Revert to long long int since currently I don't know a better solution.
3 * This file is a part of LEMON, a generic C++ optimization library
5 * Copyright (C) 2003-2008
6 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 * (Egervary Research Group on Combinatorial Optimization, EGRES).
9 * Permission to use, modify and distribute this software is granted
10 * provided that this copyright notice appears in all copies. For
11 * precise terms see the accompanying LICENSE file.
13 * This software is provided "AS IS" with no warranty of any kind,
14 * express or implied, and with no claim as to its suitability for any
19 #ifndef LEMON_DIJKSTRA_H
20 #define LEMON_DIJKSTRA_H
22 ///\ingroup shortest_path
24 ///\brief Dijkstra algorithm.
27 #include <lemon/list_graph.h>
28 #include <lemon/bin_heap.h>
29 #include <lemon/bits/path_dump.h>
30 #include <lemon/bits/invalid.h>
31 #include <lemon/error.h>
32 #include <lemon/maps.h>
37 /// \brief Default OperationTraits for the Dijkstra algorithm class.
39 /// It defines all computational operations and constants which are
40 /// used in the Dijkstra algorithm.
41 template <typename Value>
42 struct DijkstraDefaultOperationTraits {
43 /// \brief Gives back the zero value of the type.
45 return static_cast<Value>(0);
47 /// \brief Gives back the sum of the given two elements.
48 static Value plus(const Value& left, const Value& right) {
51 /// \brief Gives back true only if the first value less than the second.
52 static bool less(const Value& left, const Value& right) {
57 /// \brief Widest path OperationTraits for the Dijkstra algorithm class.
59 /// It defines all computational operations and constants which are
60 /// used in the Dijkstra algorithm for widest path computation.
61 template <typename Value>
62 struct DijkstraWidestPathOperationTraits {
63 /// \brief Gives back the maximum value of the type.
65 return std::numeric_limits<Value>::max();
67 /// \brief Gives back the minimum of the given two elements.
68 static Value plus(const Value& left, const Value& right) {
69 return std::min(left, right);
71 /// \brief Gives back true only if the first value less than the second.
72 static bool less(const Value& left, const Value& right) {
77 ///Default traits class of Dijkstra class.
79 ///Default traits class of Dijkstra class.
80 ///\param GR Graph type.
81 ///\param LM Type of length map.
82 template<class GR, class LM>
83 struct DijkstraDefaultTraits
85 ///The graph type the algorithm runs on.
87 ///The type of the map that stores the edge lengths.
89 ///The type of the map that stores the edge lengths.
90 ///It must meet the \ref concepts::ReadMap "ReadMap" concept.
92 //The type of the length of the edges.
93 typedef typename LM::Value Value;
94 /// Operation traits for Dijkstra algorithm.
96 /// It defines the used operation by the algorithm.
97 /// \see DijkstraDefaultOperationTraits
98 typedef DijkstraDefaultOperationTraits<Value> OperationTraits;
99 /// The cross reference type used by heap.
102 /// The cross reference type used by heap.
103 /// Usually it is \c Graph::NodeMap<int>.
104 typedef typename Graph::template NodeMap<int> HeapCrossRef;
105 ///Instantiates a HeapCrossRef.
107 ///This function instantiates a \c HeapCrossRef.
108 /// \param G is the graph, to which we would like to define the
110 static HeapCrossRef *createHeapCrossRef(const GR &G)
112 return new HeapCrossRef(G);
115 ///The heap type used by Dijkstra algorithm.
117 ///The heap type used by Dijkstra algorithm.
121 typedef BinHeap<typename LM::Value, HeapCrossRef, std::less<Value> > Heap;
123 static Heap *createHeap(HeapCrossRef& R)
128 ///\brief The type of the map that stores the last
129 ///edges of the shortest paths.
131 ///The type of the map that stores the last
132 ///edges of the shortest paths.
133 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
135 typedef typename Graph::template NodeMap<typename GR::Edge> PredMap;
136 ///Instantiates a PredMap.
138 ///This function instantiates a \c PredMap.
139 ///\param G is the graph, to which we would like to define the PredMap.
140 ///\todo The graph alone may be insufficient for the initialization
141 static PredMap *createPredMap(const GR &G)
143 return new PredMap(G);
146 ///The type of the map that stores whether a nodes is processed.
148 ///The type of the map that stores whether a nodes is processed.
149 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
150 ///By default it is a NullMap.
