782 +
   1.783 +
   1.784 +  ///\ingroup graph_adaptors
   1.785 +  ///
   1.786 +  ///\brief An adaptor for hiding nodes from a digraph.
   1.787 +  ///
   1.788 +  ///An adaptor for hiding nodes from a digraph.  This adaptor
   1.789 +  ///specializes SubDigraphAdaptor in the way that only the node-set
   1.790 +  ///can be filtered. In usual case the checked parameter is true, we
   1.791 +  ///get the induced subgraph. But if the checked parameter is false
   1.792 +  ///then we can filter only isolated nodes.
   1.793 +  template<typename _Digraph, 
   1.794 +	   typename _NodeFilterMap = typename _Digraph::template NodeMap<bool>, 
   1.795 +	   bool checked = true>
   1.796 +  class NodeSubDigraphAdaptor : 
   1.797 +    public SubDigraphAdaptor<_Digraph, _NodeFilterMap, 
   1.798 +			     ConstMap<typename _Digraph::Arc, bool>, checked> {
   1.799 +  public:
   1.800 +
   1.801 +    typedef _Digraph Digraph;
   1.802 +    typedef _NodeFilterMap NodeFilterMap;
   1.803 +
   1.804 +    typedef SubDigraphAdaptor<Digraph, NodeFilterMap, 
   1.805 +			      ConstMap<typename Digraph::Arc, bool>, checked> 
   1.806 +    Parent;
   1.807 +
   1.808 +  protected:
   1.809 +    ConstMap<typename Digraph::Arc, bool> const_true_map;
   1.810 +
   1.811 +    NodeSubDigraphAdaptor() : const_true_map(true) {
   1.812 +      Parent::setArcFilterMap(const_true_map);
   1.813 +    }
   1.814 +
   1.815 +  public:
   1.816 +
   1.817 +    NodeSubDigraphAdaptor(Digraph& _digraph, NodeFilterMap& node_filter) : 
   1.818 +      Parent(), const_true_map(true) { 
   1.819 +      Parent::setDigraph(_digraph);
   1.820 +      Parent::setNodeFilterMap(node_filter);
   1.821 +      Parent::setArcFilterMap(const_true_map);
   1.822 +    }
   1.823 +
   1.824 +  };
   1.825 +
   1.826 +
   1.827 +  /// \brief Just gives back a \c NodeSubDigraphAdaptor
   1.828 +  ///
   1.829 +  /// Just gives back a \c NodeSubDigraphAdaptor
   1.830 +  template<typename Digraph, typename NodeFilterMap>
   1.831 +  NodeSubDigraphAdaptor<const Digraph, NodeFilterMap>
   1.832 +  nodeSubDigraphAdaptor(const Digraph& digraph, NodeFilterMap& nfm) {
   1.833 +    return NodeSubDigraphAdaptor<const Digraph, NodeFilterMap>(digraph, nfm);
   1.834 +  }
   1.835 +
   1.836 +  template<typename Digraph, typename NodeFilterMap>
   1.837 +  NodeSubDigraphAdaptor<const Digraph, const NodeFilterMap>
   1.838 +  nodeSubDigraphAdaptor(const Digraph& digraph, const NodeFilterMap& nfm) {
   1.839 +    return NodeSubDigraphAdaptor<const Digraph, const NodeFilterMap>
   1.840 +      (digraph, nfm);
   1.841 +  }
   1.842 +
   1.843 +  ///\ingroup graph_adaptors
   1.844 +  ///
   1.845 +  ///\brief An adaptor for hiding arcs from a digraph.
   1.846 +  ///
   1.847 +  ///An adaptor for hiding arcs from a digraph. This adaptor
   1.848 +  ///specializes SubDigraphAdaptor in the way that only the arc-set
   1.849 +  ///can be filtered. The usefulness of this adaptor is demonstrated
   1.850 +  ///in the problem of searching a maximum number of arc-disjoint
   1.851 +  ///shortest paths between two nodes \c s and \c t. Shortest here
   1.852 +  ///means being shortest w.r.t.  non-negative arc-lengths. Note that
   1.853 +  ///the comprehension of the presented solution need's some
   1.854 +  ///elementary knowlarc from combinatorial optimization.
   1.855 +  ///
   1.856 +  ///If a single shortest path is to be searched between \c s and \c
   1.857 +  ///t, then this can be done easily by applying the Dijkstra
   1.858 +  ///algorithm. What happens, if a maximum number of arc-disjoint
   1.859 +  ///shortest paths is to be computed. It can be proved that an arc
   1.860 +  ///can be in a shortest path if and only if it is tight with respect
   1.861 +  ///to the potential function computed by Dijkstra.  Moreover, any
   1.862 +  ///path containing only such arcs is a shortest one.  Thus we have
   1.863 +  ///to compute a maximum number of arc-disjoint paths between \c s
   1.864 +  ///and \c t in the digraph which has arc-set all the tight arcs. The
   1.865 +  ///computation will be demonstrated on the following digraph, which
   1.866 +  ///is read from the dimacs file \c sub_digraph_adaptor_demo.dim.
   1.867 +  ///The full source code is available in \ref
   1.868 +  ///sub_digraph_adaptor_demo.cc.  If you are interested in more demo
   1.869 +  ///programs, you can use \ref dim_to_dot.cc to generate .dot files
   1.870 +  ///from dimacs files.  The .dot file of the following figure was
   1.871 +  ///generated by the demo program \ref dim_to_dot.cc.
   1.872 +  ///
   1.873 +  ///\dot
   1.874 +  ///didigraph lemon_dot_example {
   1.875 +  ///node [ shape=ellipse, fontname=Helvetica, fontsize=10 ];
   1.876 +  ///n0 [ label="0 (s)" ];
   1.877 +  ///n1 [ label="1" ];
   1.878 +  ///n2 [ label="2" ];
   1.879 +  ///n3 [ label="3" ];
   1.880 +  ///n4 [ label="4" ];
   1.881 +  ///n5 [ label="5" ];
   1.882 +  ///n6 [ label="6 (t)" ];
   1.883 +  ///arc [ shape=ellipse, fontname=Helvetica, fontsize=10 ];
   1.884 +  ///n5 ->  n6 [ label="9, length:4" ];
   1.885 +  ///n4 ->  n6 [ label="8, length:2" ];
   1.886 +  ///n3 ->  n5 [ label="7, length:1" ];
   1.887 +  ///n2 ->  n5 [ label="6, length:3" ];
   1.888 +  ///n2 ->  n6 [ label="5, length:5" ];
   1.889 +  ///n2 ->  n4 [ label="4, length:2" ];
   1.890 +  ///n1 ->  n4 [ label="3, length:3" ];
   1.891 +  ///n0 ->  n3 [ label="2, length:1" ];
   1.892 +  ///n0 ->  n2 [ label="1, length:2" ];
   1.893 +  ///n0 ->  n1 [ label="0, length:3" ];
   1.894 +  ///}
   1.895 +  ///\enddot
   1.896 +  ///
   1.897 +  ///\code
   1.898 +  ///Digraph g;
   1.899 +  ///Node s, t;
   1.900 +  ///LengthMap length(g);
   1.901 +  ///
   1.902 +  ///readDimacs(std::cin, g, length, s, t);
   1.903 +  ///
   1.904 +  ///cout << "arcs with lengths (of form id, source--length->target): " << endl;
   1.905 +  ///for(ArcIt e(g); e!=INVALID; ++e) 
   1.906 +  ///  cout << g.id(e) << ", " << g.id(g.source(e)) << "--" 
   1.907 +  ///       << length[e] << "->" << g.id(g.target(e)) << endl;
   1.908 +  ///
   1.909 +  ///cout << "s: " << g.id(s) << " t: " << g.id(t) << endl;
   1.910 +  ///\endcode
   1.911 +  ///Next, the potential function is computed with Dijkstra.
   1.912 +  ///\code
   1.913 +  ///typedef Dijkstra<Digraph, LengthMap> Dijkstra;
   1.914 +  ///Dijkstra dijkstra(g, length);
   1.915 +  ///dijkstra.run(s);
   1.916 +  ///\endcode
   1.917 +  ///Next, we consrtruct a map which filters the arc-set to the tight arcs.
   1.918 +  ///\code
   1.919 +  ///typedef TightArcFilterMap<Digraph, const Dijkstra::DistMap, LengthMap> 
   1.920 +  ///  TightArcFilter;
   1.921 +  ///TightArcFilter tight_arc_filter(g, dijkstra.distMap(), length);
   1.922 +  ///
   1.923 +  ///typedef ArcSubDigraphAdaptor<Digraph, TightArcFilter> SubGA;
   1.924 +  ///SubGA ga(g, tight_arc_filter);
   1.925 +  ///\endcode
   1.926 +  ///Then, the maximum nimber of arc-disjoint \c s-\c t paths are computed 
   1.927 +  ///with a max flow algorithm Preflow.
