Result of KruskalGUIAlgo is refreshed if displayed, but no more setin a forced way.
2 * lemon/bfs.h - Part of LEMON, a generic C++ optimization library
4 * Copyright (C) 2006 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 Bfs 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 Bfs class.
36 ///Default traits class of Bfs class.
37 ///\param GR Graph type.
39 struct BfsDefaultTraits
41 ///The graph type the algorithm runs on.
43 ///\brief The type of the map that stores the last
44 ///edges of the shortest paths.
46 ///The type of the map that stores the last
47 ///edges of the shortest 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 ///The type of the map that indicates which nodes are processed.
62 ///The type of the map that indicates which nodes are processed.
63 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
64 ///\todo named parameter to set this type, function to read and write.
65 typedef NullMap<typename Graph::Node,bool> ProcessedMap;
66 ///Instantiates a ProcessedMap.
68 ///This function instantiates a \ref ProcessedMap.
69 ///\param g is the graph, to which
70 ///we would like to define the \ref ProcessedMap
72 static ProcessedMap *createProcessedMap(const GR &g)
74 static ProcessedMap *createProcessedMap(const GR &)
77 return new ProcessedMap();
79 ///The type of the map that indicates which nodes are reached.
81 ///The type of the map that indicates which nodes are reached.
82 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
83 ///\todo named parameter to set this type, function to read and write.
84 typedef typename Graph::template NodeMap<bool> ReachedMap;
85 ///Instantiates a ReachedMap.
87 ///This function instantiates a \ref ReachedMap.
88 ///\param G is the graph, to which
89 ///we would like to define the \ref ReachedMap.
90 static ReachedMap *createReachedMap(const GR &G)
92 return new ReachedMap(G);
94 ///The type of the map that stores the dists of the nodes.
96 ///The type of the map that stores the dists of the nodes.
97 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
99 typedef typename Graph::template NodeMap<int> DistMap;
100 ///Instantiates a DistMap.
102 ///This function instantiates a \ref DistMap.
103 ///\param G is the graph, to which we would like to define the \ref DistMap
104 static DistMap *createDistMap(const GR &G)
106 return new DistMap(G);
110 ///%BFS algorithm class.
113 ///This class provides an efficient implementation of the %BFS algorithm.
115 ///\param GR The graph type the algorithm runs on. The default value is
116 ///\ref ListGraph. The value of GR is not used directly by Bfs, it
117 ///is only passed to \ref BfsDefaultTraits.
118 ///\param TR Traits class to set various data types used by the algorithm.
119 ///The default traits class is
120 ///\ref BfsDefaultTraits "BfsDefaultTraits<GR>".
121 ///See \ref BfsDefaultTraits for the documentation of
122 ///a Bfs traits class.
124 ///\author Alpar Juttner
127 template <typename GR,
130 template <typename GR=ListGraph,
131 typename TR=BfsDefaultTraits<GR> >
136 * \brief \ref Exception for uninitialized parameters.
138 * This error represents problems in the initialization
139 * of the parameters of the algorithms.
141 class UninitializedParameter : public lemon::UninitializedParameter {
143 virtual const char* exceptionName() const {
144 return "lemon::Bfs::UninitializedParameter";
149 ///The type of the underlying graph.
150 typedef typename TR::Graph Graph;
152 typedef typename Graph::Node Node;
154 typedef typename Graph::NodeIt NodeIt;
156 typedef typename Graph::Edge Edge;
158 typedef typename Graph::OutEdgeIt OutEdgeIt;
160 ///\brief The type of the map that stores the last
161 ///edges of the shortest paths.
162 typedef typename TR::PredMap PredMap;
163 ///The type of the map indicating which nodes are reached.
164 typedef typename TR::ReachedMap ReachedMap;
165 ///The type of the map indicating which nodes are processed.
166 typedef typename TR::ProcessedMap ProcessedMap;
167 ///The type of the map that stores the dists of the nodes.
168 typedef typename TR::DistMap DistMap;
170 /// Pointer to the underlying graph.
172 ///Pointer to the map of predecessors edges.
174 ///Indicates if \ref _pred is locally allocated (\c true) or not.
176 ///Pointer to the map of distances.
178 ///Indicates if \ref _dist is locally allocated (\c true) or not.
180 ///Pointer to the map of reached status of the nodes.
181 ReachedMap *_reached;
182 ///Indicates if \ref _reached is locally allocated (\c true) or not.
184 ///Pointer to the map of processed status of the nodes.