151 ///\todo If it is set to a real map,
152 ///Dijkstra::processed() should read this.
153 ///\todo named parameter to set this type, function to read and write.
154 typedef NullMap<typename Graph::Node,bool> ProcessedMap;
155 ///Instantiates a ProcessedMap.
157 ///This function instantiates a \c ProcessedMap.
158 ///\param g is the graph, to which
159 ///we would like to define the \c ProcessedMap
161 static ProcessedMap *createProcessedMap(const GR &g)
163 static ProcessedMap *createProcessedMap(const GR &)
166 return new ProcessedMap();
168 ///The type of the map that stores the dists of the nodes.
170 ///The type of the map that stores the dists of the nodes.
171 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
173 typedef typename Graph::template NodeMap<typename LM::Value> DistMap;
174 ///Instantiates a DistMap.
176 ///This function instantiates a \ref DistMap.
177 ///\param G is the graph, to which we would like to define the \ref DistMap
178 static DistMap *createDistMap(const GR &G)
180 return new DistMap(G);
184 ///%Dijkstra algorithm class.
186 /// \ingroup shortest_path
187 ///This class provides an efficient implementation of %Dijkstra algorithm.
188 ///The edge lengths are passed to the algorithm using a
189 ///\ref concepts::ReadMap "ReadMap",
190 ///so it is easy to change it to any kind of length.
192 ///The type of the length is determined by the
193 ///\ref concepts::ReadMap::Value "Value" of the length map.
195 ///It is also possible to change the underlying priority heap.
197 ///\param GR The graph type the algorithm runs on. The default value
198 ///is \ref ListGraph. The value of GR is not used directly by
199 ///Dijkstra, it is only passed to \ref DijkstraDefaultTraits.
200 ///\param LM This read-only EdgeMap determines the lengths of the
201 ///edges. It is read once for each edge, so the map may involve in
202 ///relatively time consuming process to compute the edge length if
203 ///it is necessary. The default map type is \ref
204 ///concepts::Graph::EdgeMap "Graph::EdgeMap<int>". The value
205 ///of LM is not used directly by Dijkstra, it is only passed to \ref
206 ///DijkstraDefaultTraits. \param TR Traits class to set
207 ///various data types used by the algorithm. The default traits
208 ///class is \ref DijkstraDefaultTraits
209 ///"DijkstraDefaultTraits<GR,LM>". See \ref
210 ///DijkstraDefaultTraits for the documentation of a Dijkstra traits
213 ///\author Jacint Szabo and Alpar Juttner
216 template <typename GR, typename LM, typename TR>
218 template <typename GR=ListGraph,
219 typename LM=typename GR::template EdgeMap<int>,
220 typename TR=DijkstraDefaultTraits<GR,LM> >
225 * \brief \ref Exception for uninitialized parameters.
227 * This error represents problems in the initialization
228 * of the parameters of the algorithms.
230 class UninitializedParameter : public lemon::UninitializedParameter {
232 virtual const char* what() const throw() {
233 return "lemon::Dijkstra::UninitializedParameter";
238 ///The type of the underlying graph.
239 typedef typename TR::Graph Graph;
241 typedef typename Graph::Node Node;
243 typedef typename Graph::NodeIt NodeIt;
245 typedef typename Graph::Edge Edge;
247 typedef typename Graph::OutEdgeIt OutEdgeIt;
249 ///The type of the length of the edges.
250 typedef typename TR::LengthMap::Value Value;
251 ///The type of the map that stores the edge lengths.
252 typedef typename TR::LengthMap LengthMap;
253 ///\brief The type of the map that stores the last
254 ///edges of the shortest paths.
255 typedef typename TR::PredMap PredMap;
256 ///The type of the map indicating if a node is processed.
257 typedef typename TR::ProcessedMap ProcessedMap;
258 ///The type of the map that stores the dists of the nodes.
259 typedef typename TR::DistMap DistMap;
260 ///The cross reference type used for the current heap.
261 typedef typename TR::HeapCrossRef HeapCrossRef;
262 ///The heap type used by the dijkstra algorithm.
263 typedef typename TR::Heap Heap;
264 ///The operation traits.
265 typedef typename TR::OperationTraits OperationTraits;
267 /// Pointer to the underlying graph.
269 /// Pointer to the length map
270 const LengthMap *length;
271 ///Pointer to the map of predecessors edges.
273 ///Indicates if \ref _pred is locally allocated (\c true) or not.
275 ///Pointer to the map of distances.