   1.928 +  ///\code
   1.929 +  ///ConstMap<Arc, int> const_1_map(1);
   1.930 +  ///Digraph::ArcMap<int> flow(g, 0);
   1.931 +  ///
   1.932 +  ///Preflow<SubGA, ConstMap<Arc, int>, Digraph::ArcMap<int> > 
   1.933 +  ///  preflow(ga, const_1_map, s, t);
   1.934 +  ///preflow.run();
   1.935 +  ///\endcode
   1.936 +  ///Last, the output is:
   1.937 +  ///\code  
   1.938 +  ///cout << "maximum number of arc-disjoint shortest path: " 
   1.939 +  ///     << preflow.flowValue() << endl;
   1.940 +  ///cout << "arcs of the maximum number of arc-disjoint shortest s-t paths: " 
   1.941 +  ///     << endl;
   1.942 +  ///for(ArcIt e(g); e!=INVALID; ++e) 
   1.943 +  ///  if (preflow.flow(e))
   1.944 +  ///    cout << " " << g.id(g.source(e)) << "--"
   1.945 +  ///         << length[e] << "->" << g.id(g.target(e)) << endl;
   1.946 +  ///\endcode
   1.947 +  ///The program has the following (expected :-)) output:
   1.948 +  ///\code
   1.949 +  ///arcs with lengths (of form id, source--length->target):
   1.950 +  /// 9, 5--4->6
   1.951 +  /// 8, 4--2->6
   1.952 +  /// 7, 3--1->5
   1.953 +  /// 6, 2--3->5
   1.954 +  /// 5, 2--5->6
   1.955 +  /// 4, 2--2->4
   1.956 +  /// 3, 1--3->4
   1.957 +  /// 2, 0--1->3
   1.958 +  /// 1, 0--2->2
   1.959 +  /// 0, 0--3->1
   1.960 +  ///s: 0 t: 6
   1.961 +  ///maximum number of arc-disjoint shortest path: 2
   1.962 +  ///arcs of the maximum number of arc-disjoint shortest s-t paths:
   1.963 +  /// 9, 5--4->6
   1.964 +  /// 8, 4--2->6
   1.965 +  /// 7, 3--1->5
   1.966 +  /// 4, 2--2->4
   1.967 +  /// 2, 0--1->3
   1.968 +  /// 1, 0--2->2
   1.969 +  ///\endcode
   1.970 +  template<typename _Digraph, typename _ArcFilterMap>
   1.971 +  class ArcSubDigraphAdaptor : 
   1.972 +    public SubDigraphAdaptor<_Digraph, ConstMap<typename _Digraph::Node, bool>, 
   1.973 +			     _ArcFilterMap, false> {
   1.974 +  public:
   1.975 +    typedef _Digraph Digraph;
   1.976 +    typedef _ArcFilterMap ArcFilterMap;
   1.977 +
   1.978 +    typedef SubDigraphAdaptor<Digraph, ConstMap<typename Digraph::Node, bool>, 
   1.979 +			      ArcFilterMap, false> Parent;
   1.980 +  protected:
   1.981 +    ConstMap<typename Digraph::Node, bool> const_true_map;
   1.982 +
   1.983 +    ArcSubDigraphAdaptor() : const_true_map(true) {
   1.984 +      Parent::setNodeFilterMap(const_true_map);
   1.985 +    }
   1.986 +
   1.987 +  public:
   1.988 +
   1.989 +    ArcSubDigraphAdaptor(Digraph& digraph, ArcFilterMap& arc_filter) 
   1.990 +      : Parent(), const_true_map(true) { 
   1.991 +      Parent::setDigraph(digraph);
   1.992 +      Parent::setNodeFilterMap(const_true_map);
   1.993 +      Parent::setArcFilterMap(arc_filter);
   1.994 +    }
   1.995 +
   1.996 +  };
   1.997 +
   1.998 +  /// \brief Just gives back an arc sub digraph adaptor
   1.999 +  ///
  1.1000 +  /// Just gives back an arc sub digraph adaptor
  1.1001 +  template<typename Digraph, typename ArcFilterMap>
  1.1002 +  ArcSubDigraphAdaptor<const Digraph, ArcFilterMap>
  1.1003 +  arcSubDigraphAdaptor(const Digraph& digraph, ArcFilterMap& afm) {
  1.1004 +    return ArcSubDigraphAdaptor<const Digraph, ArcFilterMap>(digraph, afm);
  1.1005 +  }
  1.1006 +
  1.1007 +  template<typename Digraph, typename ArcFilterMap>
  1.1008 +  ArcSubDigraphAdaptor<const Digraph, const ArcFilterMap>
  1.1009 +  arcSubDigraphAdaptor(const Digraph& digraph, const ArcFilterMap& afm) {
  1.1010 +    return ArcSubDigraphAdaptor<const Digraph, const ArcFilterMap>
  1.1011 +      (digraph, afm);
  1.1012 +  }
  1.1013 +
  1.1014 +  template <typename _Digraph>
  1.1015 +  class UndirDigraphAdaptorBase { 
  1.1016 +  public:
  1.1017 +    typedef _Digraph Digraph;
  1.1018 +    typedef UndirDigraphAdaptorBase Adaptor;
  1.1019 +
  1.1020 +    typedef True UndirectedTag;
  1.1021 +
  1.1022 +    typedef typename Digraph::Arc Edge;
  1.1023 +    typedef typename Digraph::Node Node;
  1.1024 +
  1.1025 +    class Arc : public Edge {
  1.1026 +      friend class UndirDigraphAdaptorBase;
  1.1027 +    protected:
  1.1028 +      bool _forward;
  1.1029 +
  1.1030 +      Arc(const Edge& edge, bool forward) :
  1.1031 +        Edge(edge), _forward(forward) {}
  1.1032 +
  1.1033 +    public:
  1.1034 +      Arc() {}
  1.1035 +
  1.1036 +      Arc(Invalid) : Edge(INVALID), _forward(true) {}
  1.1037 +
  1.1038 +      bool operator==(const Arc &other) const {
  1.1039 +	return _forward == other._forward && 
  1.1040 +	  static_cast<const Edge&>(*this) == static_cast<const Edge&>(other);
  1.1041 +      }
  1.1042 +      bool operator!=(const Arc &other) const {
  1.1043 +	return _forward != other._forward || 
  1.1044 +	  static_cast<const Edge&>(*this) != static_cast<const Edge&>(other);
  1.1045 +      }
  1.1046 +      bool operator<(const Arc &other) const {
  1.1047 +	return _forward < other._forward ||
  1.1048 +	  (_forward == other._forward &&
  1.1049 +	   static_cast<const Edge&>(*this) < static_cast<const Edge&>(other));
  1.1050 +      }
  1.1051 +    };
  1.1052 +
  1.1053 +
  1.1054 +
  1.1055 +    void first(Node& n) const {
  1.1056 +      _digraph->first(n);
  1.1057 +    }
  1.1058 +
  1.1059 +    void next(Node& n) const {
  1.1060 +      _digraph->next(n);
  1.1061 +    }
  1.1062 +
  1.1063 +    void first(Arc& a) const {
  1.1064 +      _digraph->first(a);
  1.1065 +      a._forward = true;
  1.1066 +    }
  1.1067 +
  1.1068 +    void next(Arc& a) const {
  1.1069 +      if (a._forward) {
  1.1070 +	a._forward = false;
  1.1071 +      } else {
  1.1072 +	_digraph->next(a);
  1.1073 +	a._forward = true;
  1.1074 +      }
  1.1075 +    }
  1.1076 +
  1.1077 +    void first(Edge& e) const {
  1.1078 +      _digraph->first(e);
  1.1079 +    }
  1.1080 +
  1.1081 +    void next(Edge& e) const {
  1.1082 +      _digraph->next(e);
  1.1083 +    }
  1.1084 +
  1.1085 +    void firstOut(Arc& a, const Node& n) const {
  1.1086 +      _digraph->firstIn(a, n);
  1.1087 +      if( static_cast<const Edge&>(a) != INVALID ) {
  1.1088 +	a._forward = false;
  1.1089 +      } else {
  1.1090 +	_digraph->firstOut(a, n);
  1.1091 +	a._forward = true;
  1.1092 +      }
  1.1093 +    }
  1.1094 +    void nextOut(Arc &a) const {
  1.1095 +      if (!a._forward) {
  1.1096 +	Node n = _digraph->target(a);
  1.1097 +	_digraph->nextIn(a);
  1.1098 +	if (static_cast<const Edge&>(a) == INVALID ) {
  1.1099 +	  _digraph->firstOut(a, n);
  1.1100 +	  a._forward = true;
  1.1101 +	}
  1.1102 +      }
  1.1103 +      else {
  1.1104 +	_digraph->nextOut(a);
  1.1105 +      }
  1.1106 +    }
  1.1107 +
  1.1108 +    void firstIn(Arc &a, const Node &n) const {
  1.1109 +      _digraph->firstOut(a, n);
  1.1110 +      if (static_cast<const Edge&>(a) != INVALID ) {
  1.1111 +	a._forward = false;
  1.1112 +      } else {
  1.1113 +	_digraph->firstIn(a, n);
  1.1114 +	a._forward = true;
  1.1115 +      }
  1.1116 +    }
  1.1117 +    void nextIn(Arc &a) const {
  1.1118 +      if (!a._forward) {
  1.1119 +	Node n = _digraph->source(a);
  1.1120 +	_digraph->nextOut(a);
  1.1121 +	if( static_cast<const Edge&>(a) == INVALID ) {
  1.1122 +	  _digraph->firstIn(a, n);
  1.1123 +	  a._forward = true;
  1.1124 +	}
  1.1125 +      }
  1.1126 +      else {
  1.1127 +	_digraph->nextIn(a);
  1.1128 +      }
  1.1129 +    }
  1.1130 +
  1.1131 +    void firstInc(Edge &e, bool &d, const Node &n) const {
  1.1132 +      d = true;
  1.1133 +      _digraph->firstOut(e, n);
  1.1134 +      if (e != INVALID) return;
  1.1135 +      d = false;
  1.1136 +      _digraph->firstIn(e, n);
  1.1137 +    }
  1.1138 +
  1.1139 +    void nextInc(Edge &e, bool &d) const {
  1.1140 +      if (d) {
  1.1141 +	Node s = _digraph->source(e);
  1.1142 +	_digraph->nextOut(e);
  1.1143 +	if (e != INVALID) return;
  1.1144 +	d = false;
  1.1145 +	_digraph->firstIn(e, s);
  1.1146 +      } else {
  1.1147 +	_digraph->nextIn(e);
  1.1148 +      }
  1.1149 +    }
  1.1150 +
  1.1151 +    Node u(const Edge& e) const {
  1.1152 +      return _digraph->source(e);
  1.1153 +    }
  1.1154 +
  1.1155 +    Node v(const Edge& e) const {
  1.1156 +      return _digraph->target(e);
  1.1157 +    }
  1.1158 +
  1.1159 +    Node source(const Arc &a) const {
  1.1160 +      return a._forward ? _digraph->source(a) : _digraph->target(a);
  1.1161 +    }
  1.1162 +
  1.1163 +    Node target(const Arc &a) const {
  1.1164 +      return a._forward ? _digraph->target(a) : _digraph->source(a);
  1.1165 +    }
  1.1166 +
  1.1167 +    static Arc direct(const Edge &e, bool d) {
  1.1168 +      return Arc(e, d);
  1.1169 +    }
  1.1170 +    Arc direct(const Edge &e, const Node& n) const {
  1.1171 +      return Arc(e, _digraph->source(e) == n);
  1.1172 +    }
  1.1173 +
  1.1174 +    static bool direction(const Arc &a) { return a._forward; }
  1.1175 +
  1.1176 +    Node nodeFromId(int ix) const { return _digraph->nodeFromId(ix); }
  1.1177 +    Arc arcFromId(int ix) const {
  1.1178 +      return direct(_digraph->arcFromId(ix >> 1), bool(ix & 1));
  1.1179 +    }
  1.1180 +    Edge edgeFromId(int ix) const { return _digraph->arcFromId(ix); }
  1.1181 +
  1.1182 +    int id(const Node &n) const { return _digraph->id(n); }
  1.1183 +    int id(const Arc &a) const {
  1.1184 +      return  (_digraph->id(a) << 1) | (a._forward ? 1 : 0);
  1.1185 +    }
  1.1186 +    int id(const Edge &e) const { return _digraph->id(e); }
  1.1187 +
  1.1188 +    int maxNodeId() const { return _digraph->maxNodeId(); }
  1.1189 +    int maxArcId() const { return (_digraph->maxArcId() << 1) | 1; }
  1.1190 +    int maxEdgeId() const { return _digraph->maxArcId(); }
  1.1191 +
  1.1192 +    Node addNode() { return _digraph->addNode(); }
  1.1193 +    Edge addEdge(const Node& u, const Node& v) { 