185 ProcessedMap *_processed;
186 ///Indicates if \ref _processed is locally allocated (\c true) or not.
187 bool local_processed;
189 std::vector<typename Graph::Node> _queue;
190 int _queue_head,_queue_tail,_queue_next_dist;
193 ///Creates the maps if necessary.
195 ///\todo Better memory allocation (instead of new).
200 _pred = Traits::createPredMap(*G);
204 _dist = Traits::createDistMap(*G);
207 local_reached = true;
208 _reached = Traits::createReachedMap(*G);
211 local_processed = true;
212 _processed = Traits::createProcessedMap(*G);
224 ///\name Named template parameters
229 struct DefPredMapTraits : public Traits {
231 static PredMap *createPredMap(const Graph &)
233 throw UninitializedParameter();
236 ///\ref named-templ-param "Named parameter" for setting PredMap type
238 ///\ref named-templ-param "Named parameter" for setting PredMap type
241 struct DefPredMap : public Bfs< Graph, DefPredMapTraits<T> > {
242 typedef Bfs< Graph, DefPredMapTraits<T> > Create;
246 struct DefDistMapTraits : public Traits {
248 static DistMap *createDistMap(const Graph &)
250 throw UninitializedParameter();
253 ///\ref named-templ-param "Named parameter" for setting DistMap type
255 ///\ref named-templ-param "Named parameter" for setting DistMap type
258 struct DefDistMap : public Bfs< Graph, DefDistMapTraits<T> > {
259 typedef Bfs< Graph, DefDistMapTraits<T> > Create;
263 struct DefReachedMapTraits : public Traits {
264 typedef T ReachedMap;
265 static ReachedMap *createReachedMap(const Graph &)
267 throw UninitializedParameter();
270 ///\ref named-templ-param "Named parameter" for setting ReachedMap type
272 ///\ref named-templ-param "Named parameter" for setting ReachedMap type
275 struct DefReachedMap : public Bfs< Graph, DefReachedMapTraits<T> > {
276 typedef Bfs< Graph, DefReachedMapTraits<T> > Create;
280 struct DefProcessedMapTraits : public Traits {
281 typedef T ProcessedMap;
282 static ProcessedMap *createProcessedMap(const Graph &G)
284 throw UninitializedParameter();
287 ///\ref named-templ-param "Named parameter" for setting ProcessedMap type
289 ///\ref named-templ-param "Named parameter" for setting ProcessedMap type
292 struct DefProcessedMap : public Bfs< Graph, DefProcessedMapTraits<T> > {
293 typedef Bfs< Graph, DefProcessedMapTraits<T> > Create;
296 struct DefGraphProcessedMapTraits : public Traits {
297 typedef typename Graph::template NodeMap<bool> ProcessedMap;
298 static ProcessedMap *createProcessedMap(const Graph &G)
300 return new ProcessedMap(G);
303 ///\brief \ref named-templ-param "Named parameter"
304 ///for setting the ProcessedMap type to be Graph::NodeMap<bool>.
306 ///\ref named-templ-param "Named parameter"
307 ///for setting the ProcessedMap type to be Graph::NodeMap<bool>.
308 ///If you don't set it explicitly, it will be automatically allocated.
310 struct DefProcessedMapToBeDefaultMap :
311 public Bfs< Graph, DefGraphProcessedMapTraits> {
312 typedef Bfs< Graph, DefGraphProcessedMapTraits> Create;
321 ///\param _G the graph the algorithm will run on.
323 Bfs(const Graph& _G) :
325 _pred(NULL), local_pred(false),
326 _dist(NULL), local_dist(false),
327 _reached(NULL), local_reached(false),
328 _processed(NULL), local_processed(false)
334 if(local_pred) delete _pred;
335 if(local_dist) delete _dist;
336 if(local_reached) delete _reached;
337 if(local_processed) delete _processed;
340 ///Sets the map storing the predecessor edges.
342 ///Sets the map storing the predecessor edges.
343 ///If you don't use this function before calling \ref run(),
344 ///it will allocate one. The destructor deallocates this
345 ///automatically allocated map, of course.
346 ///\return <tt> (*this) </tt>
347 Bfs &predMap(PredMap &m)
357 ///Sets the map indicating the reached nodes.
359 ///Sets the map indicating the reached nodes.
360 ///If you don't use this function before calling \ref run(),
361 ///it will allocate one. The destructor deallocates this
362 ///automatically allocated map, of course.
363 ///\return <tt> (*this) </tt>
364 Bfs &reachedMap(ReachedMap &m)
374 ///Sets the map indicating the processed nodes.