277 ///Indicates if \ref _dist is locally allocated (\c true) or not.
279 ///Pointer to the map of processed status of the nodes.
280 ProcessedMap *_processed;
281 ///Indicates if \ref _processed is locally allocated (\c true) or not.
282 bool local_processed;
283 ///Pointer to the heap cross references.
284 HeapCrossRef *_heap_cross_ref;
285 ///Indicates if \ref _heap_cross_ref is locally allocated (\c true) or not.
286 bool local_heap_cross_ref;
287 ///Pointer to the heap.
289 ///Indicates if \ref _heap is locally allocated (\c true) or not.
292 ///Creates the maps if necessary.
294 ///\todo Better memory allocation (instead of new).
299 _pred = Traits::createPredMap(*G);
303 _dist = Traits::createDistMap(*G);
306 local_processed = true;
307 _processed = Traits::createProcessedMap(*G);
309 if (!_heap_cross_ref) {
310 local_heap_cross_ref = true;
311 _heap_cross_ref = Traits::createHeapCrossRef(*G);
315 _heap = Traits::createHeap(*_heap_cross_ref);
321 typedef Dijkstra Create;
323 ///\name Named template parameters
328 struct DefPredMapTraits : public Traits {
330 static PredMap *createPredMap(const Graph &)
332 throw UninitializedParameter();
335 ///\ref named-templ-param "Named parameter" for setting PredMap type
337 ///\ref named-templ-param "Named parameter" for setting PredMap type
341 : public Dijkstra< Graph, LengthMap, DefPredMapTraits<T> > {
342 typedef Dijkstra< Graph, LengthMap, DefPredMapTraits<T> > Create;
346 struct DefDistMapTraits : public Traits {
348 static DistMap *createDistMap(const Graph &)
350 throw UninitializedParameter();
353 ///\ref named-templ-param "Named parameter" for setting DistMap type
355 ///\ref named-templ-param "Named parameter" for setting DistMap type
359 : public Dijkstra< Graph, LengthMap, DefDistMapTraits<T> > {
360 typedef Dijkstra< Graph, LengthMap, DefDistMapTraits<T> > Create;
364 struct DefProcessedMapTraits : public Traits {
365 typedef T ProcessedMap;
366 static ProcessedMap *createProcessedMap(const Graph &G)
368 throw UninitializedParameter();
371 ///\ref named-templ-param "Named parameter" for setting ProcessedMap type
373 ///\ref named-templ-param "Named parameter" for setting ProcessedMap type
376 struct DefProcessedMap
377 : public Dijkstra< Graph, LengthMap, DefProcessedMapTraits<T> > {
378 typedef Dijkstra< Graph, LengthMap, DefProcessedMapTraits<T> > Create;
381 struct DefGraphProcessedMapTraits : public Traits {
382 typedef typename Graph::template NodeMap<bool> ProcessedMap;
383 static ProcessedMap *createProcessedMap(const Graph &G)
385 return new ProcessedMap(G);
388 ///\brief \ref named-templ-param "Named parameter"
389 ///for setting the ProcessedMap type to be Graph::NodeMap<bool>.
391 ///\ref named-templ-param "Named parameter"
392 ///for setting the ProcessedMap type to be Graph::NodeMap<bool>.
393 ///If you don't set it explicitely, it will be automatically allocated.
395 struct DefProcessedMapToBeDefaultMap
396 : public Dijkstra< Graph, LengthMap, DefGraphProcessedMapTraits> {
397 typedef Dijkstra< Graph, LengthMap, DefGraphProcessedMapTraits> Create;
400 template <class H, class CR>
401 struct DefHeapTraits : public Traits {
402 typedef CR HeapCrossRef;
404 static HeapCrossRef *createHeapCrossRef(const Graph &) {
405 throw UninitializedParameter();
407 static Heap *createHeap(HeapCrossRef &)
409 throw UninitializedParameter();
412 ///\brief \ref named-templ-param "Named parameter" for setting
413 ///heap and cross reference type
415 ///\ref named-templ-param "Named parameter" for setting heap and cross
418 template <class H, class CR = typename Graph::template NodeMap<int> >
420 : public Dijkstra< Graph, LengthMap, DefHeapTraits<H, CR> > {
421 typedef Dijkstra< Graph, LengthMap, DefHeapTraits<H, CR> > Create;
424 template <class H, class CR>
425 struct DefStandardHeapTraits : public Traits {
426 typedef CR HeapCrossRef;
428 static HeapCrossRef *createHeapCrossRef(const Graph &G) {
429 return new HeapCrossRef(G);
431 static Heap *createHeap(HeapCrossRef &R)
436 ///\brief \ref named-templ-param "Named parameter" for setting
437 ///heap and cross reference type with automatic allocation
439 ///\ref named-templ-param "Named parameter" for setting heap and cross
440 ///reference type. It can allocate the heap and the cross reference
441 ///object if the cross reference's constructor waits for the graph as
442 ///parameter and the heap's constructor waits for the cross reference.