  1.1194 +      return _digraph->addArc(u, v); 
  1.1195 +    }
  1.1196 +
  1.1197 +    void erase(const Node& i) { _digraph->erase(i); }
  1.1198 +    void erase(const Edge& i) { _digraph->erase(i); }
  1.1199 +  
  1.1200 +    void clear() { _digraph->clear(); }
  1.1201 +
  1.1202 +    typedef NodeNumTagIndicator<Digraph> NodeNumTag;
  1.1203 +    int nodeNum() const { return 2 * _digraph->arcNum(); }
  1.1204 +    typedef EdgeNumTagIndicator<Digraph> EdgeNumTag;
  1.1205 +    int arcNum() const { return 2 * _digraph->arcNum(); }
  1.1206 +    int edgeNum() const { return _digraph->arcNum(); }
  1.1207 +
  1.1208 +    typedef FindEdgeTagIndicator<Digraph> FindEdgeTag;
  1.1209 +    Arc findArc(Node s, Node t, Arc p = INVALID) const {
  1.1210 +      if (p == INVALID) {
  1.1211 +	Edge arc = _digraph->findArc(s, t);
  1.1212 +	if (arc != INVALID) return direct(arc, true);
  1.1213 +	arc = _digraph->findArc(t, s);
  1.1214 +	if (arc != INVALID) return direct(arc, false);
  1.1215 +      } else if (direction(p)) {
  1.1216 +	Edge arc = _digraph->findArc(s, t, p);
  1.1217 +	if (arc != INVALID) return direct(arc, true);
  1.1218 +	arc = _digraph->findArc(t, s);
  1.1219 +	if (arc != INVALID) return direct(arc, false);	
  1.1220 +      } else {
  1.1221 +	Edge arc = _digraph->findArc(t, s, p);
  1.1222 +	if (arc != INVALID) return direct(arc, false);	      
  1.1223 +      }
  1.1224 +      return INVALID;
  1.1225 +    }
  1.1226 +
  1.1227 +    Edge findEdge(Node s, Node t, Edge p = INVALID) const {
  1.1228 +      if (s != t) {
  1.1229 +        if (p == INVALID) {
  1.1230 +          Edge arc = _digraph->findArc(s, t);
  1.1231 +          if (arc != INVALID) return arc;
  1.1232 +          arc = _digraph->findArc(t, s);
  1.1233 +          if (arc != INVALID) return arc;
  1.1234 +        } else if (_digraph->s(p) == s) {
  1.1235 +          Edge arc = _digraph->findArc(s, t, p);
  1.1236 +          if (arc != INVALID) return arc;
  1.1237 +          arc = _digraph->findArc(t, s);
  1.1238 +          if (arc != INVALID) return arc;	
  1.1239 +        } else {
  1.1240 +          Edge arc = _digraph->findArc(t, s, p);
  1.1241 +          if (arc != INVALID) return arc;	      
  1.1242 +        }
  1.1243 +      } else {
  1.1244 +        return _digraph->findArc(s, t, p);
  1.1245 +      }
  1.1246 +      return INVALID;
  1.1247 +    }
  1.1248 +
  1.1249 +  private:
  1.1250 +    
  1.1251 +    template <typename _Value>
  1.1252 +    class ArcMapBase {
  1.1253 +    private:
  1.1254 +      
  1.1255 +      typedef typename Digraph::template ArcMap<_Value> MapImpl;
  1.1256 +      
  1.1257 +    public:
  1.1258 +
  1.1259 +      typedef typename MapTraits<MapImpl>::ReferenceMapTag ReferenceMapTag;
  1.1260 +
  1.1261 +      typedef _Value Value;
  1.1262 +      typedef Arc Key;
  1.1263 +      
  1.1264 +      ArcMapBase(const Adaptor& adaptor) :
  1.1265 +	_forward(*adaptor._digraph), _backward(*adaptor._digraph) {}
  1.1266 +
  1.1267 +      ArcMapBase(const Adaptor& adaptor, const Value& v) 
  1.1268 +        : _forward(*adaptor._digraph, v), _backward(*adaptor._digraph, v) {}
  1.1269 +      
  1.1270 +      void set(const Arc& a, const Value& v) { 
  1.1271 +	if (direction(a)) {
  1.1272 +	  _forward.set(a, v); 
  1.1273 +        } else { 
  1.1274 +	  _backward.set(a, v);
  1.1275 +        } 
  1.1276 +      }
  1.1277 +
  1.1278 +      typename MapTraits<MapImpl>::ConstReturnValue 
  1.1279 +      operator[](const Arc& a) const { 
  1.1280 +	if (direction(a)) {
  1.1281 +	  return _forward[a]; 
  1.1282 +	} else { 
  1.1283 +	  return _backward[a]; 
  1.1284 +        }
  1.1285 +      }
  1.1286 +
  1.1287 +      typename MapTraits<MapImpl>::ReturnValue 
  1.1288 +      operator[](const Arc& a) { 
  1.1289 +	if (direction(a)) {
  1.1290 +	  return _forward[a]; 
  1.1291 +	} else { 
  1.1292 +	  return _backward[a]; 
  1.1293 +        }
  1.1294 +      }
  1.1295 +
  1.1296 +    protected:
  1.1297 +
  1.1298 +      MapImpl _forward, _backward; 
  1.1299 +
  1.1300 +    };
  1.1301 +
  1.1302 +  public:
  1.1303 +
  1.1304 +    template <typename _Value>
  1.1305 +    class NodeMap : public Digraph::template NodeMap<_Value> {
  1.1306 +    public:
  1.1307 +
  1.1308 +      typedef _Value Value;
  1.1309 +      typedef typename Digraph::template NodeMap<Value> Parent;
  1.1310 +
  1.1311 +      explicit NodeMap(const Adaptor& adaptor) 
  1.1312 +	: Parent(*adaptor._digraph) {}
  1.1313 +
  1.1314 +      NodeMap(const Adaptor& adaptor, const _Value& value)
  1.1315 +	: Parent(*adaptor._digraph, value) { }
  1.1316 +
  1.1317 +    private:
  1.1318 +      NodeMap& operator=(const NodeMap& cmap) {
  1.1319 +        return operator=<NodeMap>(cmap);
  1.1320 +      }
  1.1321 +
  1.1322 +      template <typename CMap>
  1.1323 +      NodeMap& operator=(const CMap& cmap) {
  1.1324 +        Parent::operator=(cmap);
  1.1325 +        return *this;
  1.1326 +      }
  1.1327 +      
  1.1328 +    };
  1.1329 +
  1.1330 +    template <typename _Value>
  1.1331 +    class ArcMap 
  1.1332 +      : public SubMapExtender<Adaptor, ArcMapBase<_Value> > 
  1.1333 +    {
  1.1334 +    public:
  1.1335 +      typedef _Value Value;
  1.1336 +      typedef SubMapExtender<Adaptor, ArcMapBase<Value> > Parent;
  1.1337 +    
  1.1338 +      ArcMap(const Adaptor& adaptor) 
  1.1339 +	: Parent(adaptor) {}
  1.1340 +
  1.1341 +      ArcMap(const Adaptor& adaptor, const Value& value) 
  1.1342 +	: Parent(adaptor, value) {}
  1.1343 +    
  1.1344 +    private:
  1.1345 +      ArcMap& operator=(const ArcMap& cmap) {
  1.1346 +	return operator=<ArcMap>(cmap);
  1.1347 +      }
  1.1348 +    
  1.1349 +      template <typename CMap>
  1.1350 +      ArcMap& operator=(const CMap& cmap) {
  1.1351 +        Parent::operator=(cmap);
  1.1352 +	return *this;
  1.1353 +      }
  1.1354 +    };
  1.1355 +        
  1.1356 +    template <typename _Value>
  1.1357 +    class EdgeMap : public Digraph::template ArcMap<_Value> {
  1.1358 +    public:
  1.1359 +      
  1.1360 +      typedef _Value Value;
  1.1361 +      typedef typename Digraph::template ArcMap<Value> Parent;
  1.1362 +      
  1.1363 +      explicit EdgeMap(const Adaptor& adaptor) 
  1.1364 +	: Parent(*adaptor._digraph) {}
  1.1365 +
  1.1366 +      EdgeMap(const Adaptor& adaptor, const Value& value)
  1.1367 +	: Parent(*adaptor._digraph, value) {}
  1.1368 +
  1.1369 +    private:
  1.1370 +      EdgeMap& operator=(const EdgeMap& cmap) {
  1.1371 +        return operator=<EdgeMap>(cmap);
  1.1372 +      }
  1.1373 +
  1.1374 +      template <typename CMap>
  1.1375 +      EdgeMap& operator=(const CMap& cmap) {
  1.1376 +        Parent::operator=(cmap);
  1.1377 +        return *this;
  1.1378 +      }
  1.1379 +
  1.1380 +    };
  1.1381 +
  1.1382 +    typedef typename ItemSetTraits<Digraph, Node>::ItemNotifier NodeNotifier;
  1.1383 +    NodeNotifier& notifier(Node) const { return _digraph->notifier(Node()); } 
  1.1384 +
  1.1385 +  protected:
  1.1386 +
  1.1387 +    UndirDigraphAdaptorBase() : _digraph(0) {}
  1.1388 +
  1.1389 +    Digraph* _digraph;
  1.1390 +
  1.1391 +    void setDigraph(Digraph& digraph) {
  1.1392 +      _digraph = &digraph;
  1.1393 +    }
  1.1394 +    
  1.1395 +  };
  1.1396 +
  1.1397 +  ///\ingroup graph_adaptors
  1.1398 +  ///
  1.1399 +  /// \brief An graph is made from a directed digraph by an adaptor
  1.1400 +  ///
  1.1401 +  /// This adaptor makes an undirected graph from a directed
  1.1402 +  /// digraph. All arc of the underlying will be showed in the adaptor
  1.1403 +  /// as an edge. Let's see an informal example about using
  1.1404 +  /// this adaptor:
  1.1405 +  ///
  1.1406 +  /// There is a network of the streets of a town. Of course there are
  1.1407 +  /// some one-way street in the town hence the network is a directed
  1.1408 +  /// one. There is a crazy driver who go oppositely in the one-way
  1.1409 +  /// street without moral sense. Of course he can pass this streets
  1.1410 +  /// slower than the regular way, in fact his speed is half of the
  1.1411 +  /// normal speed. How long should he drive to get from a source
  1.1412 +  /// point to the target? Let see the example code which calculate it:
  1.1413 +  ///
  1.1414 +  /// \todo BadCode, SimpleMap does no exists
  1.1415 +  ///\code
  1.1416 +  /// typedef UndirDigraphAdaptor<Digraph> Graph;
  1.1417 +  /// Graph graph(digraph);
  1.1418 +  ///
  1.1419 +  /// typedef SimpleMap<LengthMap> FLengthMap;
  1.1420 +  /// FLengthMap flength(length);
  1.1421 +  ///
  1.1422 +  /// typedef ScaleMap<LengthMap> RLengthMap;
  1.1423 +  /// RLengthMap rlength(length, 2.0);
  1.1424 +  ///
  1.1425 +  /// typedef Graph::CombinedArcMap<FLengthMap, RLengthMap > ULengthMap;
  1.1426 +  /// ULengthMap ulength(flength, rlength);
  1.1427 +  /// 
  1.1428 +  /// Dijkstra<Graph, ULengthMap> dijkstra(graph, ulength);
  1.1429 +  /// std::cout << "Driving time : " << dijkstra.run(src, trg) << std::endl;
  1.1430 +  ///\endcode
  1.1431 +  ///
  1.1432 +  /// The combined arc map makes the length map for the undirected
  1.1433 +  /// graph. It is created from a forward and reverse map. The forward
  1.1434 +  /// map is created from the original length map with a SimpleMap
  1.1435 +  /// adaptor which just makes a read-write map from the reference map
  1.1436 +  /// i.e. it forgets that it can be return reference to values. The
  1.1437 +  /// reverse map is just the scaled original map with the ScaleMap
  1.1438 +  /// adaptor. The combination solves that passing the reverse way
  1.1439 +  /// takes double time than the original. To get the driving time we
  1.1440 +  /// run the dijkstra algorithm on the graph.
