COIN-OR::LEMON - Graph Library

source: lemon-1.2/lemon/dijkstra.h @ 636:6dc44006c1a8

Last change on this file since 636:6dc44006c1a8 was 584:33c6b6e755cd, checked in by Peter Kovacs <kpeter@…>, 15 years ago

Small doc improvements (#263)

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[209]1/* -*- mode: C++; indent-tabs-mode: nil; -*-
[100]2 *
[209]3 * This file is a part of LEMON, a generic C++ optimization library.
[100]4 *
[440]5 * Copyright (C) 2003-2009
[100]6 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 *
9 * Permission to use, modify and distribute this software is granted
10 * provided that this copyright notice appears in all copies. For
11 * precise terms see the accompanying LICENSE file.
12 *
13 * This software is provided "AS IS" with no warranty of any kind,
14 * express or implied, and with no claim as to its suitability for any
15 * purpose.
16 *
17 */
18
19#ifndef LEMON_DIJKSTRA_H
20#define LEMON_DIJKSTRA_H
21
22///\ingroup shortest_path
23///\file
24///\brief Dijkstra algorithm.
25
[184]26#include <limits>
[169]27#include <lemon/list_graph.h>
[100]28#include <lemon/bin_heap.h>
29#include <lemon/bits/path_dump.h>
[220]30#include <lemon/core.h>
[100]31#include <lemon/error.h>
32#include <lemon/maps.h>
[278]33#include <lemon/path.h>
[100]34
35namespace lemon {
36
[244]37  /// \brief Default operation traits for the Dijkstra algorithm class.
[209]38  ///
[244]39  /// This operation traits class defines all computational operations and
40  /// constants which are used in the Dijkstra algorithm.
[559]41  template <typename V>
[100]42  struct DijkstraDefaultOperationTraits {
[559]43    /// \e
44    typedef V Value;
[100]45    /// \brief Gives back the zero value of the type.
46    static Value zero() {
47      return static_cast<Value>(0);
48    }
49    /// \brief Gives back the sum of the given two elements.
50    static Value plus(const Value& left, const Value& right) {
51      return left + right;
52    }
[244]53    /// \brief Gives back true only if the first value is less than the second.
[100]54    static bool less(const Value& left, const Value& right) {
55      return left < right;
56    }
57  };
58
59  ///Default traits class of Dijkstra class.
60
61  ///Default traits class of Dijkstra class.
[244]62  ///\tparam GR The type of the digraph.
[559]63  ///\tparam LEN The type of the length map.
64  template<typename GR, typename LEN>
[100]65  struct DijkstraDefaultTraits
66  {
[244]67    ///The type of the digraph the algorithm runs on.
[100]68    typedef GR Digraph;
[244]69
[100]70    ///The type of the map that stores the arc lengths.
71
72    ///The type of the map that stores the arc lengths.
73    ///It must meet the \ref concepts::ReadMap "ReadMap" concept.
[559]74    typedef LEN LengthMap;
[244]75    ///The type of the length of the arcs.
[559]76    typedef typename LEN::Value Value;
[244]77
[492]78    /// Operation traits for %Dijkstra algorithm.
[100]79
[244]80    /// This class defines the operations that are used in the algorithm.
[100]81    /// \see DijkstraDefaultOperationTraits
82    typedef DijkstraDefaultOperationTraits<Value> OperationTraits;
83
[244]84    /// The cross reference type used by the heap.
[100]85
[244]86    /// The cross reference type used by the heap.
[100]87    /// Usually it is \c Digraph::NodeMap<int>.
88    typedef typename Digraph::template NodeMap<int> HeapCrossRef;
[492]89    ///Instantiates a \c HeapCrossRef.
[100]90
[244]91    ///This function instantiates a \ref HeapCrossRef.
92    /// \param g is the digraph, to which we would like to define the
93    /// \ref HeapCrossRef.
94    static HeapCrossRef *createHeapCrossRef(const Digraph &g)
[100]95    {
[244]96      return new HeapCrossRef(g);
[100]97    }
[209]98
[492]99    ///The heap type used by the %Dijkstra algorithm.
[100]100
[244]101    ///The heap type used by the Dijkstra algorithm.
[100]102    ///
103    ///\sa BinHeap
104    ///\sa Dijkstra
[559]105    typedef BinHeap<typename LEN::Value, HeapCrossRef, std::less<Value> > Heap;
[492]106    ///Instantiates a \c Heap.
[100]107
[244]108    ///This function instantiates a \ref Heap.
109    static Heap *createHeap(HeapCrossRef& r)
[100]110    {
[244]111      return new Heap(r);
[100]112    }
113
[244]114    ///\brief The type of the map that stores the predecessor
[100]115    ///arcs of the shortest paths.
[209]116    ///
[244]117    ///The type of the map that stores the predecessor
[100]118    ///arcs of the shortest paths.
119    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
[244]120    typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
[492]121    ///Instantiates a \c PredMap.
[209]122
[492]123    ///This function instantiates a \ref PredMap.
[244]124    ///\param g is the digraph, to which we would like to define the
[492]125    ///\ref PredMap.
[244]126    static PredMap *createPredMap(const Digraph &g)
[100]127    {
[244]128      return new PredMap(g);
[100]129    }
130
[244]131    ///The type of the map that indicates which nodes are processed.
[209]132
[244]133    ///The type of the map that indicates which nodes are processed.
[100]134    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
135    ///By default it is a NullMap.
136    typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
[492]137    ///Instantiates a \c ProcessedMap.
[209]138
[492]139    ///This function instantiates a \ref ProcessedMap.
[100]140    ///\param g is the digraph, to which
[492]141    ///we would like to define the \ref ProcessedMap.
[100]142#ifdef DOXYGEN
[244]143    static ProcessedMap *createProcessedMap(const Digraph &g)
[100]144#else
[244]145    static ProcessedMap *createProcessedMap(const Digraph &)
[100]146#endif
147    {
148      return new ProcessedMap();
149    }
[209]150
[244]151    ///The type of the map that stores the distances of the nodes.