443 template <class H, class CR = typename Graph::template NodeMap<int> >
444 struct DefStandardHeap
445 : public Dijkstra< Graph, LengthMap, DefStandardHeapTraits<H, CR> > {
446 typedef Dijkstra< Graph, LengthMap, DefStandardHeapTraits<H, CR> >
451 struct DefOperationTraitsTraits : public Traits {
452 typedef T OperationTraits;
455 /// \brief \ref named-templ-param "Named parameter" for setting
456 /// OperationTraits type
458 /// \ref named-templ-param "Named parameter" for setting OperationTraits
461 struct DefOperationTraits
462 : public Dijkstra<Graph, LengthMap, DefOperationTraitsTraits<T> > {
463 typedef Dijkstra<Graph, LengthMap, DefOperationTraitsTraits<T> >
478 ///\param _G the graph the algorithm will run on.
479 ///\param _length the length map used by the algorithm.
480 Dijkstra(const Graph& _G, const LengthMap& _length) :
481 G(&_G), length(&_length),
482 _pred(NULL), local_pred(false),
483 _dist(NULL), local_dist(false),
484 _processed(NULL), local_processed(false),
485 _heap_cross_ref(NULL), local_heap_cross_ref(false),
486 _heap(NULL), local_heap(false)
492 if(local_pred) delete _pred;
493 if(local_dist) delete _dist;
494 if(local_processed) delete _processed;
495 if(local_heap_cross_ref) delete _heap_cross_ref;
496 if(local_heap) delete _heap;
499 ///Sets the length map.
501 ///Sets the length map.
502 ///\return <tt> (*this) </tt>
503 Dijkstra &lengthMap(const LengthMap &m)
509 ///Sets the map storing the predecessor edges.
511 ///Sets the map storing the predecessor edges.
512 ///If you don't use this function before calling \ref run(),
513 ///it will allocate one. The destuctor deallocates this
514 ///automatically allocated map, of course.
515 ///\return <tt> (*this) </tt>
516 Dijkstra &predMap(PredMap &m)
526 ///Sets the map storing the distances calculated by the algorithm.
528 ///Sets the map storing the distances calculated by the algorithm.
529 ///If you don't use this function before calling \ref run(),
530 ///it will allocate one. The destuctor deallocates this
531 ///automatically allocated map, of course.
532 ///\return <tt> (*this) </tt>
533 Dijkstra &distMap(DistMap &m)
543 ///Sets the heap and the cross reference used by algorithm.
545 ///Sets the heap and the cross reference used by algorithm.
546 ///If you don't use this function before calling \ref run(),
547 ///it will allocate one. The destuctor deallocates this
548 ///automatically allocated heap and cross reference, of course.
549 ///\return <tt> (*this) </tt>
550 Dijkstra &heap(Heap& hp, HeapCrossRef &cr)
552 if(local_heap_cross_ref) {
553 delete _heap_cross_ref;
554 local_heap_cross_ref=false;
556 _heap_cross_ref = &cr;
566 void finalizeNodeData(Node v,Value dst)
568 _processed->set(v,true);
574 typedef PredMapPath<Graph, PredMap> Path;
576 ///\name Execution control
577 ///The simplest way to execute the algorithm is to use
578 ///one of the member functions called \c run(...).
580 ///If you need more control on the execution,
581 ///first you must call \ref init(), then you can add several source nodes
582 ///with \ref addSource().
583 ///Finally \ref start() will perform the actual path
588 ///Initializes the internal data structures.
590 ///Initializes the internal data structures.
596 for ( NodeIt u(*G) ; u!=INVALID ; ++u ) {
597 _pred->set(u,INVALID);
598 _processed->set(u,false);
599 _heap_cross_ref->set(u,Heap::PRE_HEAP);
603 ///Adds a new source node.
605 ///Adds a new source node to the priority heap.
607 ///The optional second parameter is the initial distance of the node.