  1.1441 +  template<typename _Digraph>
  1.1442 +  class UndirDigraphAdaptor 
  1.1443 +    : public GraphAdaptorExtender<UndirDigraphAdaptorBase<_Digraph> > {
  1.1444 +  public:
  1.1445 +    typedef _Digraph Digraph;
  1.1446 +    typedef GraphAdaptorExtender<UndirDigraphAdaptorBase<Digraph> > Parent;
  1.1447 +  protected:
  1.1448 +    UndirDigraphAdaptor() { }
  1.1449 +  public:
  1.1450 +
  1.1451 +    /// \brief Constructor
  1.1452 +    ///
  1.1453 +    /// Constructor
  1.1454 +    UndirDigraphAdaptor(_Digraph& _digraph) { 
  1.1455 +      setDigraph(_digraph);
  1.1456 +    }
  1.1457 +
  1.1458 +    /// \brief ArcMap combined from two original ArcMap
  1.1459 +    ///
  1.1460 +    /// This class adapts two original digraph ArcMap to
  1.1461 +    /// get an arc map on the adaptor.
  1.1462 +    template <typename _ForwardMap, typename _BackwardMap>
  1.1463 +    class CombinedArcMap {
  1.1464 +    public:
  1.1465 +      
  1.1466 +      typedef _ForwardMap ForwardMap;
  1.1467 +      typedef _BackwardMap BackwardMap;
  1.1468 +
  1.1469 +      typedef typename MapTraits<ForwardMap>::ReferenceMapTag ReferenceMapTag;
  1.1470 +
  1.1471 +      typedef typename ForwardMap::Value Value;
  1.1472 +      typedef typename Parent::Arc Key;
  1.1473 +
  1.1474 +      /// \brief Constructor      
  1.1475 +      ///
  1.1476 +      /// Constructor      
  1.1477 +      CombinedArcMap() : _forward(0), _backward(0) {}
  1.1478 +
  1.1479 +      /// \brief Constructor      
  1.1480 +      ///
  1.1481 +      /// Constructor      
  1.1482 +      CombinedArcMap(ForwardMap& forward, BackwardMap& backward) 
  1.1483 +        : _forward(&forward), _backward(&backward) {}
  1.1484 +      
  1.1485 +
  1.1486 +      /// \brief Sets the value associated with a key.
  1.1487 +      ///
  1.1488 +      /// Sets the value associated with a key.
  1.1489 +      void set(const Key& e, const Value& a) { 
  1.1490 +	if (Parent::direction(e)) {
  1.1491 +	  _forward->set(e, a); 
  1.1492 +        } else { 
  1.1493 +	  _backward->set(e, a);
  1.1494 +        } 
  1.1495 +      }
  1.1496 +
  1.1497 +      /// \brief Returns the value associated with a key.
  1.1498 +      ///
  1.1499 +      /// Returns the value associated with a key.
  1.1500 +      typename MapTraits<ForwardMap>::ConstReturnValue 
  1.1501 +      operator[](const Key& e) const { 
  1.1502 +	if (Parent::direction(e)) {
  1.1503 +	  return (*_forward)[e]; 
  1.1504 +	} else { 
  1.1505 +	  return (*_backward)[e]; 
  1.1506 +        }
  1.1507 +      }
  1.1508 +
  1.1509 +      /// \brief Returns the value associated with a key.
  1.1510 +      ///
  1.1511 +      /// Returns the value associated with a key.
  1.1512 +      typename MapTraits<ForwardMap>::ReturnValue 
  1.1513 +      operator[](const Key& e) { 
  1.1514 +	if (Parent::direction(e)) {
  1.1515 +	  return (*_forward)[e]; 
  1.1516 +	} else { 
  1.1517 +	  return (*_backward)[e]; 
  1.1518 +        }
  1.1519 +      }
  1.1520 +
  1.1521 +      /// \brief Sets the forward map
  1.1522 +      ///
  1.1523 +      /// Sets the forward map
  1.1524 +      void setForwardMap(ForwardMap& forward) {
  1.1525 +        _forward = &forward;
  1.1526 +      }
  1.1527 +
  1.1528 +      /// \brief Sets the backward map
  1.1529 +      ///
  1.1530 +      /// Sets the backward map
  1.1531 +      void setBackwardMap(BackwardMap& backward) {
  1.1532 +        _backward = &backward;
  1.1533 +      }
  1.1534 +
  1.1535 +    protected:
  1.1536 +
  1.1537 +      ForwardMap* _forward;
  1.1538 +      BackwardMap* _backward; 
  1.1539 +
  1.1540 +    };
  1.1541 +
  1.1542 +  };
  1.1543 +
  1.1544 +  /// \brief Just gives back an undir digraph adaptor
  1.1545 +  ///
  1.1546 +  /// Just gives back an undir digraph adaptor
  1.1547 +  template<typename Digraph>
  1.1548 +  UndirDigraphAdaptor<const Digraph>
  1.1549 +  undirDigraphAdaptor(const Digraph& digraph) {
  1.1550 +    return UndirDigraphAdaptor<const Digraph>(digraph);
  1.1551 +  }
  1.1552 +
  1.1553 +  template<typename _Digraph, 
  1.1554 +	   typename _CapacityMap = typename _Digraph::template ArcMap<int>, 
  1.1555 +	   typename _FlowMap = _CapacityMap, 
  1.1556 +           typename _Tolerance = Tolerance<typename _CapacityMap::Value> >
  1.1557 +  class ResForwardFilter {
  1.1558 +  public:
  1.1559 +
  1.1560 +    typedef _Digraph Digraph;
  1.1561 +    typedef _CapacityMap CapacityMap;
  1.1562 +    typedef _FlowMap FlowMap;
  1.1563 +    typedef _Tolerance Tolerance;
  1.1564 +
  1.1565 +    typedef typename Digraph::Arc Key;
  1.1566 +    typedef bool Value;
  1.1567 +
  1.1568 +  private:
  1.1569 +
  1.1570 +    const CapacityMap* _capacity;
  1.1571 +    const FlowMap* _flow;
  1.1572 +    Tolerance _tolerance;
  1.1573 +  public:
  1.1574 +
  1.1575 +    ResForwardFilter(const CapacityMap& capacity, const FlowMap& flow,
  1.1576 +                     const Tolerance& tolerance = Tolerance()) 
  1.1577 +      : _capacity(&capacity), _flow(&flow), _tolerance(tolerance) { }
  1.1578 +
  1.1579 +    ResForwardFilter(const Tolerance& tolerance = Tolerance()) 
  1.1580 +      : _capacity(0), _flow(0), _tolerance(tolerance)  { }
  1.1581 +
  1.1582 +    void setCapacity(const CapacityMap& capacity) { _capacity = &capacity; }
  1.1583 +    void setFlow(const FlowMap& flow) { _flow = &flow; }
  1.1584 +
  1.1585 +    bool operator[](const typename Digraph::Arc& a) const {
  1.1586 +      return _tolerance.positive((*_capacity)[a] - (*_flow)[a]);
  1.1587 +    }
  1.1588 +  };
  1.1589 +
  1.1590 +  template<typename _Digraph, 
  1.1591 +	   typename _CapacityMap = typename _Digraph::template ArcMap<int>, 
  1.1592 +	   typename _FlowMap = _CapacityMap, 
  1.1593 +           typename _Tolerance = Tolerance<typename _CapacityMap::Value> >
  1.1594 +  class ResBackwardFilter {
  1.1595 +  public:
  1.1596 +
  1.1597 +    typedef _Digraph Digraph;
  1.1598 +    typedef _CapacityMap CapacityMap;
  1.1599 +    typedef _FlowMap FlowMap;
  1.1600 +    typedef _Tolerance Tolerance;
  1.1601 +
  1.1602 +    typedef typename Digraph::Arc Key;
  1.1603 +    typedef bool Value;
  1.1604 +
  1.1605 +  private:
  1.1606 +
  1.1607 +    const CapacityMap* _capacity;
  1.1608 +    const FlowMap* _flow;
  1.1609 +    Tolerance _tolerance;
  1.1610 +
  1.1611 +  public:
  1.1612 +
  1.1613 +    ResBackwardFilter(const CapacityMap& capacity, const FlowMap& flow,
  1.1614 +                      const Tolerance& tolerance = Tolerance())
  1.1615 +      : _capacity(&capacity), _flow(&flow), _tolerance(tolerance) { }
  1.1616 +    ResBackwardFilter(const Tolerance& tolerance = Tolerance())
  1.1617 +      : _capacity(0), _flow(0), _tolerance(tolerance) { }
  1.1618 +
  1.1619 +    void setCapacity(const CapacityMap& capacity) { _capacity = &capacity; }
  1.1620 +    void setFlow(const FlowMap& flow) { _flow = &flow; }
  1.1621 +
  1.1622 +    bool operator[](const typename Digraph::Arc& a) const {
  1.1623 +      return _tolerance.positive((*_flow)[a]);
  1.1624 +    }
  1.1625 +  };
  1.1626 +
  1.1627 +  
  1.1628 +  ///\ingroup graph_adaptors
  1.1629 +  ///
  1.1630 +  ///\brief An adaptor for composing the residual graph for directed
  1.1631 +  ///flow and circulation problems.
  1.1632 +  ///
  1.1633 +  ///An adaptor for composing the residual graph for directed flow and
  1.1634 +  ///circulation problems.  Let \f$ G=(V, A) \f$ be a directed digraph
  1.1635 +  ///and let \f$ F \f$ be a number type. Let moreover \f$ f,c:A\to F
  1.1636 +  ///\f$, be functions on the arc-set.
  1.1637 +  ///
  1.1638 +  ///In the appications of ResDigraphAdaptor, \f$ f \f$ usually stands
  1.1639 +  ///for a flow and \f$ c \f$ for a capacity function.  Suppose that a
  1.1640 +  ///graph instance \c g of type \c ListDigraph implements \f$ G \f$.