152
153    ///The type of the map that stores the distances of the nodes.
[100]154    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
[559]155    typedef typename Digraph::template NodeMap<typename LEN::Value> DistMap;
[492]156    ///Instantiates a \c DistMap.
[209]157
[492]158    ///This function instantiates a \ref DistMap.
[244]159    ///\param g is the digraph, to which we would like to define
[492]160    ///the \ref DistMap.
[244]161    static DistMap *createDistMap(const Digraph &g)
[100]162    {
[244]163      return new DistMap(g);
[100]164    }
165  };
[209]166
[100]167  ///%Dijkstra algorithm class.
[209]168
[100]169  /// \ingroup shortest_path
[244]170  ///This class provides an efficient implementation of the %Dijkstra algorithm.
171  ///
[100]172  ///The arc lengths are passed to the algorithm using a
173  ///\ref concepts::ReadMap "ReadMap",
174  ///so it is easy to change it to any kind of length.
175  ///The type of the length is determined by the
176  ///\ref concepts::ReadMap::Value "Value" of the length map.
177  ///It is also possible to change the underlying priority heap.
178  ///
[278]179  ///There is also a \ref dijkstra() "function-type interface" for the
[244]180  ///%Dijkstra algorithm, which is convenient in the simplier cases and
181  ///it can be used easier.
182  ///
183  ///\tparam GR The type of the digraph the algorithm runs on.
[405]184  ///The default type is \ref ListDigraph.
[559]185  ///\tparam LEN A \ref concepts::ReadMap "readable" arc map that specifies
[405]186  ///the lengths of the arcs.
187  ///It is read once for each arc, so the map may involve in
[244]188  ///relatively time consuming process to compute the arc lengths if
[100]189  ///it is necessary. The default map type is \ref
[405]190  ///concepts::Digraph::ArcMap "GR::ArcMap<int>".
[100]191#ifdef DOXYGEN
[559]192  template <typename GR, typename LEN, typename TR>
[100]193#else
194  template <typename GR=ListDigraph,
[559]195            typename LEN=typename GR::template ArcMap<int>,
196            typename TR=DijkstraDefaultTraits<GR,LEN> >
[100]197#endif
198  class Dijkstra {
199  public:
200
[244]201    ///The type of the digraph the algorithm runs on.
[100]202    typedef typename TR::Digraph Digraph;
[209]203
[100]204    ///The type of the length of the arcs.
205    typedef typename TR::LengthMap::Value Value;
206    ///The type of the map that stores the arc lengths.
207    typedef typename TR::LengthMap LengthMap;
[244]208    ///\brief The type of the map that stores the predecessor arcs of the
209    ///shortest paths.
[100]210    typedef typename TR::PredMap PredMap;
[244]211    ///The type of the map that stores the distances of the nodes.
212    typedef typename TR::DistMap DistMap;
213    ///The type of the map that indicates which nodes are processed.
[100]214    typedef typename TR::ProcessedMap ProcessedMap;
[244]215    ///The type of the paths.
216    typedef PredMapPath<Digraph, PredMap> Path;
[100]217    ///The cross reference type used for the current heap.
218    typedef typename TR::HeapCrossRef HeapCrossRef;
[244]219    ///The heap type used by the algorithm.
[100]220    typedef typename TR::Heap Heap;
[492]221    ///\brief The \ref DijkstraDefaultOperationTraits "operation traits class"
222    ///of the algorithm.
[100]223    typedef typename TR::OperationTraits OperationTraits;
[244]224
[405]225    ///The \ref DijkstraDefaultTraits "traits class" of the algorithm.
[244]226    typedef TR Traits;
227
[100]228  private:
[244]229
230    typedef typename Digraph::Node Node;
231    typedef typename Digraph::NodeIt NodeIt;
232    typedef typename Digraph::Arc Arc;
233    typedef typename Digraph::OutArcIt OutArcIt;
234
235    //Pointer to the underlying digraph.
[100]236    const Digraph *G;
[244]237    //Pointer to the length map.
[492]238    const LengthMap *_length;
[244]239    //Pointer to the map of predecessors arcs.
[100]240    PredMap *_pred;
[244]241    //Indicates if _pred is locally allocated (true) or not.
[100]242    bool local_pred;
[244]243    //Pointer to the map of distances.
[100]244    DistMap *_dist;
[244]245    //Indicates if _dist is locally allocated (true) or not.
[100]246    bool local_dist;
[244]247    //Pointer to the map of processed status of the nodes.
[100]248    ProcessedMap *_processed;
[244]249    //Indicates if _processed is locally allocated (true) or not.
[100]250    bool local_processed;
[244]251    //Pointer to the heap cross references.
[100]252    HeapCrossRef *_heap_cross_ref;
[244]253    //Indicates if _heap_cross_ref is locally allocated (true) or not.
[100]254    bool local_heap_cross_ref;
[244]255    //Pointer to the heap.
[100]256    Heap *_heap;
[244]257    //Indicates if _heap is locally allocated (true) or not.
[100]258    bool local_heap;
259
[280]260    //Creates the maps if necessary.
[209]261    void create_maps()
[100]262    {
263      if(!_pred) {
[209]264        local_pred = true;
265        _pred = Traits::createPredMap(*G);
[100]266      }
267      if(!_dist) {
[209]268        local_dist = true;
269        _dist = Traits::createDistMap(*G);
[100]270      }
271      if(!_processed) {
[209]272        local_processed = true;
273        _processed = Traits::createProcessedMap(*G);
[100]274      }
275      if (!_heap_cross_ref) {
[209]276        local_heap_cross_ref = true;
277        _heap_cross_ref = Traits::createHeapCrossRef(*G);
[100]278      }
279      if (!_heap) {
[209]280        local_heap = true;
281        _heap = Traits::createHeap(*_heap_cross_ref);
[100]282      }
283    }
[209]284
[244]285  public:
[100]286
287    typedef Dijkstra Create;
[209]288
[584]289    ///\name Named Template Parameters
[100]290
291    ///@{
292
293    template <class T>
[257]294    struct SetPredMapTraits : public Traits {
[100]295      typedef T PredMap;
296      static PredMap *createPredMap(const Digraph &)
297      {
[290]298        LEMON_ASSERT(false, "PredMap is not initialized");
299        return 0; // ignore warnings
[100]300      }
301    };
[244]302    ///\brief \ref named-templ-param "Named parameter" for setting
[492]303    ///\c PredMap type.