609 ///It checks if the node has already been added to the heap and
610 ///it is pushed to the heap only if either it was not in the heap
611 ///or the shortest path found till then is shorter than \c dst.
612 void addSource(Node s,Value dst=OperationTraits::zero())
614 if(_heap->state(s) != Heap::IN_HEAP) {
616 } else if(OperationTraits::less((*_heap)[s], dst)) {
618 _pred->set(s,INVALID);
622 ///Processes the next node in the priority heap
624 ///Processes the next node in the priority heap.
626 ///\return The processed node.
628 ///\warning The priority heap must not be empty!
629 Node processNextNode()
632 Value oldvalue=_heap->prio();
634 finalizeNodeData(v,oldvalue);
636 for(OutEdgeIt e(*G,v); e!=INVALID; ++e) {
638 switch(_heap->state(w)) {
640 _heap->push(w,OperationTraits::plus(oldvalue, (*length)[e]));
645 Value newvalue = OperationTraits::plus(oldvalue, (*length)[e]);
646 if ( OperationTraits::less(newvalue, (*_heap)[w]) ) {
647 _heap->decrease(w, newvalue);
652 case Heap::POST_HEAP:
659 ///Next node to be processed.
661 ///Next node to be processed.
663 ///\return The next node to be processed or INVALID if the priority heap
667 return !_heap->empty()?_heap->top():INVALID;
670 ///\brief Returns \c false if there are nodes
671 ///to be processed in the priority heap
673 ///Returns \c false if there are nodes
674 ///to be processed in the priority heap
675 bool emptyQueue() { return _heap->empty(); }
676 ///Returns the number of the nodes to be processed in the priority heap
678 ///Returns the number of the nodes to be processed in the priority heap
680 int queueSize() { return _heap->size(); }
682 ///Executes the algorithm.
684 ///Executes the algorithm.
686 ///\pre init() must be called and at least one node should be added
687 ///with addSource() before using this function.
689 ///This method runs the %Dijkstra algorithm from the root node(s)
692 ///shortest path to each node. The algorithm computes
693 ///- The shortest path tree.
694 ///- The distance of each node from the root(s).
698 while ( !_heap->empty() ) processNextNode();
701 ///Executes the algorithm until \c dest is reached.
703 ///Executes the algorithm until \c dest is reached.
705 ///\pre init() must be called and at least one node should be added
706 ///with addSource() before using this function.
708 ///This method runs the %Dijkstra algorithm from the root node(s)
711 ///shortest path to \c dest. The algorithm computes
712 ///- The shortest path to \c dest.
713 ///- The distance of \c dest from the root(s).
715 void start(Node dest)
717 while ( !_heap->empty() && _heap->top()!=dest ) processNextNode();
718 if ( !_heap->empty() ) finalizeNodeData(_heap->top(),_heap->prio());
721 ///Executes the algorithm until a condition is met.
723 ///Executes the algorithm until a condition is met.
725 ///\pre init() must be called and at least one node should be added
726 ///with addSource() before using this function.
728 ///\param nm must be a bool (or convertible) node map. The algorithm
729 ///will stop when it reaches a node \c v with <tt>nm[v]</tt> true.
731 ///\return The reached node \c v with <tt>nm[v]</tt> true or
732 ///\c INVALID if no such node was found.
733 template<class NodeBoolMap>
734 Node start(const NodeBoolMap &nm)
736 while ( !_heap->empty() && !nm[_heap->top()] ) processNextNode();
737 if ( _heap->empty() ) return INVALID;
738 finalizeNodeData(_heap->top(),_heap->prio());
742 ///Runs %Dijkstra algorithm from node \c s.
744 ///This method runs the %Dijkstra algorithm from a root node \c s
747 ///shortest path to each node. The algorithm computes
748 ///- The shortest path tree.
749 ///- The distance of each node from the root.
751 ///\note d.run(s) is just a shortcut of the following code.
763 ///Finds the shortest path between \c s and \c t.
765 ///Finds the shortest path between \c s and \c t.
767 ///\return The length of the shortest s---t path if there exists one,
769 ///\note Apart from the return value, d.run(s) is
770 ///just a shortcut of the following code.
776 Value run(Node s,Node t) {
780 return (*_pred)[t]==INVALID?OperationTraits::zero():(*_dist)[t];
785 ///\name Query Functions
786 ///The result of the %Dijkstra algorithm can be obtained using these
788 ///Before the use of these functions,
789 ///either run() or start() must be called.
793 ///Gives back the shortest path.