376 ///Sets the map indicating the processed nodes.
377 ///If you don't use this function before calling \ref run(),
378 ///it will allocate one. The destructor deallocates this
379 ///automatically allocated map, of course.
380 ///\return <tt> (*this) </tt>
381 Bfs &processedMap(ProcessedMap &m)
383 if(local_processed) {
385 local_processed=false;
391 ///Sets the map storing the distances calculated by the algorithm.
393 ///Sets the map storing the distances calculated by the algorithm.
394 ///If you don't use this function before calling \ref run(),
395 ///it will allocate one. The destructor deallocates this
396 ///automatically allocated map, of course.
397 ///\return <tt> (*this) </tt>
398 Bfs &distMap(DistMap &m)
409 ///\name Execution control
410 ///The simplest way to execute the algorithm is to use
411 ///one of the member functions called \c run(...).
413 ///If you need more control on the execution,
414 ///first you must call \ref init(), then you can add several source nodes
415 ///with \ref addSource().
416 ///Finally \ref start() will perform the actual path
421 ///Initializes the internal data structures.
423 ///Initializes the internal data structures.
428 _queue.resize(countNodes(*G));
429 _queue_head=_queue_tail=0;
431 for ( NodeIt u(*G) ; u!=INVALID ; ++u ) {
432 _pred->set(u,INVALID);
433 _reached->set(u,false);
434 _processed->set(u,false);
438 ///Adds a new source node.
440 ///Adds a new source node to the set of nodes to be processed.
442 void addSource(Node s)
446 _reached->set(s,true);
447 _pred->set(s,INVALID);
449 _queue[_queue_head++]=s;
450 _queue_next_dist=_queue_head;
454 ///Processes the next node.
456 ///Processes the next node.
458 ///\return The processed node.
460 ///\warning The queue must not be empty!
461 Node processNextNode()
463 if(_queue_tail==_queue_next_dist) {
465 _queue_next_dist=_queue_head;
467 Node n=_queue[_queue_tail++];
468 _processed->set(n,true);
470 for(OutEdgeIt e(*G,n);e!=INVALID;++e)
471 if(!(*_reached)[m=G->target(e)]) {
472 _queue[_queue_head++]=m;
473 _reached->set(m,true);
475 _dist->set(m,_curr_dist);
480 ///Next node to be processed.
482 ///Next node to be processed.
484 ///\return The next node to be processed or INVALID if the queue is
488 return _queue_tail<_queue_head?_queue[_queue_tail]:INVALID;
491 ///\brief Returns \c false if there are nodes
492 ///to be processed in the queue
494 ///Returns \c false if there are nodes
495 ///to be processed in the queue
496 bool emptyQueue() { return _queue_tail==_queue_head; }
497 ///Returns the number of the nodes to be processed.
499 ///Returns the number of the nodes to be processed in the queue.
501 int queueSize() { return _queue_head-_queue_tail; }
503 ///Executes the algorithm.
505 ///Executes the algorithm.
507 ///\pre init() must be called and at least one node should be added
508 ///with addSource() before using this function.
510 ///This method runs the %BFS algorithm from the root node(s)
513 ///shortest path to each node. The algorithm computes
514 ///- The shortest path tree.
515 ///- The distance of each node from the root(s).
519 while ( !emptyQueue() ) processNextNode();
522 ///Executes the algorithm until \c dest is reached.
524 ///Executes the algorithm until \c dest is reached.
526 ///\pre init() must be called and at least one node should be added
527 ///with addSource() before using this function.
529 ///This method runs the %BFS algorithm from the root node(s)
532 ///shortest path to \c dest. The algorithm computes
533 ///- The shortest path to \c dest.
534 ///- The distance of \c dest from the root(s).
536 void start(Node dest)
538 while ( !emptyQueue() && _queue[_queue_tail]!=dest ) processNextNode();
541 ///Executes the algorithm until a condition is met.
543 ///Executes the algorithm until a condition is met.
545 ///\pre init() must be called and at least one node should be added
546 ///with addSource() before using this function.
548 ///\param nm must be a bool (or convertible) node map. The algorithm
549 ///will stop when it reaches a node \c v with <tt>nm[v]==true</tt>.
551 void start(const NM &nm)
553 while ( !emptyQueue() && !nm[_queue[_queue_tail]] ) processNextNode();
556 ///Runs %BFS algorithm from node \c s.