[100]304    ///
[244]305    ///\ref named-templ-param "Named parameter" for setting
[492]306    ///\c PredMap type.
[405]307    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
[100]308    template <class T>
[257]309    struct SetPredMap
310      : public Dijkstra< Digraph, LengthMap, SetPredMapTraits<T> > {
311      typedef Dijkstra< Digraph, LengthMap, SetPredMapTraits<T> > Create;
[100]312    };
[209]313
[100]314    template <class T>
[257]315    struct SetDistMapTraits : public Traits {
[100]316      typedef T DistMap;
317      static DistMap *createDistMap(const Digraph &)
318      {
[290]319        LEMON_ASSERT(false, "DistMap is not initialized");
320        return 0; // ignore warnings
[100]321      }
322    };
[244]323    ///\brief \ref named-templ-param "Named parameter" for setting
[492]324    ///\c DistMap type.
[100]325    ///
[244]326    ///\ref named-templ-param "Named parameter" for setting
[492]327    ///\c DistMap type.
[405]328    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
[100]329    template <class T>
[257]330    struct SetDistMap
331      : public Dijkstra< Digraph, LengthMap, SetDistMapTraits<T> > {
332      typedef Dijkstra< Digraph, LengthMap, SetDistMapTraits<T> > Create;
[100]333    };
[209]334
[100]335    template <class T>
[257]336    struct SetProcessedMapTraits : public Traits {
[100]337      typedef T ProcessedMap;
[244]338      static ProcessedMap *createProcessedMap(const Digraph &)
[100]339      {
[290]340        LEMON_ASSERT(false, "ProcessedMap is not initialized");
341        return 0; // ignore warnings
[100]342      }
343    };
[244]344    ///\brief \ref named-templ-param "Named parameter" for setting
[492]345    ///\c ProcessedMap type.
[100]346    ///
[244]347    ///\ref named-templ-param "Named parameter" for setting
[492]348    ///\c ProcessedMap type.
[405]349    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
[100]350    template <class T>
[257]351    struct SetProcessedMap
352      : public Dijkstra< Digraph, LengthMap, SetProcessedMapTraits<T> > {
353      typedef Dijkstra< Digraph, LengthMap, SetProcessedMapTraits<T> > Create;
[100]354    };
[209]355
[257]356    struct SetStandardProcessedMapTraits : public Traits {
[100]357      typedef typename Digraph::template NodeMap<bool> ProcessedMap;
[244]358      static ProcessedMap *createProcessedMap(const Digraph &g)
[100]359      {
[244]360        return new ProcessedMap(g);
[100]361      }
362    };
[244]363    ///\brief \ref named-templ-param "Named parameter" for setting
[492]364    ///\c ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
[100]365    ///
[244]366    ///\ref named-templ-param "Named parameter" for setting
[492]367    ///\c ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
[244]368    ///If you don't set it explicitly, it will be automatically allocated.
[257]369    struct SetStandardProcessedMap
370      : public Dijkstra< Digraph, LengthMap, SetStandardProcessedMapTraits > {
371      typedef Dijkstra< Digraph, LengthMap, SetStandardProcessedMapTraits >
[210]372      Create;
[100]373    };
374
375    template <class H, class CR>
[257]376    struct SetHeapTraits : public Traits {
[100]377      typedef CR HeapCrossRef;
378      typedef H Heap;
379      static HeapCrossRef *createHeapCrossRef(const Digraph &) {
[290]380        LEMON_ASSERT(false, "HeapCrossRef is not initialized");
381        return 0; // ignore warnings
[100]382      }
[209]383      static Heap *createHeap(HeapCrossRef &)
[100]384      {
[290]385        LEMON_ASSERT(false, "Heap is not initialized");
386        return 0; // ignore warnings
[100]387      }
388    };
389    ///\brief \ref named-templ-param "Named parameter" for setting
[405]390    ///heap and cross reference types
[100]391    ///
[209]392    ///\ref named-templ-param "Named parameter" for setting heap and cross
[405]393    ///reference types. If this named parameter is used, then external
394    ///heap and cross reference objects must be passed to the algorithm
395    ///using the \ref heap() function before calling \ref run(Node) "run()"
396    ///or \ref init().
397    ///\sa SetStandardHeap
[100]398    template <class H, class CR = typename Digraph::template NodeMap<int> >
[257]399    struct SetHeap
400      : public Dijkstra< Digraph, LengthMap, SetHeapTraits<H, CR> > {
401      typedef Dijkstra< Digraph, LengthMap, SetHeapTraits<H, CR> > Create;
[100]402    };
403
404    template <class H, class CR>
[257]405    struct SetStandardHeapTraits : public Traits {
[100]406      typedef CR HeapCrossRef;
407      typedef H Heap;
408      static HeapCrossRef *createHeapCrossRef(const Digraph &G) {
[209]409        return new HeapCrossRef(G);
[100]410      }
[209]411      static Heap *createHeap(HeapCrossRef &R)
[100]412      {
[209]413        return new Heap(R);
[100]414      }
415    };
416    ///\brief \ref named-templ-param "Named parameter" for setting
[405]417    ///heap and cross reference types with automatic allocation
[100]418    ///
[209]419    ///\ref named-templ-param "Named parameter" for setting heap and cross
[405]420    ///reference types with automatic allocation.
421    ///They should have standard constructor interfaces to be able to
422    ///automatically created by the algorithm (i.e. the digraph should be
423    ///passed to the constructor of the cross reference and the cross
424    ///reference should be passed to the constructor of the heap).