795 ///Gives back the shortest path.
796 ///\pre The \c t should be reachable from the source.
799 return Path(*G, *_pred, t);
802 ///The distance of a node from the root.
804 ///Returns the distance of a node from the root.
805 ///\pre \ref run() must be called before using this function.
806 ///\warning If node \c v in unreachable from the root the return value
807 ///of this funcion is undefined.
808 Value dist(Node v) const { return (*_dist)[v]; }
810 ///The current distance of a node from the root.
812 ///Returns the current distance of a node from the root.
813 ///It may be decreased in the following processes.
814 ///\pre \c node should be reached but not processed
815 Value currentDist(Node v) const { return (*_heap)[v]; }
817 ///Returns the 'previous edge' of the shortest path tree.
819 ///For a node \c v it returns the 'previous edge' of the shortest path tree,
820 ///i.e. it returns the last edge of a shortest path from the root to \c
821 ///v. It is \ref INVALID
822 ///if \c v is unreachable from the root or if \c v=s. The
823 ///shortest path tree used here is equal to the shortest path tree used in
824 ///\ref predNode(). \pre \ref run() must be called before using
826 Edge predEdge(Node v) const { return (*_pred)[v]; }
828 ///Returns the 'previous node' of the shortest path tree.
830 ///For a node \c v it returns the 'previous node' of the shortest path tree,
831 ///i.e. it returns the last but one node from a shortest path from the
832 ///root to \c /v. It is INVALID if \c v is unreachable from the root or if
833 ///\c v=s. The shortest path tree used here is equal to the shortest path
834 ///tree used in \ref predEdge(). \pre \ref run() must be called before
835 ///using this function.
836 Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID:
837 G->source((*_pred)[v]); }
839 ///Returns a reference to the NodeMap of distances.
841 ///Returns a reference to the NodeMap of distances. \pre \ref run() must
842 ///be called before using this function.
843 const DistMap &distMap() const { return *_dist;}
845 ///Returns a reference to the shortest path tree map.
847 ///Returns a reference to the NodeMap of the edges of the
848 ///shortest path tree.
849 ///\pre \ref run() must be called before using this function.
850 const PredMap &predMap() const { return *_pred;}
852 ///Checks if a node is reachable from the root.
854 ///Returns \c true if \c v is reachable from the root.
855 ///\warning The source nodes are inditated as unreached.
856 ///\pre \ref run() must be called before using this function.
858 bool reached(Node v) { return (*_heap_cross_ref)[v] != Heap::PRE_HEAP; }
860 ///Checks if a node is processed.
862 ///Returns \c true if \c v is processed, i.e. the shortest
863 ///path to \c v has already found.
864 ///\pre \ref run() must be called before using this function.
866 bool processed(Node v) { return (*_heap_cross_ref)[v] == Heap::POST_HEAP; }
875 ///Default traits class of Dijkstra function.
877 ///Default traits class of Dijkstra function.
878 ///\param GR Graph type.
879 ///\param LM Type of length map.
880 template<class GR, class LM>
881 struct DijkstraWizardDefaultTraits
883 ///The graph type the algorithm runs on.
885 ///The type of the map that stores the edge lengths.
887 ///The type of the map that stores the edge lengths.
888 ///It must meet the \ref concepts::ReadMap "ReadMap" concept.
889 typedef LM LengthMap;
890 //The type of the length of the edges.
891 typedef typename LM::Value Value;
892 /// Operation traits for Dijkstra algorithm.
894 /// It defines the used operation by the algorithm.
895 /// \see DijkstraDefaultOperationTraits
896 typedef DijkstraDefaultOperationTraits<Value> OperationTraits;
897 ///The heap type used by Dijkstra algorithm.
899 /// The cross reference type used by heap.
901 /// The cross reference type used by heap.
902 /// Usually it is \c Graph::NodeMap<int>.
903 typedef typename Graph::template NodeMap<int> HeapCrossRef;
904 ///Instantiates a HeapCrossRef.
906 ///This function instantiates a \ref HeapCrossRef.
907 /// \param G is the graph, to which we would like to define the
909 /// \todo The graph alone may be insufficient for the initialization
910 static HeapCrossRef *createHeapCrossRef(const GR &G)
912 return new HeapCrossRef(G);
915 ///The heap type used by Dijkstra algorithm.
917 ///The heap type used by Dijkstra algorithm.
