Hmmm...
2 * lemon/dfs.h - Part of LEMON, a generic C++ optimization library
4 * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
5 * (Egervary Research Group on Combinatorial Optimization, EGRES).
7 * Permission to use, modify and distribute this software is granted
8 * provided that this copyright notice appears in all copies. For
9 * precise terms see the accompanying LICENSE file.
11 * This software is provided "AS IS" with no warranty of any kind,
12 * express or implied, and with no claim as to its suitability for any
22 ///\brief Dfs algorithm.
24 #include <lemon/list_graph.h>
25 #include <lemon/graph_utils.h>
26 #include <lemon/invalid.h>
27 #include <lemon/error.h>
28 #include <lemon/maps.h>
34 ///Default traits class of Dfs class.
36 ///Default traits class of Dfs class.
37 ///\param GR Graph type.
39 struct DfsDefaultTraits
41 ///The graph type the algorithm runs on.
43 ///\brief The type of the map that stores the last
44 ///edges of the %DFS paths.
46 ///The type of the map that stores the last
47 ///edges of the %DFS paths.
48 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
50 typedef typename Graph::template NodeMap<typename GR::Edge> PredMap;
51 ///Instantiates a PredMap.
53 ///This function instantiates a \ref PredMap.
54 ///\param G is the graph, to which we would like to define the PredMap.
55 ///\todo The graph alone may be insufficient to initialize
56 static PredMap *createPredMap(const GR &G)
58 return new PredMap(G);
60 // ///\brief The type of the map that stores the last but one
61 // ///nodes of the %DFS paths.
63 // ///The type of the map that stores the last but one
64 // ///nodes of the %DFS paths.
65 // ///It must meet the \ref concept::WriteMap "WriteMap" concept.
67 // typedef NullMap<typename Graph::Node,typename Graph::Node> PredNodeMap;
68 // ///Instantiates a PredNodeMap.
70 // ///This function instantiates a \ref PredNodeMap.
71 // ///\param G is the graph, to which
72 // ///we would like to define the \ref PredNodeMap
73 // static PredNodeMap *createPredNodeMap(const GR &G)
75 // return new PredNodeMap();
78 ///The type of the map that indicates which nodes are processed.
80 ///The type of the map that indicates which nodes are processed.
81 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
82 ///\todo named parameter to set this type, function to read and write.
83 typedef NullMap<typename Graph::Node,bool> ProcessedMap;
84 ///Instantiates a ProcessedMap.
86 ///This function instantiates a \ref ProcessedMap.
87 ///\param G is the graph, to which
88 ///we would like to define the \ref ProcessedMap
89 static ProcessedMap *createProcessedMap(const GR &)
91 return new ProcessedMap();
93 ///The type of the map that indicates which nodes are reached.
95 ///The type of the map that indicates which nodes are reached.
96 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
97 ///\todo named parameter to set this type, function to read and write.
98 typedef typename Graph::template NodeMap<bool> ReachedMap;
99 ///Instantiates a ReachedMap.
101 ///This function instantiates a \ref ReachedMap.
102 ///\param G is the graph, to which
103 ///we would like to define the \ref ReachedMap.
104 static ReachedMap *createReachedMap(const GR &G)
106 return new ReachedMap(G);
108 ///The type of the map that stores the dists of the nodes.
110 ///The type of the map that stores the dists of the nodes.
111 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
113 typedef typename Graph::template NodeMap<int> DistMap;
114 ///Instantiates a DistMap.
116 ///This function instantiates a \ref DistMap.
117 ///\param G is the graph, to which we would like to define the \ref DistMap
118 static DistMap *createDistMap(const GR &G)
120 return new DistMap(G);
124 ///%DFS algorithm class.
127 ///This class provides an efficient implementation of the %DFS algorithm.
129 ///\param GR The graph type the algorithm runs on. The default value is
130 ///\ref ListGraph. The value of GR is not used directly by Dfs, it
131 ///is only passed to \ref DfsDefaultTraits.
132 ///\param TR Traits class to set various data types used by the algorithm.