425    ///However external heap and cross reference objects could also be
426    ///passed to the algorithm using the \ref heap() function before
427    ///calling \ref run(Node) "run()" or \ref init().
428    ///\sa SetHeap
[100]429    template <class H, class CR = typename Digraph::template NodeMap<int> >
[257]430    struct SetStandardHeap
431      : public Dijkstra< Digraph, LengthMap, SetStandardHeapTraits<H, CR> > {
432      typedef Dijkstra< Digraph, LengthMap, SetStandardHeapTraits<H, CR> >
[100]433      Create;
434    };
435
436    template <class T>
[257]437    struct SetOperationTraitsTraits : public Traits {
[100]438      typedef T OperationTraits;
439    };
[209]440
441    /// \brief \ref named-templ-param "Named parameter" for setting
[313]442    ///\c OperationTraits type
[100]443    ///
[244]444    ///\ref named-templ-param "Named parameter" for setting
[492]445    ///\c OperationTraits type.
[100]446    template <class T>
[257]447    struct SetOperationTraits
448      : public Dijkstra<Digraph, LengthMap, SetOperationTraitsTraits<T> > {
449      typedef Dijkstra<Digraph, LengthMap, SetOperationTraitsTraits<T> >
[100]450      Create;
451    };
[209]452
[100]453    ///@}
454
455  protected:
456
457    Dijkstra() {}
458
[209]459  public:
460
[100]461    ///Constructor.
[209]462
[244]463    ///Constructor.
[492]464    ///\param g The digraph the algorithm runs on.
465    ///\param length The length map used by the algorithm.
466    Dijkstra(const Digraph& g, const LengthMap& length) :
467      G(&g), _length(&length),
[100]468      _pred(NULL), local_pred(false),
469      _dist(NULL), local_dist(false),
470      _processed(NULL), local_processed(false),
471      _heap_cross_ref(NULL), local_heap_cross_ref(false),
472      _heap(NULL), local_heap(false)
473    { }
[209]474
[100]475    ///Destructor.
[209]476    ~Dijkstra()
[100]477    {
478      if(local_pred) delete _pred;
479      if(local_dist) delete _dist;
480      if(local_processed) delete _processed;
481      if(local_heap_cross_ref) delete _heap_cross_ref;
482      if(local_heap) delete _heap;
483    }
484
485    ///Sets the length map.
486
487    ///Sets the length map.
488    ///\return <tt> (*this) </tt>
[209]489    Dijkstra &lengthMap(const LengthMap &m)
[100]490    {
[492]491      _length = &m;
[100]492      return *this;
493    }
494
[244]495    ///Sets the map that stores the predecessor arcs.
[100]496
[244]497    ///Sets the map that stores the predecessor arcs.
[405]498    ///If you don't use this function before calling \ref run(Node) "run()"
499    ///or \ref init(), an instance will be allocated automatically.
500    ///The destructor deallocates this automatically allocated map,
501    ///of course.
[100]502    ///\return <tt> (*this) </tt>
[209]503    Dijkstra &predMap(PredMap &m)
[100]504    {
505      if(local_pred) {
[209]506        delete _pred;
507        local_pred=false;
[100]508      }
509      _pred = &m;
510      return *this;
511    }
512
[244]513    ///Sets the map that indicates which nodes are processed.
[100]514
[244]515    ///Sets the map that indicates which nodes are processed.
[405]516    ///If you don't use this function before calling \ref run(Node) "run()"
517    ///or \ref init(), an instance will be allocated automatically.
518    ///The destructor deallocates this automatically allocated map,
519    ///of course.
[244]520    ///\return <tt> (*this) </tt>
521    Dijkstra &processedMap(ProcessedMap &m)
522    {
523      if(local_processed) {
524        delete _processed;
525        local_processed=false;
526      }
527      _processed = &m;
528      return *this;
529    }
530
531    ///Sets the map that stores the distances of the nodes.
532
533    ///Sets the map that stores the distances of the nodes calculated by the
534    ///algorithm.
[405]535    ///If you don't use this function before calling \ref run(Node) "run()"
536    ///or \ref init(), an instance will be allocated automatically.
537    ///The destructor deallocates this automatically allocated map,
538    ///of course.
[100]539    ///\return <tt> (*this) </tt>
[209]540    Dijkstra &distMap(DistMap &m)
[100]541    {
542      if(local_dist) {
[209]543        delete _dist;
544        local_dist=false;
[100]545      }
546      _dist = &m;
547      return *this;
548    }
549
550    ///Sets the heap and the cross reference used by algorithm.
551
552    ///Sets the heap and the cross reference used by algorithm.
[405]553    ///If you don't use this function before calling \ref run(Node) "run()"
554    ///or \ref init(), heap and cross reference instances will be
555    ///allocated automatically.
556    ///The destructor deallocates these automatically allocated objects,
557    ///of course.
[100]558    ///\return <tt> (*this) </tt>
559    Dijkstra &heap(Heap& hp, HeapCrossRef &cr)
560    {
561      if(local_heap_cross_ref) {
[209]562        delete _heap_cross_ref;
563        local_heap_cross_ref=false;
[100]564      }
565      _heap_cross_ref = &cr;
566      if(local_heap) {
[209]567        delete _heap;
568        local_heap=false;
[100]569      }
570      _heap = &hp;
571      return *this;
572    }
573
574  private:
[244]575
[100]576    void finalizeNodeData(Node v,Value dst)
577    {
578      _processed->set(v,true);
579      _dist->set(v, dst);
580    }
581
582  public:
583
[405]584    ///\name Execution Control
585    ///The simplest way to execute the %Dijkstra algorithm is to use
586    ///one of the member functions called \ref run(Node) "run()".\n
587    ///If you need more control on the execution, first you have to call
588    ///\ref init(), then you can add several source nodes with
589    ///\ref addSource(). Finally the actual path computation can be
590    ///performed with one of the \ref start() functions.
[100]591
592    ///@{
593
[405]594    ///\brief Initializes the internal data structures.