558 ///This method runs the %BFS algorithm from a root node \c s
561 ///shortest path to each node. The algorithm computes
562 ///- The shortest path tree.
563 ///- The distance of each node from the root.
565 ///\note d.run(s) is just a shortcut of the following code.
577 ///Finds the shortest path between \c s and \c t.
579 ///Finds the shortest path between \c s and \c t.
581 ///\return The length of the shortest s---t path if there exists one,
583 ///\note Apart from the return value, d.run(s) is
584 ///just a shortcut of the following code.
590 int run(Node s,Node t) {
594 return reached(t)?_curr_dist-1+(_queue_tail==_queue_next_dist):0;
599 ///\name Query Functions
600 ///The result of the %BFS algorithm can be obtained using these
602 ///Before the use of these functions,
603 ///either run() or start() must be called.
607 ///Copies the shortest path to \c t into \c p
609 ///This function copies the shortest path to \c t into \c p.
610 ///If \c t is a source itself or unreachable, then it does not
612 ///\return Returns \c true if a path to \c t was actually copied to \c p,
613 ///\c false otherwise.
616 bool getPath(P &p,Node t)
620 typename P::Builder b(p);
621 for(b.setStartNode(t);predEdge(t)!=INVALID;t=predNode(t))
622 b.pushFront(predEdge(t));
629 ///The distance of a node from the root(s).
631 ///Returns the distance of a node from the root(s).
632 ///\pre \ref run() must be called before using this function.
633 ///\warning If node \c v in unreachable from the root(s) the return value
634 ///of this function is undefined.
635 int dist(Node v) const { return (*_dist)[v]; }
637 ///Returns the 'previous edge' of the shortest path tree.
639 ///For a node \c v it returns the 'previous edge'
640 ///of the shortest path tree,
641 ///i.e. it returns the last edge of a shortest path from the root(s) to \c
642 ///v. It is \ref INVALID
643 ///if \c v is unreachable from the root(s) or \c v is a root. The
644 ///shortest path tree used here is equal to the shortest path tree used in
646 ///\pre Either \ref run() or \ref start() must be called before using
648 Edge predEdge(Node v) const { return (*_pred)[v];}
650 ///Returns the 'previous node' of the shortest path tree.
652 ///For a node \c v it returns the 'previous node'
653 ///of the shortest path tree,
654 ///i.e. it returns the last but one node from a shortest path from the
656 ///It is INVALID if \c v is unreachable from the root(s) or
657 ///if \c v itself a root.
658 ///The shortest path tree used here is equal to the shortest path
659 ///tree used in \ref predEdge().
660 ///\pre Either \ref run() or \ref start() must be called before
661 ///using this function.
662 Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID:
663 G->source((*_pred)[v]); }
665 ///Returns a reference to the NodeMap of distances.
667 ///Returns a reference to the NodeMap of distances.
668 ///\pre Either \ref run() or \ref init() must
669 ///be called before using this function.
670 const DistMap &distMap() const { return *_dist;}
672 ///Returns a reference to the shortest path tree map.
674 ///Returns a reference to the NodeMap of the edges of the
675 ///shortest path tree.
676 ///\pre Either \ref run() or \ref init()
677 ///must be called before using this function.
678 const PredMap &predMap() const { return *_pred;}
680 ///Checks if a node is reachable from the root.
682 ///Returns \c true if \c v is reachable from the root.
683 ///\warning The source nodes are indicated as unreached.
684 ///\pre Either \ref run() or \ref start()
685 ///must be called before using this function.
687 bool reached(Node v) { return (*_reached)[v]; }
692 ///Default traits class of Bfs function.
694 ///Default traits class of Bfs function.
695 ///\param GR Graph type.
697 struct BfsWizardDefaultTraits
699 ///The graph type the algorithm runs on.
701 ///\brief The type of the map that stores the last
702 ///edges of the shortest paths.
704 ///The type of the map that stores the last
705 ///edges of the shortest paths.
706 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
708 typedef NullMap<typename Graph::Node,typename GR::Edge> PredMap;
709 ///Instantiates a PredMap.
711 ///This function instantiates a \ref PredMap.
712 ///\param g is the graph, to which we would like to define the PredMap.
713 ///\todo The graph alone may be insufficient to initialize
715 static PredMap *createPredMap(const GR &g)
717 static PredMap *createPredMap(const GR &)
720 return new PredMap();
723 ///The type of the map that indicates which nodes are processed.
725 ///The type of the map that indicates which nodes are processed.
726 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
727 ///\todo named parameter to set this type, function to read and write.