133 ///The default traits class is
134 ///\ref DfsDefaultTraits "DfsDefaultTraits<GR>".
135 ///See \ref DfsDefaultTraits for the documentation of
136 ///a Dfs traits class.
138 ///\author Jacint Szabo and Alpar Juttner
139 ///\todo A compare object would be nice.
142 template <typename GR,
145 template <typename GR=ListGraph,
146 typename TR=DfsDefaultTraits<GR> >
151 * \brief \ref Exception for uninitialized parameters.
153 * This error represents problems in the initialization
154 * of the parameters of the algorithms.
156 class UninitializedParameter : public lemon::UninitializedParameter {
158 virtual const char* exceptionName() const {
159 return "lemon::Dfs::UninitializedParameter";
164 ///The type of the underlying graph.
165 typedef typename TR::Graph Graph;
167 typedef typename Graph::Node Node;
169 typedef typename Graph::NodeIt NodeIt;
171 typedef typename Graph::Edge Edge;
173 typedef typename Graph::OutEdgeIt OutEdgeIt;
175 ///\brief The type of the map that stores the last
176 ///edges of the %DFS paths.
177 typedef typename TR::PredMap PredMap;
178 // ///\brief The type of the map that stores the last but one
179 // ///nodes of the %DFS paths.
180 // typedef typename TR::PredNodeMap PredNodeMap;
181 ///The type of the map indicating which nodes are reached.
182 typedef typename TR::ReachedMap ReachedMap;
183 ///The type of the map indicating which nodes are processed.
184 typedef typename TR::ProcessedMap ProcessedMap;
185 ///The type of the map that stores the dists of the nodes.
186 typedef typename TR::DistMap DistMap;
188 /// Pointer to the underlying graph.
190 ///Pointer to the map of predecessors edges.
192 ///Indicates if \ref _pred is locally allocated (\c true) or not.
194 // ///Pointer to the map of predecessors nodes.
195 // PredNodeMap *_predNode;
196 // ///Indicates if \ref _predNode is locally allocated (\c true) or not.
197 // bool local_predNode;
198 ///Pointer to the map of distances.
200 ///Indicates if \ref _dist is locally allocated (\c true) or not.
202 ///Pointer to the map of reached status of the nodes.
203 ReachedMap *_reached;
204 ///Indicates if \ref _reached is locally allocated (\c true) or not.
206 ///Pointer to the map of processed status of the nodes.
207 ProcessedMap *_processed;
208 ///Indicates if \ref _processed is locally allocated (\c true) or not.
209 bool local_processed;
211 std::vector<typename Graph::OutEdgeIt> _stack;
213 // ///The source node of the last execution.
216 ///Creates the maps if necessary.
218 ///\todo Error if \c G are \c NULL.
219 ///\todo Better memory allocation (instead of new).