595    ///
[100]596    ///Initializes the internal data structures.
597    void init()
598    {
599      create_maps();
600      _heap->clear();
601      for ( NodeIt u(*G) ; u!=INVALID ; ++u ) {
[209]602        _pred->set(u,INVALID);
603        _processed->set(u,false);
604        _heap_cross_ref->set(u,Heap::PRE_HEAP);
[100]605      }
606    }
[209]607
[100]608    ///Adds a new source node.
609
610    ///Adds a new source node to the priority heap.
611    ///The optional second parameter is the initial distance of the node.
612    ///
[244]613    ///The function checks if the node has already been added to the heap and
[100]614    ///it is pushed to the heap only if either it was not in the heap
615    ///or the shortest path found till then is shorter than \c dst.
616    void addSource(Node s,Value dst=OperationTraits::zero())
617    {
618      if(_heap->state(s) != Heap::IN_HEAP) {
[209]619        _heap->push(s,dst);
[100]620      } else if(OperationTraits::less((*_heap)[s], dst)) {
[209]621        _heap->set(s,dst);
622        _pred->set(s,INVALID);
[100]623      }
624    }
[209]625
[100]626    ///Processes the next node in the priority heap
627
628    ///Processes the next node in the priority heap.
629    ///
630    ///\return The processed node.
631    ///
[244]632    ///\warning The priority heap must not be empty.
[100]633    Node processNextNode()
634    {
[209]635      Node v=_heap->top();
[100]636      Value oldvalue=_heap->prio();
637      _heap->pop();
638      finalizeNodeData(v,oldvalue);
[209]639
[100]640      for(OutArcIt e(*G,v); e!=INVALID; ++e) {
[209]641        Node w=G->target(e);
642        switch(_heap->state(w)) {
643        case Heap::PRE_HEAP:
[492]644          _heap->push(w,OperationTraits::plus(oldvalue, (*_length)[e]));
[209]645          _pred->set(w,e);
646          break;
647        case Heap::IN_HEAP:
648          {
[492]649            Value newvalue = OperationTraits::plus(oldvalue, (*_length)[e]);
[209]650            if ( OperationTraits::less(newvalue, (*_heap)[w]) ) {
651              _heap->decrease(w, newvalue);
652              _pred->set(w,e);
653            }
654          }
655          break;
656        case Heap::POST_HEAP:
657          break;
658        }
[100]659      }
660      return v;
661    }
662
[244]663    ///The next node to be processed.
[209]664
[244]665    ///Returns the next node to be processed or \c INVALID if the
666    ///priority heap is empty.
667    Node nextNode() const
[209]668    {
[100]669      return !_heap->empty()?_heap->top():INVALID;
670    }
[209]671
[405]672    ///Returns \c false if there are nodes to be processed.
673
674    ///Returns \c false if there are nodes to be processed
675    ///in the priority heap.
[244]676    bool emptyQueue() const { return _heap->empty(); }
677
[405]678    ///Returns the number of the nodes to be processed.
[100]679
[405]680    ///Returns the number of the nodes to be processed
681    ///in the priority heap.
[244]682    int queueSize() const { return _heap->size(); }
[209]683
[100]684    ///Executes the algorithm.
685
686    ///Executes the algorithm.
687    ///
[244]688    ///This method runs the %Dijkstra algorithm from the root node(s)
689    ///in order to compute the shortest path to each node.
690    ///
691    ///The algorithm computes
692    ///- the shortest path tree (forest),
693    ///- the distance of each node from the root(s).
694    ///
695    ///\pre init() must be called and at least one root node should be
696    ///added with addSource() before using this function.
697    ///
698    ///\note <tt>d.start()</tt> is just a shortcut of the following code.
699    ///\code
700    ///  while ( !d.emptyQueue() ) {
701    ///    d.processNextNode();
702    ///  }
703    ///\endcode
704    void start()
705    {
706      while ( !emptyQueue() ) processNextNode();
707    }
708
[286]709    ///Executes the algorithm until the given target node is processed.
[244]710
[286]711    ///Executes the algorithm until the given target node is processed.
[100]712    ///
713    ///This method runs the %Dijkstra algorithm from the root node(s)
[286]714    ///in order to compute the shortest path to \c t.
[100]715    ///
[244]716    ///The algorithm computes
[286]717    ///- the shortest path to \c t,
718    ///- the distance of \c t from the root(s).
[100]719    ///
[244]720    ///\pre init() must be called and at least one root node should be
721    ///added with addSource() before using this function.
[286]722    void start(Node t)
[100]723    {
[286]724      while ( !_heap->empty() && _heap->top()!=t ) processNextNode();
725      if ( !_heap->empty() ) {
726        finalizeNodeData(_heap->top(),_heap->prio());
727        _heap->pop();
728      }
[100]729    }
[209]730
[100]731    ///Executes the algorithm until a condition is met.
732
733    ///Executes the algorithm until a condition is met.
734    ///
[244]735    ///This method runs the %Dijkstra algorithm from the root node(s) in
736    ///order to compute the shortest path to a node \c v with
737    /// <tt>nm[v]</tt> true, if such a node can be found.
[100]738    ///
[244]739    ///\param nm A \c bool (or convertible) node map. The algorithm
[100]740    ///will stop when it reaches a node \c v with <tt>nm[v]</tt> true.
741    ///
742    ///\return The reached node \c v with <tt>nm[v]</tt> true or
743    ///\c INVALID if no such node was found.
[244]744    ///
745    ///\pre init() must be called and at least one root node should be
746    ///added with addSource() before using this function.
[100]747    template<class NodeBoolMap>
748    Node start(const NodeBoolMap &nm)
749    {
750      while ( !_heap->empty() && !nm[_heap->top()] ) processNextNode();
751      if ( _heap->empty() ) return INVALID;
752      finalizeNodeData(_heap->top(),_heap->prio());
753      return _heap->top();
754    }
[209]755
[286]756    ///Runs the algorithm from the given source node.