  1.1641 +  ///
  1.1642 +  ///\code 
  1.1643 +  ///  ListDigraph g;
  1.1644 +  ///\endcode 
  1.1645 +  ///
  1.1646 +  ///Then ResDigraphAdaptor implements the digraph structure with
  1.1647 +  /// node-set \f$ V \f$ and arc-set \f$ A_{forward}\cup A_{backward}
  1.1648 +  /// \f$, where \f$ A_{forward}=\{uv : uv\in A, f(uv)<c(uv)\} \f$ and
  1.1649 +  /// \f$ A_{backward}=\{vu : uv\in A, f(uv)>0\} \f$, i.e. the so
  1.1650 +  /// called residual graph.  When we take the union \f$
  1.1651 +  /// A_{forward}\cup A_{backward} \f$, multilicities are counted,
  1.1652 +  /// i.e.  if an arc is in both \f$ A_{forward} \f$ and \f$
  1.1653 +  /// A_{backward} \f$, then in the adaptor it appears twice. The
  1.1654 +  /// following code shows how such an instance can be constructed.
  1.1655 +  ///
  1.1656 +  ///\code 
  1.1657 +  ///  typedef ListDigraph Digraph; 
  1.1658 +  ///  IntArcMap f(g), c(g);
  1.1659 +  ///  ResDigraphAdaptor<Digraph, int, IntArcMap, IntArcMap> ga(g); 
  1.1660 +  ///\endcode
  1.1661 +  template<typename _Digraph, 
  1.1662 +	   typename _CapacityMap = typename _Digraph::template ArcMap<int>, 
  1.1663 +	   typename _FlowMap = _CapacityMap,
  1.1664 +           typename _Tolerance = Tolerance<typename _CapacityMap::Value> >
  1.1665 +  class ResDigraphAdaptor : 
  1.1666 +    public ArcSubDigraphAdaptor< 
  1.1667 +    UndirDigraphAdaptor<const _Digraph>, 
  1.1668 +    typename UndirDigraphAdaptor<const _Digraph>::template CombinedArcMap<
  1.1669 +      ResForwardFilter<const _Digraph, _CapacityMap, _FlowMap>,  
  1.1670 +      ResBackwardFilter<const _Digraph, _CapacityMap, _FlowMap> > > {
  1.1671 +  public:
  1.1672 +
  1.1673 +    typedef _Digraph Digraph;
  1.1674 +    typedef _CapacityMap CapacityMap;
  1.1675 +    typedef _FlowMap FlowMap;
  1.1676 +    typedef _Tolerance Tolerance;
  1.1677 +
  1.1678 +    typedef typename CapacityMap::Value Value;
  1.1679 +    typedef ResDigraphAdaptor Adaptor;
  1.1680 +
  1.1681 +  protected:
  1.1682 +
  1.1683 +    typedef UndirDigraphAdaptor<const Digraph> UndirDigraph;
  1.1684 +
  1.1685 +    typedef ResForwardFilter<const Digraph, CapacityMap, FlowMap> 
  1.1686 +    ForwardFilter;
  1.1687 +
  1.1688 +    typedef ResBackwardFilter<const Digraph, CapacityMap, FlowMap> 
  1.1689 +    BackwardFilter;
  1.1690 +
  1.1691 +    typedef typename UndirDigraph::
  1.1692 +    template CombinedArcMap<ForwardFilter, BackwardFilter> ArcFilter;
  1.1693 +
  1.1694 +    typedef ArcSubDigraphAdaptor<UndirDigraph, ArcFilter> Parent;
  1.1695 +
  1.1696 +    const CapacityMap* _capacity;
  1.1697 +    FlowMap* _flow;
  1.1698 +
  1.1699 +    UndirDigraph _graph;
  1.1700 +    ForwardFilter _forward_filter;
  1.1701 +    BackwardFilter _backward_filter;
  1.1702 +    ArcFilter _arc_filter;
  1.1703 +
  1.1704 +    void setCapacityMap(const CapacityMap& capacity) {
  1.1705 +      _capacity = &capacity;
  1.1706 +      _forward_filter.setCapacity(capacity);
  1.1707 +      _backward_filter.setCapacity(capacity);
  1.1708 +    }
  1.1709 +
  1.1710 +    void setFlowMap(FlowMap& flow) {
  1.1711 +      _flow = &flow;
  1.1712 +      _forward_filter.setFlow(flow);
  1.1713 +      _backward_filter.setFlow(flow);
  1.1714 +    }
  1.1715 +
  1.1716 +  public:
  1.1717 +
  1.1718 +    /// \brief Constructor of the residual digraph.
  1.1719 +    ///
  1.1720 +    /// Constructor of the residual graph. The parameters are the digraph type,
  1.1721 +    /// the flow map, the capacity map and a tolerance object.
  1.1722 +    ResDigraphAdaptor(const Digraph& digraph, const CapacityMap& capacity, 
  1.1723 +                    FlowMap& flow, const Tolerance& tolerance = Tolerance()) 
  1.1724 +      : Parent(), _capacity(&capacity), _flow(&flow), _graph(digraph),
  1.1725 +        _forward_filter(capacity, flow, tolerance), 
  1.1726 +        _backward_filter(capacity, flow, tolerance),
  1.1727 +        _arc_filter(_forward_filter, _backward_filter)
  1.1728 +    {
  1.1729 +      Parent::setDigraph(_graph);
  1.1730 +      Parent::setArcFilterMap(_arc_filter);
  1.1731 +    }
  1.1732 +
  1.1733 +    typedef typename Parent::Arc Arc;
  1.1734 +
  1.1735 +    /// \brief Gives back the residual capacity of the arc.
  1.1736 +    ///
  1.1737 +    /// Gives back the residual capacity of the arc.
  1.1738 +    Value rescap(const Arc& arc) const {
  1.1739 +      if (UndirDigraph::direction(arc)) {
  1.1740 +        return (*_capacity)[arc] - (*_flow)[arc]; 
  1.1741 +      } else {
  1.1742 +        return (*_flow)[arc];
  1.1743 +      }
  1.1744 +    } 
  1.1745 +
  1.1746 +    /// \brief Augment on the given arc in the residual digraph.
  1.1747 +    ///
  1.1748 +    /// Augment on the given arc in the residual digraph. It increase
  1.1749 +    /// or decrease the flow on the original arc depend on the direction
  1.1750 +    /// of the residual arc.
  1.1751 +    void augment(const Arc& e, const Value& a) const {
  1.1752 +      if (UndirDigraph::direction(e)) {
  1.1753 +        _flow->set(e, (*_flow)[e] + a);
  1.1754 +      } else {  
  1.1755 +        _flow->set(e, (*_flow)[e] - a);
  1.1756 +      }
  1.1757 +    }
  1.1758 +
  1.1759 +    /// \brief Returns the direction of the arc.
  1.1760 +    ///
  1.1761 +    /// Returns true when the arc is same oriented as the original arc.
  1.1762 +    static bool forward(const Arc& e) {
  1.1763 +      return UndirDigraph::direction(e);
  1.1764 +    }
  1.1765 +
  1.1766 +    /// \brief Returns the direction of the arc.
  1.1767 +    ///
  1.1768 +    /// Returns true when the arc is opposite oriented as the original arc.
  1.1769 +    static bool backward(const Arc& e) {
  1.1770 +      return !UndirDigraph::direction(e);
  1.1771 +    }
  1.1772 +
  1.1773 +    /// \brief Gives back the forward oriented residual arc.
  1.1774 +    ///
  1.1775 +    /// Gives back the forward oriented residual arc.
  1.1776 +    static Arc forward(const typename Digraph::Arc& e) {
  1.1777 +      return UndirDigraph::direct(e, true);
  1.1778 +    }
  1.1779 +
  1.1780 +    /// \brief Gives back the backward oriented residual arc.
  1.1781 +    ///
  1.1782 +    /// Gives back the backward oriented residual arc.
  1.1783 +    static Arc backward(const typename Digraph::Arc& e) {
  1.1784 +      return UndirDigraph::direct(e, false);
  1.1785 +    }
  1.1786 +
  1.1787 +    /// \brief Residual capacity map.
  1.1788 +    ///
  1.1789 +    /// In generic residual digraphs the residual capacity can be obtained 
  1.1790 +    /// as a map. 
  1.1791 +    class ResCap {
  1.1792 +    protected:
  1.1793 +      const Adaptor* _adaptor;
  1.1794 +    public:
  1.1795 +      typedef Arc Key;
  1.1796 +      typedef typename _CapacityMap::Value Value;
  1.1797 +
  1.1798 +      ResCap(const Adaptor& adaptor) : _adaptor(&adaptor) {}
  1.1799 +      
  1.1800 +      Value operator[](const Arc& e) const {
  1.1801 +        return _adaptor->rescap(e);
  1.1802 +      }
  1.1803 +      
  1.1804 +    };
  1.1805 +
  1.1806 +  };
  1.1807 +
  1.1808 +  /// \brief Base class for split digraph adaptor
  1.1809 +  ///
  1.1810 +  /// Base class of split digraph adaptor. In most case you do not need to
  1.1811 +  /// use it directly but the documented member functions of this class can 
  1.1812 +  /// be used with the SplitDigraphAdaptor class.