224 _pred = Traits::createPredMap(*G);
227 // local_predNode = true;
228 // _predNode = Traits::createPredNodeMap(*G);
232 _dist = Traits::createDistMap(*G);
235 local_reached = true;
236 _reached = Traits::createReachedMap(*G);
239 local_processed = true;
240 _processed = Traits::createProcessedMap(*G);
246 ///\name Named template parameters
251 struct DefPredMapTraits : public Traits {
253 static PredMap *createPredMap(const Graph &G)
255 throw UninitializedParameter();
258 ///\ref named-templ-param "Named parameter" for setting PredMap type
260 ///\ref named-templ-param "Named parameter" for setting PredMap type
263 class DefPredMap : public Dfs< Graph,
264 DefPredMapTraits<T> > { };
266 // template <class T>
267 // struct DefPredNodeMapTraits : public Traits {
268 // typedef T PredNodeMap;
269 // static PredNodeMap *createPredNodeMap(const Graph &G)
271 // throw UninitializedParameter();
274 // ///\ref named-templ-param "Named parameter" for setting PredNodeMap type
276 // ///\ref named-templ-param "Named parameter" for setting PredNodeMap type
278 // template <class T>
279 // class DefPredNodeMap : public Dfs< Graph,
281 // DefPredNodeMapTraits<T> > { };
284 struct DefDistMapTraits : public Traits {
286 static DistMap *createDistMap(const Graph &G)
288 throw UninitializedParameter();
291 ///\ref named-templ-param "Named parameter" for setting DistMap type
293 ///\ref named-templ-param "Named parameter" for setting DistMap type
296 class DefDistMap : public Dfs< Graph,
297 DefDistMapTraits<T> > { };
300 struct DefReachedMapTraits : public Traits {
301 typedef T ReachedMap;
302 static ReachedMap *createReachedMap(const Graph &G)
304 throw UninitializedParameter();
307 ///\ref named-templ-param "Named parameter" for setting ReachedMap type
309 ///\ref named-templ-param "Named parameter" for setting ReachedMap type
312 class DefReachedMap : public Dfs< Graph,
313 DefReachedMapTraits<T> > { };
315 struct DefGraphReachedMapTraits : public Traits {
316 typedef typename Graph::template NodeMap<bool> ReachedMap;
317 static ReachedMap *createReachedMap(const Graph &G)
319 return new ReachedMap(G);
323 struct DefProcessedMapTraits : public Traits {
324 typedef T ProcessedMap;
325 static ProcessedMap *createProcessedMap(const Graph &G)
327 throw UninitializedParameter();
330 ///\ref named-templ-param "Named parameter" for setting ProcessedMap type
332 ///\ref named-templ-param "Named parameter" for setting ProcessedMap type
335 class DefProcessedMap : public Dfs< Graph,
336 DefProcessedMapTraits<T> > { };
338 struct DefGraphProcessedMapTraits : public Traits {
339 typedef typename Graph::template NodeMap<bool> ProcessedMap;
340 static ProcessedMap *createProcessedMap(const Graph &G)
342 return new ProcessedMap(G);
345 ///\brief \ref named-templ-param "Named parameter"
346 ///for setting the ProcessedMap type to be Graph::NodeMap<bool>.
348 ///\ref named-templ-param "Named parameter"
349 ///for setting the ProcessedMap type to be Graph::NodeMap<bool>.
350 ///If you don't set it explicitely, it will be automatically allocated.
352 class DefProcessedMapToBeDefaultMap :
354 DefGraphProcessedMapTraits> { };
362 ///\param _G the graph the algorithm will run on.
364 Dfs(const Graph& _G) :
366 _pred(NULL), local_pred(false),
367 // _predNode(NULL), local_predNode(false),
368 _dist(NULL), local_dist(false),
369 _reached(NULL), local_reached(false),
370 _processed(NULL), local_processed(false)
376 if(local_pred) delete _pred;
377 // if(local_predNode) delete _predNode;
378 if(local_dist) delete _dist;
379 if(local_reached) delete _reached;
380 if(local_processed) delete _processed;
383 ///Sets the map storing the predecessor edges.
385 ///Sets the map storing the predecessor edges.
386 ///If you don't use this function before calling \ref run(),
387 ///it will allocate one. The destuctor deallocates this
388 ///automatically allocated map, of course.
389 ///\return <tt> (*this) </tt>
390 Dfs &predMap(PredMap &m)
400 // ///Sets the map storing the predecessor nodes.
402 // ///Sets the map storing the predecessor nodes.
403 // ///If you don't use this function before calling \ref run(),
404 // ///it will allocate one. The destuctor deallocates this
405 // ///automatically allocated map, of course.
406 // ///\return <tt> (*this) </tt>
407 // Dfs &predNodeMap(PredNodeMap &m)
409 // if(local_predNode) {
411 // local_predNode=false;
417 ///Sets the map storing the distances calculated by the algorithm.
419 ///Sets the map storing the distances calculated by the algorithm.
420 ///If you don't use this function before calling \ref run(),
421 ///it will allocate one. The destuctor deallocates this
422 ///automatically allocated map, of course.