[209]757
[244]758    ///This method runs the %Dijkstra algorithm from node \c s
759    ///in order to compute the shortest path to each node.
[100]760    ///
[244]761    ///The algorithm computes
762    ///- the shortest path tree,
763    ///- the distance of each node from the root.
764    ///
765    ///\note <tt>d.run(s)</tt> is just a shortcut of the following code.
[100]766    ///\code
767    ///  d.init();
768    ///  d.addSource(s);
769    ///  d.start();
770    ///\endcode
771    void run(Node s) {
772      init();
773      addSource(s);
774      start();
775    }
[209]776
[100]777    ///Finds the shortest path between \c s and \c t.
[209]778
[244]779    ///This method runs the %Dijkstra algorithm from node \c s
[286]780    ///in order to compute the shortest path to node \c t
781    ///(it stops searching when \c t is processed).
[100]782    ///
[286]783    ///\return \c true if \c t is reachable form \c s.
[244]784    ///
785    ///\note Apart from the return value, <tt>d.run(s,t)</tt> is just a
786    ///shortcut of the following code.
[100]787    ///\code
788    ///  d.init();
789    ///  d.addSource(s);
790    ///  d.start(t);
791    ///\endcode
[286]792    bool run(Node s,Node t) {
[100]793      init();
794      addSource(s);
795      start(t);
[286]796      return (*_heap_cross_ref)[t] == Heap::POST_HEAP;
[100]797    }
[209]798
[100]799    ///@}
800
801    ///\name Query Functions
[405]802    ///The results of the %Dijkstra algorithm can be obtained using these
[100]803    ///functions.\n
[405]804    ///Either \ref run(Node) "run()" or \ref start() should be called
805    ///before using them.
[209]806
[100]807    ///@{
808
[244]809    ///The shortest path to a node.
[209]810
[244]811    ///Returns the shortest path to a node.
812    ///
[405]813    ///\warning \c t should be reached from the root(s).
[244]814    ///
[405]815    ///\pre Either \ref run(Node) "run()" or \ref init()
816    ///must be called before using this function.
[244]817    Path path(Node t) const { return Path(*G, *_pred, t); }
[100]818
[244]819    ///The distance of a node from the root(s).
[100]820
[244]821    ///Returns the distance of a node from the root(s).
822    ///
[405]823    ///\warning If node \c v is not reached from the root(s), then
[244]824    ///the return value of this function is undefined.
825    ///
[405]826    ///\pre Either \ref run(Node) "run()" or \ref init()
827    ///must be called before using this function.
[100]828    Value dist(Node v) const { return (*_dist)[v]; }
829
[244]830    ///Returns the 'previous arc' of the shortest path tree for a node.
[100]831
[244]832    ///This function returns the 'previous arc' of the shortest path
833    ///tree for the node \c v, i.e. it returns the last arc of a
[405]834    ///shortest path from a root to \c v. It is \c INVALID if \c v
835    ///is not reached from the root(s) or if \c v is a root.
[244]836    ///
837    ///The shortest path tree used here is equal to the shortest path
838    ///tree used in \ref predNode().
839    ///
[405]840    ///\pre Either \ref run(Node) "run()" or \ref init()
841    ///must be called before using this function.
[100]842    Arc predArc(Node v) const { return (*_pred)[v]; }
843
[244]844    ///Returns the 'previous node' of the shortest path tree for a node.
[100]845
[244]846    ///This function returns the 'previous node' of the shortest path
847    ///tree for the node \c v, i.e. it returns the last but one node
[405]848    ///from a shortest path from a root to \c v. It is \c INVALID
849    ///if \c v is not reached from the root(s) or if \c v is a root.
[244]850    ///
851    ///The shortest path tree used here is equal to the shortest path
852    ///tree used in \ref predArc().
853    ///
[405]854    ///\pre Either \ref run(Node) "run()" or \ref init()
855    ///must be called before using this function.
[100]856    Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID:
[209]857                                  G->source((*_pred)[v]); }
858
[244]859    ///\brief Returns a const reference to the node map that stores the
860    ///distances of the nodes.
861    ///
862    ///Returns a const reference to the node map that stores the distances
863    ///of the nodes calculated by the algorithm.
864    ///
[405]865    ///\pre Either \ref run(Node) "run()" or \ref init()
[244]866    ///must be called before using this function.
[100]867    const DistMap &distMap() const { return *_dist;}
[209]868
[244]869    ///\brief Returns a const reference to the node map that stores the
870    ///predecessor arcs.
871    ///
872    ///Returns a const reference to the node map that stores the predecessor
873    ///arcs, which form the shortest path tree.
874    ///
[405]875    ///\pre Either \ref run(Node) "run()" or \ref init()
[244]876    ///must be called before using this function.
[100]877    const PredMap &predMap() const { return *_pred;}
[209]878
[405]879    ///Checks if a node is reached from the root(s).
[100]880
[405]881    ///Returns \c true if \c v is reached from the root(s).
882    ///
883    ///\pre Either \ref run(Node) "run()" or \ref init()
[244]884    ///must be called before using this function.
885    bool reached(Node v) const { return (*_heap_cross_ref)[v] !=
886                                        Heap::PRE_HEAP; }
[100]887
888    ///Checks if a node is processed.
889
890    ///Returns \c true if \c v is processed, i.e. the shortest
891    ///path to \c v has already found.
[405]892    ///
893    ///\pre Either \ref run(Node) "run()" or \ref init()
[244]894    ///must be called before using this function.
895    bool processed(Node v) const { return (*_heap_cross_ref)[v] ==
896                                          Heap::POST_HEAP; }
897
898    ///The current distance of a node from the root(s).
899
900    ///Returns the current distance of a node from the root(s).
901    ///It may be decreased in the following processes.
[405]902    ///
903    ///\pre Either \ref run(Node) "run()" or \ref init()
[286]904    ///must be called before using this function and
905    ///node \c v must be reached but not necessarily processed.