  1.1813 +  /// \sa SplitDigraphAdaptor
  1.1814 +  template <typename _Digraph>
  1.1815 +  class SplitDigraphAdaptorBase {
  1.1816 +  public:
  1.1817 +
  1.1818 +    typedef _Digraph Digraph;
  1.1819 +    typedef DigraphAdaptorBase<const _Digraph> Parent;
  1.1820 +    typedef SplitDigraphAdaptorBase Adaptor;
  1.1821 +
  1.1822 +    typedef typename Digraph::Node DigraphNode;
  1.1823 +    typedef typename Digraph::Arc DigraphArc;
  1.1824 +
  1.1825 +    class Node;
  1.1826 +    class Arc;
  1.1827 +
  1.1828 +  private:
  1.1829 +
  1.1830 +    template <typename T> class NodeMapBase;
  1.1831 +    template <typename T> class ArcMapBase;
  1.1832 +
  1.1833 +  public:
  1.1834 +    
  1.1835 +    class Node : public DigraphNode {
  1.1836 +      friend class SplitDigraphAdaptorBase;
  1.1837 +      template <typename T> friend class NodeMapBase;
  1.1838 +    private:
  1.1839 +
  1.1840 +      bool _in;
  1.1841 +      Node(DigraphNode node, bool in)
  1.1842 +	: DigraphNode(node), _in(in) {}
  1.1843 +      
  1.1844 +    public:
  1.1845 +
  1.1846 +      Node() {}
  1.1847 +      Node(Invalid) : DigraphNode(INVALID), _in(true) {}
  1.1848 +
  1.1849 +      bool operator==(const Node& node) const {
  1.1850 +	return DigraphNode::operator==(node) && _in == node._in;
  1.1851 +      }
  1.1852 +      
  1.1853 +      bool operator!=(const Node& node) const {
  1.1854 +	return !(*this == node);
  1.1855 +      }
  1.1856 +      
  1.1857 +      bool operator<(const Node& node) const {
  1.1858 +	return DigraphNode::operator<(node) || 
  1.1859 +	  (DigraphNode::operator==(node) && _in < node._in);
  1.1860 +      }
  1.1861 +    };
  1.1862 +
  1.1863 +    class Arc {
  1.1864 +      friend class SplitDigraphAdaptorBase;
  1.1865 +      template <typename T> friend class ArcMapBase;
  1.1866 +    private:
  1.1867 +      typedef BiVariant<DigraphArc, DigraphNode> ArcImpl;
  1.1868 +
  1.1869 +      explicit Arc(const DigraphArc& arc) : _item(arc) {}
  1.1870 +      explicit Arc(const DigraphNode& node) : _item(node) {}
  1.1871 +      
  1.1872 +      ArcImpl _item;
  1.1873 +
  1.1874 +    public:
  1.1875 +      Arc() {}
  1.1876 +      Arc(Invalid) : _item(DigraphArc(INVALID)) {}
  1.1877 +
  1.1878 +      bool operator==(const Arc& arc) const {
  1.1879 +        if (_item.firstState()) {
  1.1880 +          if (arc._item.firstState()) {
  1.1881 +            return _item.first() == arc._item.first();
  1.1882 +          }
  1.1883 +        } else {
  1.1884 +          if (arc._item.secondState()) {
  1.1885 +            return _item.second() == arc._item.second();
  1.1886 +          }
  1.1887 +        }
  1.1888 +        return false;
  1.1889 +      }
  1.1890 +      
  1.1891 +      bool operator!=(const Arc& arc) const {
  1.1892 +	return !(*this == arc);
  1.1893 +      }
  1.1894 +      
  1.1895 +      bool operator<(const Arc& arc) const {
  1.1896 +        if (_item.firstState()) {
  1.1897 +          if (arc._item.firstState()) {
  1.1898 +            return _item.first() < arc._item.first();
  1.1899 +          }
  1.1900 +          return false;
  1.1901 +        } else {
  1.1902 +          if (arc._item.secondState()) {
  1.1903 +            return _item.second() < arc._item.second();
  1.1904 +          }
  1.1905 +          return true;
  1.1906 +        }
  1.1907 +      }
  1.1908 +
  1.1909 +      operator DigraphArc() const { return _item.first(); }
  1.1910 +      operator DigraphNode() const { return _item.second(); }
  1.1911 +
  1.1912 +    };
  1.1913 +
  1.1914 +    void first(Node& n) const {
  1.1915 +      _digraph->first(n);
  1.1916 +      n._in = true;
  1.1917 +    }
  1.1918 +
  1.1919 +    void next(Node& n) const {
  1.1920 +      if (n._in) {
  1.1921 +	n._in = false;
  1.1922 +      } else {
  1.1923 +	n._in = true;
  1.1924 +	_digraph->next(n);
  1.1925 +      }
  1.1926 +    }
  1.1927 +
  1.1928 +    void first(Arc& e) const {
  1.1929 +      e._item.setSecond();
  1.1930 +      _digraph->first(e._item.second());
  1.1931 +      if (e._item.second() == INVALID) {
  1.1932 +        e._item.setFirst();
  1.1933 +	_digraph->first(e._item.first());
  1.1934 +      }
  1.1935 +    }
  1.1936 +
  1.1937 +    void next(Arc& e) const {
  1.1938 +      if (e._item.secondState()) {
  1.1939 +	_digraph->next(e._item.second());
  1.1940 +        if (e._item.second() == INVALID) {
  1.1941 +          e._item.setFirst();
  1.1942 +          _digraph->first(e._item.first());
  1.1943 +        }
  1.1944 +      } else {
  1.1945 +	_digraph->next(e._item.first());
  1.1946 +      }      
  1.1947 +    }
  1.1948 +
  1.1949 +    void firstOut(Arc& e, const Node& n) const {
  1.1950 +      if (n._in) {
  1.1951 +        e._item.setSecond(n);
  1.1952 +      } else {
  1.1953 +        e._item.setFirst();
  1.1954 +	_digraph->firstOut(e._item.first(), n);
  1.1955 +      }
  1.1956 +    }
  1.1957 +
  1.1958 +    void nextOut(Arc& e) const {
  1.1959 +      if (!e._item.firstState()) {
  1.1960 +	e._item.setFirst(INVALID);
  1.1961 +      } else {
  1.1962 +	_digraph->nextOut(e._item.first());
  1.1963 +      }      
  1.1964 +    }
  1.1965 +
  1.1966 +    void firstIn(Arc& e, const Node& n) const {
  1.1967 +      if (!n._in) {
  1.1968 +        e._item.setSecond(n);        
  1.1969 +      } else {
  1.1970 +        e._item.setFirst();
  1.1971 +	_digraph->firstIn(e._item.first(), n);
  1.1972 +      }
  1.1973 +    }
  1.1974 +
  1.1975 +    void nextIn(Arc& e) const {
  1.1976 +      if (!e._item.firstState()) {
  1.1977 +	e._item.setFirst(INVALID);
  1.1978 +      } else {
  1.1979 +	_digraph->nextIn(e._item.first());
  1.1980 +      }
  1.1981 +    }
  1.1982 +
  1.1983 +    Node source(const Arc& e) const {
  1.1984 +      if (e._item.firstState()) {
  1.1985 +	return Node(_digraph->source(e._item.first()), false);
  1.1986 +      } else {
  1.1987 +	return Node(e._item.second(), true);
  1.1988 +      }
  1.1989 +    }
  1.1990 +
  1.1991 +    Node target(const Arc& e) const {
  1.1992 +      if (e._item.firstState()) {
  1.1993 +	return Node(_digraph->target(e._item.first()), true);
  1.1994 +      } else {
  1.1995 +	return Node(e._item.second(), false);
  1.1996 +      }
  1.1997 +    }
  1.1998 +
  1.1999 +    int id(const Node& n) const {
  1.2000 +      return (_digraph->id(n) << 1) | (n._in ? 0 : 1);
  1.2001 +    }
  1.2002 +    Node nodeFromId(int ix) const {
  1.2003 +      return Node(_digraph->nodeFromId(ix >> 1), (ix & 1) == 0);
  1.2004 +    }
  1.2005 +    int maxNodeId() const {
  1.2006 +      return 2 * _digraph->maxNodeId() + 1;
  1.2007 +    }
  1.2008 +
  1.2009 +    int id(const Arc& e) const {
  1.2010 +      if (e._item.firstState()) {
  1.2011 +        return _digraph->id(e._item.first()) << 1;
  1.2012 +      } else {
  1.2013 +        return (_digraph->id(e._item.second()) << 1) | 1;
  1.2014 +      }
  1.2015 +    }
  1.2016 +    Arc arcFromId(int ix) const {
  1.2017 +      if ((ix & 1) == 0) {
  1.2018 +        return Arc(_digraph->arcFromId(ix >> 1));
  1.2019 +      } else {
  1.2020 +        return Arc(_digraph->nodeFromId(ix >> 1));
  1.2021 +      }
  1.2022 +    }
  1.2023 +    int maxArcId() const {
  1.2024 +      return std::max(_digraph->maxNodeId() << 1, 
  1.2025 +                      (_digraph->maxArcId() << 1) | 1);
  1.2026 +    }
  1.2027 +
  1.2028 +    /// \brief Returns true when the node is in-node.
  1.2029 +    ///
  1.2030 +    /// Returns true when the node is in-node.
  1.2031 +    static bool inNode(const Node& n) {
  1.2032 +      return n._in;
  1.2033 +    }
  1.2034 +
  1.2035 +    /// \brief Returns true when the node is out-node.
  1.2036 +    ///
  1.2037 +    /// Returns true when the node is out-node.
  1.2038 +    static bool outNode(const Node& n) {
  1.2039 +      return !n._in;
  1.2040 +    }
  1.2041 +
  1.2042 +    /// \brief Returns true when the arc is arc in the original digraph.
  1.2043 +    ///
  1.2044 +    /// Returns true when the arc is arc in the original digraph.
  1.2045 +    static bool origArc(const Arc& e) {
  1.2046 +      return e._item.firstState();
  1.2047 +    }
  1.2048 +
  1.2049 +    /// \brief Returns true when the arc binds an in-node and an out-node.
  1.2050 +    ///
  1.2051 +    /// Returns true when the arc binds an in-node and an out-node.
  1.2052 +    static bool bindArc(const Arc& e) {
  1.2053 +      return e._item.secondState();
  1.2054 +    }
  1.2055 +
  1.2056 +    /// \brief Gives back the in-node created from the \c node.
  1.2057 +    ///
  1.2058 +    /// Gives back the in-node created from the \c node.
  1.2059 +    static Node inNode(const DigraphNode& n) {
  1.2060 +      return Node(n, true);
  1.2061 +    }
  1.2062 +
  1.2063 +    /// \brief Gives back the out-node created from the \c node.
  1.2064 +    ///
  1.2065 +    /// Gives back the out-node created from the \c node.
  1.2066 +    static Node outNode(const DigraphNode& n) {
  1.2067 +      return Node(n, false);
  1.2068 +    }
  1.2069 +
  1.2070 +    /// \brief Gives back the arc binds the two part of the node.
  1.2071 +    /// 
  1.2072 +    /// Gives back the arc binds the two part of the node.
  1.2073 +    static Arc arc(const DigraphNode& n) {
  1.2074 +      return Arc(n);
  1.2075 +    }
  1.2076 +
  1.2077 +    /// \brief Gives back the arc of the original arc.
  1.2078 +    /// 
  1.2079 +    /// Gives back the arc of the original arc.