423 ///\return <tt> (*this) </tt>
424 Dfs &distMap(DistMap &m)
434 ///Sets the map indicating if a node is reached.
436 ///Sets the map indicating if a node is reached.
437 ///If you don't use this function before calling \ref run(),
438 ///it will allocate one. The destuctor deallocates this
439 ///automatically allocated map, of course.
440 ///\return <tt> (*this) </tt>
441 Dfs &reachedMap(ReachedMap &m)
451 ///Sets the map indicating if a node is processed.
453 ///Sets the map indicating if a node is processed.
454 ///If you don't use this function before calling \ref run(),
455 ///it will allocate one. The destuctor deallocates this
456 ///automatically allocated map, of course.
457 ///\return <tt> (*this) </tt>
458 Dfs &processedMap(ProcessedMap &m)
460 if(local_processed) {
462 local_processed=false;
469 ///\name Execution control
470 ///The simplest way to execute the algorithm is to use
471 ///one of the member functions called \c run(...).
473 ///If you need more control on the execution,
474 ///first you must call \ref init(), then you can add several source nodes
475 ///with \ref addSource().
476 ///Finally \ref start() will perform the actual path
481 ///Initializes the internal data structures.
483 ///Initializes the internal data structures.
488 _stack.resize(countNodes(*G));
490 for ( NodeIt u(*G) ; u!=INVALID ; ++u ) {
491 _pred->set(u,INVALID);
492 // _predNode->set(u,INVALID);
493 _reached->set(u,false);
494 _processed->set(u,false);
498 ///Adds a new source node.
500 ///Adds a new source node to the set of nodes to be processed.
502 ///\bug dists are wrong (or at least strange) in case of multiple sources.
503 void addSource(Node s)
507 _reached->set(s,true);
508 _pred->set(s,INVALID);
509 // _predNode->set(u,INVALID);
510 _stack[++_stack_head]=OutEdgeIt(*G,s);
511 _dist->set(s,_stack_head);
515 ///Processes the next node.
517 ///Processes the next node.
519 ///\return The processed edge.
521 ///\pre The stack must not be empty!
522 Edge processNextEdge()
525 Edge e=_stack[_stack_head];
526 if(!(*_reached)[m=G->target(e)]) {
528 _reached->set(m,true);
529 // _pred_node->set(m,G->source(e));
531 _stack[_stack_head] = OutEdgeIt(*G, m);
532 _dist->set(m,_stack_head);
536 while(_stack_head>=0 &&
537 (n=G->source(_stack[_stack_head]),
538 ++_stack[_stack_head]==INVALID))
540 _processed->set(n,true);
547 ///\brief Returns \c false if there are nodes
548 ///to be processed in the queue
550 ///Returns \c false if there are nodes
551 ///to be processed in the queue
552 bool emptyQueue() { return _stack_head<0; }
553 ///Returns the number of the nodes to be processed.
555 ///Returns the number of the nodes to be processed in the queue.
557 int queueSize() { return _stack_head+1; }
559 ///Executes the algorithm.
561 ///Executes the algorithm.
563 ///\pre init() must be called and at least one node should be added
564 ///with addSource() before using this function.
566 ///This method runs the %DFS algorithm from the root node(s)
569 ///%DFS path to each node. The algorithm computes
571 ///- The distance of each node from the root(s) in the %DFS tree.
575 while ( !emptyQueue() ) processNextEdge();
578 ///Executes the algorithm until \c dest is reached.
580 ///Executes the algorithm until \c dest is reached.
582 ///\pre init() must be called and at least one node should be added
583 ///with addSource() before using this function.
585 ///This method runs the %DFS algorithm from the root node(s)
588 ///%DFS path to \c dest. The algorithm computes
589 ///- The %DFS path to \c dest.
590 ///- The distance of \c dest from the root(s) in the %DFS tree.
592 void start(Node dest)
594 while ( !emptyQueue() && G->target(_stack[_stack_head])!=dest )
598 ///Executes the algorithm until a condition is met.
600 ///Executes the algorithm until a condition is met.