906    Value currentDist(Node v) const {
907      return processed(v) ? (*_dist)[v] : (*_heap)[v];
908    }
[209]909
[100]910    ///@}
911  };
912
913
[244]914  ///Default traits class of dijkstra() function.
[100]915
[244]916  ///Default traits class of dijkstra() function.
917  ///\tparam GR The type of the digraph.
[559]918  ///\tparam LEN The type of the length map.
919  template<class GR, class LEN>
[100]920  struct DijkstraWizardDefaultTraits
921  {
[244]922    ///The type of the digraph the algorithm runs on.
[100]923    typedef GR Digraph;
924    ///The type of the map that stores the arc lengths.
925
926    ///The type of the map that stores the arc lengths.
927    ///It must meet the \ref concepts::ReadMap "ReadMap" concept.
[559]928    typedef LEN LengthMap;
[244]929    ///The type of the length of the arcs.
[559]930    typedef typename LEN::Value Value;
[244]931
[100]932    /// Operation traits for Dijkstra algorithm.
933
[244]934    /// This class defines the operations that are used in the algorithm.
[100]935    /// \see DijkstraDefaultOperationTraits
936    typedef DijkstraDefaultOperationTraits<Value> OperationTraits;
937
[244]938    /// The cross reference type used by the heap.
[100]939
[244]940    /// The cross reference type used by the heap.
[100]941    /// Usually it is \c Digraph::NodeMap<int>.
942    typedef typename Digraph::template NodeMap<int> HeapCrossRef;
[244]943    ///Instantiates a \ref HeapCrossRef.
[100]944
[209]945    ///This function instantiates a \ref HeapCrossRef.
[244]946    /// \param g is the digraph, to which we would like to define the
[100]947    /// HeapCrossRef.
[244]948    static HeapCrossRef *createHeapCrossRef(const Digraph &g)
[100]949    {
[244]950      return new HeapCrossRef(g);
[100]951    }
[209]952
[244]953    ///The heap type used by the Dijkstra algorithm.
[100]954
[244]955    ///The heap type used by the Dijkstra algorithm.
[100]956    ///
957    ///\sa BinHeap
958    ///\sa Dijkstra
[244]959    typedef BinHeap<Value, typename Digraph::template NodeMap<int>,
[209]960                    std::less<Value> > Heap;
[100]961
[244]962    ///Instantiates a \ref Heap.
963
964    ///This function instantiates a \ref Heap.
965    /// \param r is the HeapCrossRef which is used.
966    static Heap *createHeap(HeapCrossRef& r)
[100]967    {
[244]968      return new Heap(r);
[100]969    }
970
[244]971    ///\brief The type of the map that stores the predecessor
[100]972    ///arcs of the shortest paths.
[209]973    ///
[244]974    ///The type of the map that stores the predecessor
[100]975    ///arcs of the shortest paths.
976    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
[278]977    typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
[301]978    ///Instantiates a PredMap.
[209]979
[301]980    ///This function instantiates a PredMap.
[244]981    ///\param g is the digraph, to which we would like to define the
[301]982    ///PredMap.
[244]983    static PredMap *createPredMap(const Digraph &g)
[100]984    {
[278]985      return new PredMap(g);
[100]986    }
[209]987
[244]988    ///The type of the map that indicates which nodes are processed.
989
990    ///The type of the map that indicates which nodes are processed.
[100]991    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
992    ///By default it is a NullMap.
993    typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
[301]994    ///Instantiates a ProcessedMap.
[209]995
[301]996    ///This function instantiates a ProcessedMap.
[100]997    ///\param g is the digraph, to which
[301]998    ///we would like to define the ProcessedMap.
[100]999#ifdef DOXYGEN
[244]1000    static ProcessedMap *createProcessedMap(const Digraph &g)
[100]1001#else
[244]1002    static ProcessedMap *createProcessedMap(const Digraph &)
[100]1003#endif
1004    {
1005      return new ProcessedMap();
1006    }
[209]1007
[244]1008    ///The type of the map that stores the distances of the nodes.
1009
1010    ///The type of the map that stores the distances of the nodes.
[100]1011    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
[559]1012    typedef typename Digraph::template NodeMap<typename LEN::Value> DistMap;
[301]1013    ///Instantiates a DistMap.
[209]1014
[301]1015    ///This function instantiates a DistMap.
[210]1016    ///\param g is the digraph, to which we would like to define
[301]1017    ///the DistMap
[244]1018    static DistMap *createDistMap(const Digraph &g)
[100]1019    {
[278]1020      return new DistMap(g);
[100]1021    }
[278]1022
1023    ///The type of the shortest paths.
1024
1025    ///The type of the shortest paths.
1026    ///It must meet the \ref concepts::Path "Path" concept.
1027    typedef lemon::Path<Digraph> Path;
[100]1028  };
[209]1029
[313]1030  /// Default traits class used by DijkstraWizard
[100]1031
1032  /// To make it easier to use Dijkstra algorithm
[244]1033  /// we have created a wizard class.
[100]1034  /// This \ref DijkstraWizard class needs default traits,
[244]1035  /// as well as the \ref Dijkstra class.
[100]1036  /// The \ref DijkstraWizardBase is a class to be the default traits of the
1037  /// \ref DijkstraWizard class.
[559]1038  template<typename GR, typename LEN>
1039  class DijkstraWizardBase : public DijkstraWizardDefaultTraits<GR,LEN>
[100]1040  {
[559]1041    typedef DijkstraWizardDefaultTraits<GR,LEN> Base;
[100]1042  protected:
[244]1043    //The type of the nodes in the digraph.
[100]1044    typedef typename Base::Digraph::Node Node;
1045
[244]1046    //Pointer to the digraph the algorithm runs on.
[100]1047    void *_g;
[278]1048    //Pointer to the length map.
[100]1049    void *_length;
[251]1050    //Pointer to the map of processed nodes.
1051    void *_processed;
[244]1052    //Pointer to the map of predecessors arcs.
[100]1053    void *_pred;
[244]1054    //Pointer to the map of distances.