  1.2080 +    static Arc arc(const DigraphArc& e) {
  1.2081 +      return Arc(e);
  1.2082 +    }
  1.2083 +
  1.2084 +    typedef True NodeNumTag;
  1.2085 +
  1.2086 +    int nodeNum() const {
  1.2087 +      return  2 * countNodes(*_digraph);
  1.2088 +    }
  1.2089 +
  1.2090 +    typedef True EdgeNumTag;
  1.2091 +    int arcNum() const {
  1.2092 +      return countArcs(*_digraph) + countNodes(*_digraph);
  1.2093 +    }
  1.2094 +
  1.2095 +    typedef True FindEdgeTag;
  1.2096 +    Arc findArc(const Node& u, const Node& v, 
  1.2097 +		const Arc& prev = INVALID) const {
  1.2098 +      if (inNode(u)) {
  1.2099 +        if (outNode(v)) {
  1.2100 +          if (static_cast<const DigraphNode&>(u) == 
  1.2101 +              static_cast<const DigraphNode&>(v) && prev == INVALID) {
  1.2102 +            return Arc(u);
  1.2103 +          }
  1.2104 +        }
  1.2105 +      } else {
  1.2106 +        if (inNode(v)) {
  1.2107 +          return Arc(::lemon::findArc(*_digraph, u, v, prev));
  1.2108 +        }
  1.2109 +      }
  1.2110 +      return INVALID;
  1.2111 +    }
  1.2112 +
  1.2113 +  private:
  1.2114 +    
  1.2115 +    template <typename _Value>
  1.2116 +    class NodeMapBase 
  1.2117 +      : public MapTraits<typename Parent::template NodeMap<_Value> > {
  1.2118 +      typedef typename Parent::template NodeMap<_Value> NodeImpl;
  1.2119 +    public:
  1.2120 +      typedef Node Key;
  1.2121 +      typedef _Value Value;
  1.2122 +      
  1.2123 +      NodeMapBase(const Adaptor& adaptor) 
  1.2124 +	: _in_map(*adaptor._digraph), _out_map(*adaptor._digraph) {}
  1.2125 +      NodeMapBase(const Adaptor& adaptor, const Value& value) 
  1.2126 +	: _in_map(*adaptor._digraph, value), 
  1.2127 +	  _out_map(*adaptor._digraph, value) {}
  1.2128 +
  1.2129 +      void set(const Node& key, const Value& val) {
  1.2130 +	if (Adaptor::inNode(key)) { _in_map.set(key, val); }
  1.2131 +	else {_out_map.set(key, val); }
  1.2132 +      }
  1.2133 +      
  1.2134 +      typename MapTraits<NodeImpl>::ReturnValue 
  1.2135 +      operator[](const Node& key) {
  1.2136 +	if (Adaptor::inNode(key)) { return _in_map[key]; }
  1.2137 +	else { return _out_map[key]; }
  1.2138 +      }
  1.2139 +
  1.2140 +      typename MapTraits<NodeImpl>::ConstReturnValue
  1.2141 +      operator[](const Node& key) const {
  1.2142 +	if (Adaptor::inNode(key)) { return _in_map[key]; }
  1.2143 +	else { return _out_map[key]; }
  1.2144 +      }
  1.2145 +
  1.2146 +    private:
  1.2147 +      NodeImpl _in_map, _out_map;
  1.2148 +    };
  1.2149 +
  1.2150 +    template <typename _Value>
  1.2151 +    class ArcMapBase 
  1.2152 +      : public MapTraits<typename Parent::template ArcMap<_Value> > {
  1.2153 +      typedef typename Parent::template ArcMap<_Value> ArcImpl;
  1.2154 +      typedef typename Parent::template NodeMap<_Value> NodeImpl;
  1.2155 +    public:
  1.2156 +      typedef Arc Key;
  1.2157 +      typedef _Value Value;
  1.2158 +
  1.2159 +      ArcMapBase(const Adaptor& adaptor) 
  1.2160 +	: _arc_map(*adaptor._digraph), _node_map(*adaptor._digraph) {}
  1.2161 +      ArcMapBase(const Adaptor& adaptor, const Value& value) 
  1.2162 +	: _arc_map(*adaptor._digraph, value), 
  1.2163 +	  _node_map(*adaptor._digraph, value) {}
  1.2164 +
  1.2165 +      void set(const Arc& key, const Value& val) {
  1.2166 +	if (Adaptor::origArc(key)) { 
  1.2167 +          _arc_map.set(key._item.first(), val); 
  1.2168 +        } else {
  1.2169 +          _node_map.set(key._item.second(), val); 
  1.2170 +        }
  1.2171 +      }
  1.2172 +      
  1.2173 +      typename MapTraits<ArcImpl>::ReturnValue
  1.2174 +      operator[](const Arc& key) {
  1.2175 +	if (Adaptor::origArc(key)) { 
  1.2176 +          return _arc_map[key._item.first()];
  1.2177 +        } else {
  1.2178 +          return _node_map[key._item.second()];
  1.2179 +        }
  1.2180 +      }
  1.2181 +
  1.2182 +      typename MapTraits<ArcImpl>::ConstReturnValue
  1.2183 +      operator[](const Arc& key) const {
  1.2184 +	if (Adaptor::origArc(key)) { 
  1.2185 +          return _arc_map[key._item.first()];
  1.2186 +        } else {
  1.2187 +          return _node_map[key._item.second()];
  1.2188 +        }
  1.2189 +      }
  1.2190 +
  1.2191 +    private:
  1.2192 +      ArcImpl _arc_map;
  1.2193 +      NodeImpl _node_map;
  1.2194 +    };
  1.2195 +
  1.2196 +  public:
  1.2197 +
  1.2198 +    template <typename _Value>
  1.2199 +    class NodeMap 
  1.2200 +      : public SubMapExtender<Adaptor, NodeMapBase<_Value> > 
  1.2201 +    {
  1.2202 +    public:
  1.2203 +      typedef _Value Value;
  1.2204 +      typedef SubMapExtender<Adaptor, NodeMapBase<Value> > Parent;
  1.2205 +    
  1.2206 +      NodeMap(const Adaptor& adaptor) 
  1.2207 +	: Parent(adaptor) {}
  1.2208 +
  1.2209 +      NodeMap(const Adaptor& adaptor, const Value& value) 
  1.2210 +	: Parent(adaptor, value) {}
  1.2211 +    
  1.2212 +    private:
  1.2213 +      NodeMap& operator=(const NodeMap& cmap) {
  1.2214 +	return operator=<NodeMap>(cmap);
  1.2215 +      }
  1.2216 +    
  1.2217 +      template <typename CMap>
  1.2218 +      NodeMap& operator=(const CMap& cmap) {
  1.2219 +        Parent::operator=(cmap);
  1.2220 +	return *this;
  1.2221 +      }
  1.2222 +    };
  1.2223 +
  1.2224 +    template <typename _Value>
  1.2225 +    class ArcMap 
  1.2226 +      : public SubMapExtender<Adaptor, ArcMapBase<_Value> > 
  1.2227 +    {
  1.2228 +    public:
  1.2229 +      typedef _Value Value;
  1.2230 +      typedef SubMapExtender<Adaptor, ArcMapBase<Value> > Parent;
  1.2231 +    
  1.2232 +      ArcMap(const Adaptor& adaptor) 
  1.2233 +	: Parent(adaptor) {}
  1.2234 +
  1.2235 +      ArcMap(const Adaptor& adaptor, const Value& value) 
  1.2236 +	: Parent(adaptor, value) {}
  1.2237 +    
  1.2238 +    private:
  1.2239 +      ArcMap& operator=(const ArcMap& cmap) {
  1.2240 +	return operator=<ArcMap>(cmap);
  1.2241 +      }
  1.2242 +    
  1.2243 +      template <typename CMap>
  1.2244 +      ArcMap& operator=(const CMap& cmap) {
  1.2245 +        Parent::operator=(cmap);
  1.2246 +	return *this;
  1.2247 +      }
  1.2248 +    };
  1.2249 +
  1.2250 +  protected:
  1.2251 +
  1.2252 +    SplitDigraphAdaptorBase() : _digraph(0) {}
  1.2253 +
  1.2254 +    Digraph* _digraph;
  1.2255 +
  1.2256 +    void setDigraph(Digraph& digraph) {
  1.2257 +      _digraph = &digraph;
  1.2258 +    }
  1.2259 +    
  1.2260 +  };
  1.2261 +
  1.2262 +  /// \ingroup graph_adaptors
  1.2263 +  ///
  1.2264 +  /// \brief Split digraph adaptor class
  1.2265 +  /// 
  1.2266 +  /// This is an digraph adaptor which splits all node into an in-node
  1.2267 +  /// and an out-node. Formaly, the adaptor replaces each \f$ u \f$
  1.2268 +  /// node in the digraph with two node, \f$ u_{in} \f$ node and 
  1.2269 +  /// \f$ u_{out} \f$ node. If there is an \f$ (v, u) \f$ arc in the 
  1.2270 +  /// original digraph the new target of the arc will be \f$ u_{in} \f$ and
  1.2271 +  /// similarly the source of the original \f$ (u, v) \f$ arc will be
  1.2272 +  /// \f$ u_{out} \f$.  The adaptor will add for each node in the 
  1.2273 +  /// original digraph an additional arc which will connect 
  1.2274 +  /// \f$ (u_{in}, u_{out}) \f$.
  1.2275 +  ///
  1.2276 +  /// The aim of this class is to run algorithm with node costs if the 
  1.2277 +  /// algorithm can use directly just arc costs. In this case we should use
  1.2278 +  /// a \c SplitDigraphAdaptor and set the node cost of the digraph to the
  1.2279 +  /// bind arc in the adapted digraph.
  1.2280 +  /// 
  1.2281 +  /// By example a maximum flow algoritm can compute how many arc
  1.2282 +  /// disjoint paths are in the digraph. But we would like to know how
  1.2283 +  /// many node disjoint paths are in the digraph. First we have to
  1.2284 +  /// adapt the digraph with the \c SplitDigraphAdaptor. Then run the flow
  1.2285 +  /// algorithm on the adapted digraph. The bottleneck of the flow will
  1.2286 +  /// be the bind arcs which bounds the flow with the count of the
  1.2287 +  /// node disjoint paths.
  1.2288 +  ///
  1.2289 +  ///\code
  1.2290 +  ///
  1.2291 +  /// typedef SplitDigraphAdaptor<SmartDigraph> SDigraph;
  1.2292 +  ///
  1.2293 +  /// SDigraph sdigraph(digraph);
  1.2294 +  ///
  1.2295 +  /// typedef ConstMap<SDigraph::Arc, int> SCapacity;
  1.2296 +  /// SCapacity scapacity(1);
  1.2297 +  ///
  1.2298 +  /// SDigraph::ArcMap<int> sflow(sdigraph);
  1.2299 +  ///
  1.2300 +  /// Preflow<SDigraph, SCapacity> 
  1.2301 +  ///   spreflow(sdigraph, scapacity, 
  1.2302 +  ///            SDigraph::outNode(source), SDigraph::inNode(target));
  1.2303 +  ///                                            
  1.2304 +  /// spreflow.run();
  1.2305 +  ///
  1.2306 +  ///\endcode
  1.2307 +  ///
  1.2308 +  /// The result of the mamixum flow on the original digraph
  1.2309 +  /// shows the next figure:
  1.2310 +  ///
  1.2311 +  /// \image html arc_disjoint.png
  1.2312 +  /// \image latex arc_disjoint.eps "Arc disjoint paths" width=\textwidth
  1.2313 +  /// 
  1.2314 +  /// And the maximum flow on the adapted digraph:
  1.2315 +  ///
  1.2316 +  /// \image html node_disjoint.png
  1.2317 +  /// \image latex node_disjoint.eps "Node disjoint paths" width=\textwidth
  1.2318 +  ///
  1.2319 +  /// The second solution contains just 3 disjoint paths while the first 4.