728 typedef NullMap<typename Graph::Node,bool> ProcessedMap;
729 ///Instantiates a ProcessedMap.
731 ///This function instantiates a \ref ProcessedMap.
732 ///\param g is the graph, to which
733 ///we would like to define the \ref ProcessedMap
735 static ProcessedMap *createProcessedMap(const GR &g)
737 static ProcessedMap *createProcessedMap(const GR &)
740 return new ProcessedMap();
742 ///The type of the map that indicates which nodes are reached.
744 ///The type of the map that indicates which nodes are reached.
745 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
746 ///\todo named parameter to set this type, function to read and write.
747 typedef typename Graph::template NodeMap<bool> ReachedMap;
748 ///Instantiates a ReachedMap.
750 ///This function instantiates a \ref ReachedMap.
751 ///\param G is the graph, to which
752 ///we would like to define the \ref ReachedMap.
753 static ReachedMap *createReachedMap(const GR &G)
755 return new ReachedMap(G);
757 ///The type of the map that stores the dists of the nodes.
759 ///The type of the map that stores the dists of the nodes.
760 ///It must meet the \ref concept::WriteMap "WriteMap" concept.
762 typedef NullMap<typename Graph::Node,int> DistMap;
763 ///Instantiates a DistMap.
765 ///This function instantiates a \ref DistMap.
766 ///\param g is the graph, to which we would like to define the \ref DistMap
768 static DistMap *createDistMap(const GR &g)
770 static DistMap *createDistMap(const GR &)
773 return new DistMap();
777 /// Default traits used by \ref BfsWizard
779 /// To make it easier to use Bfs algorithm
780 ///we have created a wizard class.
781 /// This \ref BfsWizard class needs default traits,
782 ///as well as the \ref Bfs class.
783 /// The \ref BfsWizardBase is a class to be the default traits of the
784 /// \ref BfsWizard class.
786 class BfsWizardBase : public BfsWizardDefaultTraits<GR>
789 typedef BfsWizardDefaultTraits<GR> Base;
791 /// Type of the nodes in the graph.
792 typedef typename Base::Graph::Node Node;
794 /// Pointer to the underlying graph.
796 ///Pointer to the map of reached nodes.
798 ///Pointer to the map of processed nodes.
800 ///Pointer to the map of predecessors edges.
802 ///Pointer to the map of distances.
804 ///Pointer to the source node.
810 /// This constructor does not require parameters, therefore it initiates
811 /// all of the attributes to default values (0, INVALID).
812 BfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0),
813 _dist(0), _source(INVALID) {}
817 /// This constructor requires some parameters,
818 /// listed in the parameters list.
819 /// Others are initiated to 0.
820 /// \param g is the initial value of \ref _g
821 /// \param s is the initial value of \ref _source
822 BfsWizardBase(const GR &g, Node s=INVALID) :
823 _g((void *)&g), _reached(0), _processed(0), _pred(0),
824 _dist(0), _source(s) {}
828 /// A class to make the usage of Bfs algorithm easier
830 /// This class is created to make it easier to use Bfs algorithm.
831 /// It uses the functions and features of the plain \ref Bfs,
832 /// but it is much simpler to use it.
834 /// Simplicity means that the way to change the types defined
835 /// in the traits class is based on functions that returns the new class
836 /// and not on templatable built-in classes.
837 /// When using the plain \ref Bfs
838 /// the new class with the modified type comes from
839 /// the original class by using the ::
840 /// operator. In the case of \ref BfsWizard only
841 /// a function have to be called and it will
842 /// return the needed class.
844 /// It does not have own \ref run method. When its \ref run method is called
845 /// it initiates a plain \ref Bfs class, and calls the \ref Bfs::run
848 class BfsWizard : public TR
852 ///The type of the underlying graph.
853 typedef typename TR::Graph Graph;
855 typedef typename Graph::Node Node;
857 typedef typename Graph::NodeIt NodeIt;
859 typedef typename Graph::Edge Edge;
861 typedef typename Graph::OutEdgeIt OutEdgeIt;
863 ///\brief The type of the map that stores
865 typedef typename TR::ReachedMap ReachedMap;
866 ///\brief The type of the map that stores
867 ///the processed nodes
868 typedef typename TR::ProcessedMap ProcessedMap;
869 ///\brief The type of the map that stores the last
870 ///edges of the shortest paths.
871 typedef typename TR::PredMap PredMap;
872 ///The type of the map that stores the dists of the nodes.