602 ///\pre init() must be called and at least one node should be added
603 ///with addSource() before using this function.
605 ///\param nm must be a bool (or convertible) edge map. The algorithm
606 ///will stop when it reaches an edge \c e with <tt>nm[e]==true</tt>.
608 ///\warning Contrary to \ref Dfs and \ref Dijkstra, \c nm is an edge map,
611 void start(const NM &nm)
613 while ( !emptyQueue() && !nm[_stack[_stack_head]] ) processNextEdge();
616 ///Runs %DFS algorithm from node \c s.
618 ///This method runs the %DFS algorithm from a root node \c s
621 ///%DFS path to each node. The algorithm computes
623 ///- The distance of each node from the root in the %DFS tree.
625 ///\note d.run(s) is just a shortcut of the following code.
637 ///Finds the %DFS path between \c s and \c t.
639 ///Finds the %DFS path between \c s and \c t.
641 ///\return The length of the %DFS s---t path if there exists one,
643 ///\note Apart from the return value, d.run(s) is
644 ///just a shortcut of the following code.
650 int run(Node s,Node t) {
654 return reached(t)?_stack_head+1:0;
659 ///\name Query Functions
660 ///The result of the %DFS algorithm can be obtained using these
662 ///Before the use of these functions,
663 ///either run() or start() must be called.
667 ///Copies the path to \c t on the DFS tree into \c p
669 ///This function copies the path to \c t on the DFS tree into \c p.
670 ///If \c t is a source itself or unreachable, then it does not
672 ///\todo Is this the right way to handle unreachable nodes?
674 ///\return Returns \c true if a path to \c t was actually copied to \c p,
675 ///\c false otherwise.
678 bool getPath(P &p,Node t)
682 typename P::Builder b(p);
683 for(b.setStartNode(t);pred(t)!=INVALID;t=predNode(t))
684 b.pushFront(pred(t));
691 ///The distance of a node from the root(s).
693 ///Returns the distance of a node from the root(s).
694 ///\pre \ref run() must be called before using this function.
695 ///\warning If node \c v is unreachable from the root(s) then the return value
696 ///of this funcion is undefined.
697 int dist(Node v) const { return (*_dist)[v]; }
699 ///Returns the 'previous edge' of the %DFS tree.
701 ///For a node \c v it returns the 'previous edge'
703 ///i.e. it returns the last edge of a %DFS path from the root(s) to \c
704 ///v. It is \ref INVALID
705 ///if \c v is unreachable from the root(s) or \c v is a root. The
706 ///%DFS tree used here is equal to the %DFS tree used in
707 ///\ref predNode(Node v).
708 ///\pre Either \ref run() or \ref start() must be called before using
710 ///\todo predEdge could be a better name.
711 Edge pred(Node v) const { return (*_pred)[v];}
713 ///Returns the 'previous node' of the %DFS tree.
715 ///For a node \c v it returns the 'previous node'
717 ///i.e. it returns the last but one node from a %DFS path from the
719 ///It is INVALID if \c v is unreachable from the root(s) or
720 ///if \c v itself a root.
721 ///The %DFS tree used here is equal to the %DFS
722 ///tree used in \ref pred(Node v).
723 ///\pre Either \ref run() or \ref start() must be called before
724 ///using this function.
725 Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID:
726 G->source((*_pred)[v]); }
728 ///Returns a reference to the NodeMap of distances.
730 ///Returns a reference to the NodeMap of distances.
731 ///\pre Either \ref run() or \ref init() must
732 ///be called before using this function.
733 const DistMap &distMap() const { return *_dist;}
735 ///Returns a reference to the %DFS edge-tree map.
737 ///Returns a reference to the NodeMap of the edges of the
739 ///\pre Either \ref run() or \ref init()
740 ///must be called before using this function.
741 const PredMap &predMap() const { return *_pred;}
743 // ///Returns a reference to the map of nodes of %DFS paths.
745 // ///Returns a reference to the NodeMap of the last but one nodes of the
747 // ///\pre \ref run() must be called before using this function.