921 typedef BinHeap<typename LM::Value, typename GR::template NodeMap<int>,
922 std::less<Value> > Heap;
924 static Heap *createHeap(HeapCrossRef& R)
929 ///\brief The type of the map that stores the last
930 ///edges of the shortest paths.
932 ///The type of the map that stores the last
933 ///edges of the shortest paths.
934 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
936 typedef NullMap <typename GR::Node,typename GR::Edge> PredMap;
937 ///Instantiates a PredMap.
939 ///This function instantiates a \ref PredMap.
940 ///\param g is the graph, to which we would like to define the PredMap.
941 ///\todo The graph alone may be insufficient for the initialization
943 static PredMap *createPredMap(const GR &g)
945 static PredMap *createPredMap(const GR &)
948 return new PredMap();
950 ///The type of the map that stores whether a nodes is processed.
952 ///The type of the map that stores whether a nodes is processed.
953 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
954 ///By default it is a NullMap.
955 ///\todo If it is set to a real map,
956 ///Dijkstra::processed() should read this.
957 ///\todo named parameter to set this type, function to read and write.
958 typedef NullMap<typename Graph::Node,bool> ProcessedMap;
959 ///Instantiates a ProcessedMap.
961 ///This function instantiates a \ref ProcessedMap.
962 ///\param g is the graph, to which
963 ///we would like to define the \ref ProcessedMap
965 static ProcessedMap *createProcessedMap(const GR &g)
967 static ProcessedMap *createProcessedMap(const GR &)
970 return new ProcessedMap();
972 ///The type of the map that stores the dists of the nodes.
974 ///The type of the map that stores the dists of the nodes.
975 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
977 typedef NullMap<typename Graph::Node,typename LM::Value> DistMap;
978 ///Instantiates a DistMap.
980 ///This function instantiates a \ref DistMap.
981 ///\param g is the graph, to which we would like to define the \ref DistMap
983 static DistMap *createDistMap(const GR &g)
985 static DistMap *createDistMap(const GR &)
988 return new DistMap();
992 /// Default traits used by \ref DijkstraWizard
994 /// To make it easier to use Dijkstra algorithm
995 ///we have created a wizard class.
996 /// This \ref DijkstraWizard class needs default traits,
997 ///as well as the \ref Dijkstra class.
998 /// The \ref DijkstraWizardBase is a class to be the default traits of the
999 /// \ref DijkstraWizard class.
1000 /// \todo More named parameters are required...
1001 template<class GR,class LM>
1002 class DijkstraWizardBase : public DijkstraWizardDefaultTraits<GR,LM>
1005 typedef DijkstraWizardDefaultTraits<GR,LM> Base;
1007 /// Type of the nodes in the graph.
1008 typedef typename Base::Graph::Node Node;
1010 /// Pointer to the underlying graph.
1012 /// Pointer to the length map
1014 ///Pointer to the map of predecessors edges.
1016 ///Pointer to the map of distances.
1018 ///Pointer to the source node.
1024 /// This constructor does not require parameters, therefore it initiates
1025 /// all of the attributes to default values (0, INVALID).
1026 DijkstraWizardBase() : _g(0), _length(0), _pred(0),
1027 _dist(0), _source(INVALID) {}
1031 /// This constructor requires some parameters,
1032 /// listed in the parameters list.
1033 /// Others are initiated to 0.
1034 /// \param g is the initial value of \ref _g
1035 /// \param l is the initial value of \ref _length
1036 /// \param s is the initial value of \ref _source
1037 DijkstraWizardBase(const GR &g,const LM &l, Node s=INVALID) :
1038 _g(reinterpret_cast<void*>(const_cast<GR*>(&g))),
1039 _length(reinterpret_cast<void*>(const_cast<LM*>(&l))),
1040 _pred(0), _dist(0), _source(s) {}
1044 /// A class to make the usage of Dijkstra algorithm easier
1046 /// This class is created to make it easier to use Dijkstra algorithm.
1047 /// It uses the functions and features of the plain \ref Dijkstra,
1048 /// but it is much simpler to use it.
1050 /// Simplicity means that the way to change the types defined
1051 /// in the traits class is based on functions that returns the new class
1052 /// and not on templatable built-in classes.
1053 /// When using the plain \ref Dijkstra
1054 /// the new class with the modified type comes from
1055 /// the original class by using the ::
1056 /// operator. In the case of \ref DijkstraWizard only
1057 /// a function have to be called and it will
1058 /// return the needed class.