873 typedef typename TR::DistMap DistMap;
877 BfsWizard() : TR() {}
879 /// Constructor that requires parameters.
881 /// Constructor that requires parameters.
882 /// These parameters will be the default values for the traits class.
883 BfsWizard(const Graph &g, Node s=INVALID) :
887 BfsWizard(const TR &b) : TR(b) {}
891 ///Runs Bfs algorithm from a given node.
893 ///Runs Bfs algorithm from a given node.
894 ///The node can be given by the \ref source function.
897 if(Base::_source==INVALID) throw UninitializedParameter();
898 Bfs<Graph,TR> alg(*(Graph*)Base::_g);
900 alg.reachedMap(*(ReachedMap*)Base::_reached);
901 if(Base::_processed) alg.processedMap(*(ProcessedMap*)Base::_processed);
902 if(Base::_pred) alg.predMap(*(PredMap*)Base::_pred);
903 if(Base::_dist) alg.distMap(*(DistMap*)Base::_dist);
904 alg.run(Base::_source);
907 ///Runs Bfs algorithm from the given node.
909 ///Runs Bfs algorithm from the given node.
910 ///\param s is the given source.
918 struct DefPredMapBase : public Base {
920 static PredMap *createPredMap(const Graph &) { return 0; };
921 DefPredMapBase(const TR &b) : TR(b) {}
924 ///\brief \ref named-templ-param "Named parameter"
925 ///function for setting PredMap
927 /// \ref named-templ-param "Named parameter"
928 ///function for setting PredMap
931 BfsWizard<DefPredMapBase<T> > predMap(const T &t)
933 Base::_pred=(void *)&t;
934 return BfsWizard<DefPredMapBase<T> >(*this);
939 struct DefReachedMapBase : public Base {
940 typedef T ReachedMap;
941 static ReachedMap *createReachedMap(const Graph &) { return 0; };
942 DefReachedMapBase(const TR &b) : TR(b) {}
945 ///\brief \ref named-templ-param "Named parameter"
946 ///function for setting ReachedMap
948 /// \ref named-templ-param "Named parameter"
949 ///function for setting ReachedMap
952 BfsWizard<DefReachedMapBase<T> > reachedMap(const T &t)
954 Base::_pred=(void *)&t;
955 return BfsWizard<DefReachedMapBase<T> >(*this);
960 struct DefProcessedMapBase : public Base {
961 typedef T ProcessedMap;
962 static ProcessedMap *createProcessedMap(const Graph &) { return 0; };
963 DefProcessedMapBase(const TR &b) : TR(b) {}
966 ///\brief \ref named-templ-param "Named parameter"
967 ///function for setting ProcessedMap
969 /// \ref named-templ-param "Named parameter"
970 ///function for setting ProcessedMap
973 BfsWizard<DefProcessedMapBase<T> > processedMap(const T &t)
975 Base::_pred=(void *)&t;
976 return BfsWizard<DefProcessedMapBase<T> >(*this);
981 struct DefDistMapBase : public Base {
983 static DistMap *createDistMap(const Graph &) { return 0; };
984 DefDistMapBase(const TR &b) : TR(b) {}
987 ///\brief \ref named-templ-param "Named parameter"
988 ///function for setting DistMap type
990 /// \ref named-templ-param "Named parameter"
991 ///function for setting DistMap type
994 BfsWizard<DefDistMapBase<T> > distMap(const T &t)
996 Base::_dist=(void *)&t;
997 return BfsWizard<DefDistMapBase<T> >(*this);
1000 /// Sets the source node, from which the Bfs algorithm runs.
1002 /// Sets the source node, from which the Bfs algorithm runs.
1003 /// \param s is the source node.
1004 BfsWizard<TR> &source(Node s)
1012 ///Function type interface for Bfs algorithm.
1014 /// \ingroup flowalgs
1015 ///Function type interface for Bfs algorithm.
1017 ///This function also has several
1018 ///\ref named-templ-func-param "named parameters",
1019 ///they are declared as the members of class \ref BfsWizard.
1021 ///example shows how to use these parameters.
1023 /// bfs(g,source).predMap(preds).run();
1025 ///\warning Don't forget to put the \ref BfsWizard::run() "run()"
1026 ///to the end of the parameter list.
1030 BfsWizard<BfsWizardBase<GR> >
1031 bfs(const GR &g,typename GR::Node s=INVALID)
1033 return BfsWizard<BfsWizardBase<GR> >(g,s);
1036 } //END OF NAMESPACE LEMON