748 // const PredNodeMap &predNodeMap() const { return *_predNode;}
750 ///Checks if a node is reachable from the root.
752 ///Returns \c true if \c v is reachable from the root(s).
753 ///\warning The source nodes are inditated as unreachable.
754 ///\pre Either \ref run() or \ref start()
755 ///must be called before using this function.
757 bool reached(Node v) { return (*_reached)[v]; }
762 ///Default traits class of Dfs function.
764 ///Default traits class of Dfs function.
765 ///\param GR Graph type.
767 struct DfsWizardDefaultTraits
769 ///The graph type the algorithm runs on.
771 ///\brief The type of the map that stores the last
772 ///edges of the %DFS paths.
774 ///The type of the map that stores the last
775 ///edges of the %DFS paths.
776 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
778 typedef NullMap<typename Graph::Node,typename GR::Edge> PredMap;
779 ///Instantiates a PredMap.
781 ///This function instantiates a \ref PredMap.
782 ///\param G is the graph, to which we would like to define the PredMap.
783 ///\todo The graph alone may be insufficient to initialize
784 static PredMap *createPredMap(const GR &)
786 return new PredMap();
788 // ///\brief The type of the map that stores the last but one
789 // ///nodes of the %DFS paths.
791 // ///The type of the map that stores the last but one
792 // ///nodes of the %DFS paths.
793 // ///It must meet the \ref concept::WriteMap "WriteMap" concept.
795 // typedef NullMap<typename Graph::Node,typename Graph::Node> PredNodeMap;
796 // ///Instantiates a PredNodeMap.
798 // ///This function instantiates a \ref PredNodeMap.
799 // ///\param G is the graph, to which
800 // ///we would like to define the \ref PredNodeMap
801 // static PredNodeMap *createPredNodeMap(const GR &G)
803 // return new PredNodeMap();
806 ///The type of the map that indicates which nodes are processed.
808 ///The type of the map that indicates which nodes are processed.
809 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
810 ///\todo named parameter to set this type, function to read and write.
811 typedef NullMap<typename Graph::Node,bool> ProcessedMap;
812 ///Instantiates a ProcessedMap.
814 ///This function instantiates a \ref ProcessedMap.
815 ///\param G is the graph, to which
816 ///we would like to define the \ref ProcessedMap
817 static ProcessedMap *createProcessedMap(const GR &)
819 return new ProcessedMap();
821 ///The type of the map that indicates which nodes are reached.
823 ///The type of the map that indicates which nodes are reached.
824 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
825 ///\todo named parameter to set this type, function to read and write.
826 typedef typename Graph::template NodeMap<bool> ReachedMap;
827 ///Instantiates a ReachedMap.
829 ///This function instantiates a \ref ReachedMap.
830 ///\param G is the graph, to which
831 ///we would like to define the \ref ReachedMap.
832 static ReachedMap *createReachedMap(const GR &G)
834 return new ReachedMap(G);
836 ///The type of the map that stores the dists of the nodes.
838 ///The type of the map that stores the dists of the nodes.
839 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
841 typedef NullMap<typename Graph::Node,int> DistMap;
842 ///Instantiates a DistMap.
844 ///This function instantiates a \ref DistMap.
845 ///\param G is the graph, to which we would like to define the \ref DistMap
846 static DistMap *createDistMap(const GR &)
848 return new DistMap();
852 /// Default traits used by \ref DfsWizard
854 /// To make it easier to use Dfs algorithm
855 ///we have created a wizard class.
856 /// This \ref DfsWizard class needs default traits,
857 ///as well as the \ref Dfs class.
858 /// The \ref DfsWizardBase is a class to be the default traits of the
859 /// \ref DfsWizard class.
861 class DfsWizardBase : public DfsWizardDefaultTraits<GR>
864 typedef DfsWizardDefaultTraits<GR> Base;
866 /// Type of the nodes in the graph.
867 typedef typename Base::Graph::Node Node;
869 /// Pointer to the underlying graph.
871 ///Pointer to the map of reached nodes.