  1.2320 +  /// The full code can be found in the \ref disjoint_paths_demo.cc demo file.
  1.2321 +  ///
  1.2322 +  /// This digraph adaptor is fully conform to the 
  1.2323 +  /// \ref concepts::Digraph "Digraph" concept and
  1.2324 +  /// contains some additional member functions and types. The 
  1.2325 +  /// documentation of some member functions may be found just in the
  1.2326 +  /// SplitDigraphAdaptorBase class.
  1.2327 +  ///
  1.2328 +  /// \sa SplitDigraphAdaptorBase
  1.2329 +  template <typename _Digraph>
  1.2330 +  class SplitDigraphAdaptor 
  1.2331 +    : public DigraphAdaptorExtender<SplitDigraphAdaptorBase<_Digraph> > {
  1.2332 +  public:
  1.2333 +    typedef _Digraph Digraph;
  1.2334 +    typedef DigraphAdaptorExtender<SplitDigraphAdaptorBase<Digraph> > Parent;
  1.2335 +
  1.2336 +    typedef typename Parent::Node Node;
  1.2337 +    typedef typename Parent::Arc Arc;
  1.2338 +
  1.2339 +    /// \brief Constructor of the adaptor.
  1.2340 +    ///
  1.2341 +    /// Constructor of the adaptor.
  1.2342 +    SplitDigraphAdaptor(Digraph& g) {
  1.2343 +      Parent::setDigraph(g);
  1.2344 +    }
  1.2345 +
  1.2346 +    /// \brief NodeMap combined from two original NodeMap
  1.2347 +    ///
  1.2348 +    /// This class adapt two of the original digraph NodeMap to
  1.2349 +    /// get a node map on the adapted digraph.
  1.2350 +    template <typename InNodeMap, typename OutNodeMap>
  1.2351 +    class CombinedNodeMap {
  1.2352 +    public:
  1.2353 +
  1.2354 +      typedef Node Key;
  1.2355 +      typedef typename InNodeMap::Value Value;
  1.2356 +
  1.2357 +      /// \brief Constructor
  1.2358 +      ///
  1.2359 +      /// Constructor.
  1.2360 +      CombinedNodeMap(InNodeMap& in_map, OutNodeMap& out_map) 
  1.2361 +	: _in_map(in_map), _out_map(out_map) {}
  1.2362 +
  1.2363 +      /// \brief The subscript operator.
  1.2364 +      ///
  1.2365 +      /// The subscript operator.
  1.2366 +      Value& operator[](const Key& key) {
  1.2367 +	if (Parent::inNode(key)) {
  1.2368 +	  return _in_map[key];
  1.2369 +	} else {
  1.2370 +	  return _out_map[key];
  1.2371 +	}
  1.2372 +      }
  1.2373 +
  1.2374 +      /// \brief The const subscript operator.
  1.2375 +      ///
  1.2376 +      /// The const subscript operator.
  1.2377 +      Value operator[](const Key& key) const {
  1.2378 +	if (Parent::inNode(key)) {
  1.2379 +	  return _in_map[key];
  1.2380 +	} else {
  1.2381 +	  return _out_map[key];
  1.2382 +	}
  1.2383 +      }
  1.2384 +
  1.2385 +      /// \brief The setter function of the map.
  1.2386 +      /// 
  1.2387 +      /// The setter function of the map.
  1.2388 +      void set(const Key& key, const Value& value) {
  1.2389 +	if (Parent::inNode(key)) {
  1.2390 +	  _in_map.set(key, value);
  1.2391 +	} else {
  1.2392 +	  _out_map.set(key, value);
  1.2393 +	}
  1.2394 +      }
  1.2395 +      
  1.2396 +    private:
  1.2397 +      
  1.2398 +      InNodeMap& _in_map;
  1.2399 +      OutNodeMap& _out_map;
  1.2400 +      
  1.2401 +    };
  1.2402 +
  1.2403 +
  1.2404 +    /// \brief Just gives back a combined node map.
  1.2405 +    /// 
  1.2406 +    /// Just gives back a combined node map.
  1.2407 +    template <typename InNodeMap, typename OutNodeMap>
  1.2408 +    static CombinedNodeMap<InNodeMap, OutNodeMap> 
  1.2409 +    combinedNodeMap(InNodeMap& in_map, OutNodeMap& out_map) {
  1.2410 +      return CombinedNodeMap<InNodeMap, OutNodeMap>(in_map, out_map);
  1.2411 +    }
  1.2412 +
  1.2413 +    template <typename InNodeMap, typename OutNodeMap>
  1.2414 +    static CombinedNodeMap<const InNodeMap, OutNodeMap> 
  1.2415 +    combinedNodeMap(const InNodeMap& in_map, OutNodeMap& out_map) {
  1.2416 +      return CombinedNodeMap<const InNodeMap, OutNodeMap>(in_map, out_map);
  1.2417 +    }
  1.2418 +
  1.2419 +    template <typename InNodeMap, typename OutNodeMap>
  1.2420 +    static CombinedNodeMap<InNodeMap, const OutNodeMap> 
  1.2421 +    combinedNodeMap(InNodeMap& in_map, const OutNodeMap& out_map) {
  1.2422 +      return CombinedNodeMap<InNodeMap, const OutNodeMap>(in_map, out_map);
  1.2423 +    }
  1.2424 +
  1.2425 +    template <typename InNodeMap, typename OutNodeMap>
  1.2426 +    static CombinedNodeMap<const InNodeMap, const OutNodeMap> 
  1.2427 +    combinedNodeMap(const InNodeMap& in_map, const OutNodeMap& out_map) {
  1.2428 +      return CombinedNodeMap<const InNodeMap, 
  1.2429 +        const OutNodeMap>(in_map, out_map);
  1.2430 +    }
  1.2431 +
  1.2432 +    /// \brief ArcMap combined from an original ArcMap and NodeMap
  1.2433 +    ///
  1.2434 +    /// This class adapt an original digraph ArcMap and NodeMap to
  1.2435 +    /// get an arc map on the adapted digraph.
  1.2436 +    template <typename DigraphArcMap, typename DigraphNodeMap>
  1.2437 +    class CombinedArcMap {
  1.2438 +    public:
  1.2439 +      
  1.2440 +      typedef Arc Key;
  1.2441 +      typedef typename DigraphArcMap::Value Value;
  1.2442 +      
  1.2443 +      /// \brief Constructor
  1.2444 +      ///
  1.2445 +      /// Constructor.
  1.2446 +      CombinedArcMap(DigraphArcMap& arc_map, DigraphNodeMap& node_map) 
  1.2447 +	: _arc_map(arc_map), _node_map(node_map) {}
  1.2448 +
  1.2449 +      /// \brief The subscript operator.
  1.2450 +      ///
  1.2451 +      /// The subscript operator.
  1.2452 +      void set(const Arc& arc, const Value& val) {
  1.2453 +	if (Parent::origArc(arc)) {
  1.2454 +	  _arc_map.set(arc, val);
  1.2455 +	} else {
  1.2456 +	  _node_map.set(arc, val);
  1.2457 +	}
  1.2458 +      }
  1.2459 +
  1.2460 +      /// \brief The const subscript operator.
  1.2461 +      ///
  1.2462 +      /// The const subscript operator.
  1.2463 +      Value operator[](const Key& arc) const {
  1.2464 +	if (Parent::origArc(arc)) {
  1.2465 +	  return _arc_map[arc];
  1.2466 +	} else {
  1.2467 +	  return _node_map[arc];
  1.2468 +	}
  1.2469 +      }      
  1.2470 +
  1.2471 +      /// \brief The const subscript operator.
  1.2472 +      ///
  1.2473 +      /// The const subscript operator.
  1.2474 +      Value& operator[](const Key& arc) {
  1.2475 +	if (Parent::origArc(arc)) {
  1.2476 +	  return _arc_map[arc];
  1.2477 +	} else {
  1.2478 +	  return _node_map[arc];
  1.2479 +	}
  1.2480 +      }      
  1.2481 +      
  1.2482 +    private:
  1.2483 +      DigraphArcMap& _arc_map;
  1.2484 +      DigraphNodeMap& _node_map;
  1.2485 +    };
  1.2486 +                    
  1.2487 +    /// \brief Just gives back a combined arc map.
  1.2488 +    /// 
  1.2489 +    /// Just gives back a combined arc map.
  1.2490 +    template <typename DigraphArcMap, typename DigraphNodeMap>
  1.2491 +    static CombinedArcMap<DigraphArcMap, DigraphNodeMap> 
  1.2492 +    combinedArcMap(DigraphArcMap& arc_map, DigraphNodeMap& node_map) {
  1.2493 +      return CombinedArcMap<DigraphArcMap, DigraphNodeMap>(arc_map, node_map);
  1.2494 +    }
  1.2495 +
  1.2496 +    template <typename DigraphArcMap, typename DigraphNodeMap>
  1.2497 +    static CombinedArcMap<const DigraphArcMap, DigraphNodeMap> 
  1.2498 +    combinedArcMap(const DigraphArcMap& arc_map, DigraphNodeMap& node_map) {
  1.2499 +      return CombinedArcMap<const DigraphArcMap, 
  1.2500 +        DigraphNodeMap>(arc_map, node_map);
  1.2501 +    }
  1.2502 +
  1.2503 +    template <typename DigraphArcMap, typename DigraphNodeMap>
  1.2504 +    static CombinedArcMap<DigraphArcMap, const DigraphNodeMap> 
  1.2505 +    combinedArcMap(DigraphArcMap& arc_map, const DigraphNodeMap& node_map) {
  1.2506 +      return CombinedArcMap<DigraphArcMap, 
  1.2507 +        const DigraphNodeMap>(arc_map, node_map);
  1.2508 +    }
  1.2509 +
  1.2510 +    template <typename DigraphArcMap, typename DigraphNodeMap>
  1.2511 +    static CombinedArcMap<const DigraphArcMap, const DigraphNodeMap> 
  1.2512 +    combinedArcMap(const DigraphArcMap& arc_map, 
  1.2513 +                    const DigraphNodeMap& node_map) {
  1.2514 +      return CombinedArcMap<const DigraphArcMap, 
  1.2515 +        const DigraphNodeMap>(arc_map, node_map);
  1.2516 +    }
  1.2517 +
  1.2518 +  };
  1.2519 +
  1.2520 +  /// \brief Just gives back a split digraph adaptor
  1.2521 +  ///
  1.2522 +  /// Just gives back a split digraph adaptor
  1.2523 +  template<typename Digraph>
  1.2524 +  SplitDigraphAdaptor<Digraph>
  1.2525 +  splitDigraphAdaptor(const Digraph& digraph) {
  1.2526 +    return SplitDigraphAdaptor<Digraph>(digraph);
  1.2527 +  }
  1.2528 +
  1.2529 +
  1.2530 +} //namespace lemon
  1.2531 +
  1.2532 +#endif //LEMON_DIGRAPH_ADAPTOR_H
  1.2533 +