1060 /// It does not have own \ref run method. When its \ref run method is called
1061 /// it initiates a plain \ref Dijkstra class, and calls the \ref
1062 /// Dijkstra::run method of it.
1064 class DijkstraWizard : public TR
1068 ///The type of the underlying graph.
1069 typedef typename TR::Graph Graph;
1071 typedef typename Graph::Node Node;
1073 typedef typename Graph::NodeIt NodeIt;
1075 typedef typename Graph::Edge Edge;
1077 typedef typename Graph::OutEdgeIt OutEdgeIt;
1079 ///The type of the map that stores the edge lengths.
1080 typedef typename TR::LengthMap LengthMap;
1081 ///The type of the length of the edges.
1082 typedef typename LengthMap::Value Value;
1083 ///\brief The type of the map that stores the last
1084 ///edges of the shortest paths.
1085 typedef typename TR::PredMap PredMap;
1086 ///The type of the map that stores the dists of the nodes.
1087 typedef typename TR::DistMap DistMap;
1088 ///The heap type used by the dijkstra algorithm.
1089 typedef typename TR::Heap Heap;
1092 DijkstraWizard() : TR() {}
1094 /// Constructor that requires parameters.
1096 /// Constructor that requires parameters.
1097 /// These parameters will be the default values for the traits class.
1098 DijkstraWizard(const Graph &g,const LengthMap &l, Node s=INVALID) :
1102 DijkstraWizard(const TR &b) : TR(b) {}
1104 ~DijkstraWizard() {}
1106 ///Runs Dijkstra algorithm from a given node.
1108 ///Runs Dijkstra algorithm from a given node.
1109 ///The node can be given by the \ref source function.
1112 if(Base::_source==INVALID) throw UninitializedParameter();
1113 Dijkstra<Graph,LengthMap,TR>
1114 dij(*reinterpret_cast<const Graph*>(Base::_g),
1115 *reinterpret_cast<const LengthMap*>(Base::_length));
1116 if(Base::_pred) dij.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
1117 if(Base::_dist) dij.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
1118 dij.run(Base::_source);
1121 ///Runs Dijkstra algorithm from the given node.
1123 ///Runs Dijkstra algorithm from the given node.
1124 ///\param s is the given source.
1132 struct DefPredMapBase : public Base {
1134 static PredMap *createPredMap(const Graph &) { return 0; };
1135 DefPredMapBase(const TR &b) : TR(b) {}
1138 ///\brief \ref named-templ-param "Named parameter"
1139 ///function for setting PredMap type
1141 /// \ref named-templ-param "Named parameter"
1142 ///function for setting PredMap type
1145 DijkstraWizard<DefPredMapBase<T> > predMap(const T &t)
1147 Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t));
1148 return DijkstraWizard<DefPredMapBase<T> >(*this);
1152 struct DefDistMapBase : public Base {
1154 static DistMap *createDistMap(const Graph &) { return 0; };
1155 DefDistMapBase(const TR &b) : TR(b) {}
1158 ///\brief \ref named-templ-param "Named parameter"
1159 ///function for setting DistMap type
1161 /// \ref named-templ-param "Named parameter"
1162 ///function for setting DistMap type
1165 DijkstraWizard<DefDistMapBase<T> > distMap(const T &t)
1167 Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t));
1168 return DijkstraWizard<DefDistMapBase<T> >(*this);
1171 /// Sets the source node, from which the Dijkstra algorithm runs.
1173 /// Sets the source node, from which the Dijkstra algorithm runs.
1174 /// \param s is the source node.
1175 DijkstraWizard<TR> &source(Node s)
1183 ///Function type interface for Dijkstra algorithm.
1185 /// \ingroup shortest_path
1186 ///Function type interface for Dijkstra algorithm.
1188 ///This function also has several
1189 ///\ref named-templ-func-param "named parameters",
1190 ///they are declared as the members of class \ref DijkstraWizard.
1192 ///example shows how to use these parameters.
1194 /// dijkstra(g,length,source).predMap(preds).run();
1196 ///\warning Don't forget to put the \ref DijkstraWizard::run() "run()"
1197 ///to the end of the parameter list.
1198 ///\sa DijkstraWizard
1200 template<class GR, class LM>
1201 DijkstraWizard<DijkstraWizardBase<GR,LM> >
1202 dijkstra(const GR &g,const LM &l,typename GR::Node s=INVALID)
1204 return DijkstraWizard<DijkstraWizardBase<GR,LM> >(g,l,s);
1207 } //END OF NAMESPACE LEMON