873 ///Pointer to the map of processed nodes.
875 ///Pointer to the map of predecessors edges.
877 // ///Pointer to the map of predecessors nodes.
879 ///Pointer to the map of distances.
881 ///Pointer to the source node.
887 /// This constructor does not require parameters, therefore it initiates
888 /// all of the attributes to default values (0, INVALID).
889 DfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0),
891 _dist(0), _source(INVALID) {}
895 /// This constructor requires some parameters,
896 /// listed in the parameters list.
897 /// Others are initiated to 0.
898 /// \param g is the initial value of \ref _g
899 /// \param s is the initial value of \ref _source
900 DfsWizardBase(const GR &g, Node s=INVALID) :
901 _g((void *)&g), _reached(0), _processed(0), _pred(0),
903 _dist(0), _source(s) {}
907 /// A class to make the usage of the Dfs algorithm easier
909 /// This class is created to make it easier to use the Dfs algorithm.
910 /// It uses the functions and features of the plain \ref Dfs,
911 /// but it is much simpler to use it.
913 /// Simplicity means that the way to change the types defined
914 /// in the traits class is based on functions that returns the new class
915 /// and not on templatable built-in classes.
916 /// When using the plain \ref Dfs
917 /// the new class with the modified type comes from
918 /// the original class by using the ::
919 /// operator. In the case of \ref DfsWizard only
920 /// a function have to be called and it will
921 /// return the needed class.
923 /// It does not have own \ref run method. When its \ref run method is called
924 /// it initiates a plain \ref Dfs object, and calls the \ref Dfs::run
927 class DfsWizard : public TR
931 ///The type of the underlying graph.
932 typedef typename TR::Graph Graph;
934 typedef typename Graph::Node Node;
936 typedef typename Graph::NodeIt NodeIt;
938 typedef typename Graph::Edge Edge;
940 typedef typename Graph::OutEdgeIt OutEdgeIt;
942 ///\brief The type of the map that stores
944 typedef typename TR::ReachedMap ReachedMap;
945 ///\brief The type of the map that stores
946 ///the processed nodes
947 typedef typename TR::ProcessedMap ProcessedMap;
948 ///\brief The type of the map that stores the last
949 ///edges of the %DFS paths.
950 typedef typename TR::PredMap PredMap;
951 // ///\brief The type of the map that stores the last but one
952 // ///nodes of the %DFS paths.
953 // typedef typename TR::PredNodeMap PredNodeMap;
954 ///The type of the map that stores the distances of the nodes.
955 typedef typename TR::DistMap DistMap;
959 DfsWizard() : TR() {}
961 /// Constructor that requires parameters.
963 /// Constructor that requires parameters.
964 /// These parameters will be the default values for the traits class.
965 DfsWizard(const Graph &g, Node s=INVALID) :
969 DfsWizard(const TR &b) : TR(b) {}
973 ///Runs Dfs algorithm from a given node.
975 ///Runs Dfs algorithm from a given node.
976 ///The node can be given by the \ref source function.
979 if(Base::_source==INVALID) throw UninitializedParameter();
980 Dfs<Graph,TR> alg(*(Graph*)Base::_g);
981 if(Base::_reached) alg.reachedMap(*(ReachedMap*)Base::_reached);
982 if(Base::_processed) alg.processedMap(*(ProcessedMap*)Base::_processed);
983 if(Base::_pred) alg.predMap(*(PredMap*)Base::_pred);
984 // if(Base::_predNode) alg.predNodeMap(*(PredNodeMap*)Base::_predNode);
985 if(Base::_dist) alg.distMap(*(DistMap*)Base::_dist);
986 alg.run(Base::_source);
989 ///Runs Dfs algorithm from the given node.
991 ///Runs Dfs algorithm from the given node.
992 ///\param s is the given source.
1000 struct DefPredMapBase : public Base {
1002 static PredMap *createPredMap(const Graph &) { return 0; };
1003 DefPredMapBase(const TR &b) : TR(b) {}
1006 ///\brief \ref named-templ-param "Named parameter"
1007 ///function for setting PredMap type
1009 /// \ref named-templ-param "Named parameter"
1010 ///function for setting PredMap type
1013 DfsWizard<DefPredMapBase<T> > predMap(const T &t)
1015 Base::_pred=(void *)&t;
1016 return DfsWizard<DefPredMapBase<T> >(*this);
1021 struct DefReachedMapBase : public Base {
1022 typedef T ReachedMap;
1023 static ReachedMap *createReachedMap(const Graph &) { return 0; };
1024 DefReachedMapBase(const TR &b) : TR(b) {}
1027 ///\brief \ref named-templ-param "Named parameter"
1028 ///function for setting ReachedMap
1030 /// \ref named-templ-param "Named parameter"
1031 ///function for setting ReachedMap
1034 DfsWizard<DefReachedMapBase<T> > reachedMap(const T &t)
1036 Base::_pred=(void *)&t;
1037 return DfsWizard<DefReachedMapBase<T> >(*this);
1042 struct DefProcessedMapBase : public Base {
1043 typedef T ProcessedMap;
1044 static ProcessedMap *createProcessedMap(const Graph &) { return 0; };
1045 DefProcessedMapBase(const TR &b) : TR(b) {}
1048 ///\brief \ref named-templ-param "Named parameter"
1049 ///function for setting ProcessedMap
1051 /// \ref named-templ-param "Named parameter"
1052 ///function for setting ProcessedMap
1055 DfsWizard<DefProcessedMapBase<T> > processedMap(const T &t)
1057 Base::_pred=(void *)&t;
1058 return DfsWizard<DefProcessedMapBase<T> >(*this);
1062 // template<class T>
1063 // struct DefPredNodeMapBase : public Base {
1064 // typedef T PredNodeMap;
1065 // static PredNodeMap *createPredNodeMap(const Graph &G) { return 0; };
1066 // DefPredNodeMapBase(const TR &b) : TR(b) {}
1069 // ///\brief \ref named-templ-param "Named parameter"
1070 // ///function for setting PredNodeMap type
1072 // /// \ref named-templ-param "Named parameter"
1073 // ///function for setting PredNodeMap type
1075 // template<class T>
1076 // DfsWizard<DefPredNodeMapBase<T> > predNodeMap(const T &t)
1078 // Base::_predNode=(void *)&t;
1079 // return DfsWizard<DefPredNodeMapBase<T> >(*this);
1083 struct DefDistMapBase : public Base {
1085 static DistMap *createDistMap(const Graph &) { return 0; };
1086 DefDistMapBase(const TR &b) : TR(b) {}
1089 ///\brief \ref named-templ-param "Named parameter"
1090 ///function for setting DistMap type
1092 /// \ref named-templ-param "Named parameter"
1093 ///function for setting DistMap type
1096 DfsWizard<DefDistMapBase<T> > distMap(const T &t)
1098 Base::_dist=(void *)&t;
1099 return DfsWizard<DefDistMapBase<T> >(*this);
1102 /// Sets the source node, from which the Dfs algorithm runs.
1104 /// Sets the source node, from which the Dfs algorithm runs.
1105 /// \param s is the source node.
1106 DfsWizard<TR> &source(Node s)
1114 ///Function type interface for Dfs algorithm.
1116 /// \ingroup flowalgs
1117 ///Function type interface for Dfs algorithm.
1119 ///This function also has several
1120 ///\ref named-templ-func-param "named parameters",
1121 ///they are declared as the members of class \ref DfsWizard.
1123 ///example shows how to use these parameters.
1125 /// dfs(g,source).predMap(preds).run();
1127 ///\warning Don't forget to put the \ref DfsWizard::run() "run()"
1128 ///to the end of the parameter list.
1132 DfsWizard<DfsWizardBase<GR> >
1133 dfs(const GR &g,typename GR::Node s=INVALID)
1135 return DfsWizard<DfsWizardBase<GR> >(g,s);
1138 } //END OF NAMESPACE LEMON