[100]1055    void *_dist;
[278]1056    //Pointer to the shortest path to the target node.
1057    void *_path;
1058    //Pointer to the distance of the target node.
1059    void *_di;
[100]1060
[244]1061  public:
[100]1062    /// Constructor.
[209]1063
[100]1064    /// This constructor does not require parameters, therefore it initiates
[278]1065    /// all of the attributes to \c 0.
[251]1066    DijkstraWizardBase() : _g(0), _length(0), _processed(0), _pred(0),
[278]1067                           _dist(0), _path(0), _di(0) {}
[100]1068
1069    /// Constructor.
[209]1070
[278]1071    /// This constructor requires two parameters,
1072    /// others are initiated to \c 0.
[244]1073    /// \param g The digraph the algorithm runs on.
1074    /// \param l The length map.
[559]1075    DijkstraWizardBase(const GR &g,const LEN &l) :
[209]1076      _g(reinterpret_cast<void*>(const_cast<GR*>(&g))),
[559]1077      _length(reinterpret_cast<void*>(const_cast<LEN*>(&l))),
[278]1078      _processed(0), _pred(0), _dist(0), _path(0), _di(0) {}
[100]1079
1080  };
[209]1081
[278]1082  /// Auxiliary class for the function-type interface of Dijkstra algorithm.
[100]1083
[278]1084  /// This auxiliary class is created to implement the
1085  /// \ref dijkstra() "function-type interface" of \ref Dijkstra algorithm.
[405]1086  /// It does not have own \ref run(Node) "run()" method, it uses the
1087  /// functions and features of the plain \ref Dijkstra.
[100]1088  ///
[278]1089  /// This class should only be used through the \ref dijkstra() function,
1090  /// which makes it easier to use the algorithm.
[100]1091  template<class TR>
1092  class DijkstraWizard : public TR
1093  {
1094    typedef TR Base;
1095
[244]1096    ///The type of the digraph the algorithm runs on.
[100]1097    typedef typename TR::Digraph Digraph;
[244]1098
[100]1099    typedef typename Digraph::Node Node;
1100    typedef typename Digraph::NodeIt NodeIt;
1101    typedef typename Digraph::Arc Arc;
1102    typedef typename Digraph::OutArcIt OutArcIt;
[209]1103
[100]1104    ///The type of the map that stores the arc lengths.
1105    typedef typename TR::LengthMap LengthMap;
1106    ///The type of the length of the arcs.
1107    typedef typename LengthMap::Value Value;
[244]1108    ///\brief The type of the map that stores the predecessor
[100]1109    ///arcs of the shortest paths.
1110    typedef typename TR::PredMap PredMap;
[244]1111    ///The type of the map that stores the distances of the nodes.
[100]1112    typedef typename TR::DistMap DistMap;
[244]1113    ///The type of the map that indicates which nodes are processed.
1114    typedef typename TR::ProcessedMap ProcessedMap;
[278]1115    ///The type of the shortest paths
1116    typedef typename TR::Path Path;
[100]1117    ///The heap type used by the dijkstra algorithm.
1118    typedef typename TR::Heap Heap;
[244]1119
[100]1120  public:
[244]1121
[100]1122    /// Constructor.
1123    DijkstraWizard() : TR() {}
1124
1125    /// Constructor that requires parameters.
1126
1127    /// Constructor that requires parameters.
1128    /// These parameters will be the default values for the traits class.
[278]1129    /// \param g The digraph the algorithm runs on.
1130    /// \param l The length map.
1131    DijkstraWizard(const Digraph &g, const LengthMap &l) :
1132      TR(g,l) {}
[100]1133
1134    ///Copy constructor
1135    DijkstraWizard(const TR &b) : TR(b) {}
1136
1137    ~DijkstraWizard() {}
1138
[278]1139    ///Runs Dijkstra algorithm from the given source node.
[209]1140
[278]1141    ///This method runs %Dijkstra algorithm from the given source node
1142    ///in order to compute the shortest path to each node.
1143    void run(Node s)
[100]1144    {
[209]1145      Dijkstra<Digraph,LengthMap,TR>
[278]1146        dijk(*reinterpret_cast<const Digraph*>(Base::_g),
1147             *reinterpret_cast<const LengthMap*>(Base::_length));
1148      if (Base::_pred)
1149        dijk.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
1150      if (Base::_dist)
1151        dijk.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
1152      if (Base::_processed)
1153        dijk.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
1154      dijk.run(s);
[100]1155    }
1156
[278]1157    ///Finds the shortest path between \c s and \c t.
[100]1158
[278]1159    ///This method runs the %Dijkstra algorithm from node \c s
1160    ///in order to compute the shortest path to node \c t
1161    ///(it stops searching when \c t is processed).
1162    ///
1163    ///\return \c true if \c t is reachable form \c s.
1164    bool run(Node s, Node t)
[100]1165    {
[278]1166      Dijkstra<Digraph,LengthMap,TR>
1167        dijk(*reinterpret_cast<const Digraph*>(Base::_g),
1168             *reinterpret_cast<const LengthMap*>(Base::_length));
1169      if (Base::_pred)
1170        dijk.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
1171      if (Base::_dist)
1172        dijk.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
1173      if (Base::_processed)
1174        dijk.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
1175      dijk.run(s,t);
1176      if (Base::_path)
1177        *reinterpret_cast<Path*>(Base::_path) = dijk.path(t);
1178      if (Base::_di)
1179        *reinterpret_cast<Value*>(Base::_di) = dijk.dist(t);
1180      return dijk.reached(t);
[244]1181    }
1182
[100]1183    template<class T>
[257]1184    struct SetPredMapBase : public Base {
[100]1185      typedef T PredMap;
1186      static PredMap *createPredMap(const Digraph &) { return 0; };
[257]1187      SetPredMapBase(const TR &b) : TR(b) {}
[100]1188    };
[278]1189    ///\brief \ref named-func-param "Named parameter"
[301]1190    ///for setting PredMap object.
[100]1191    ///
[278]1192    ///\ref named-func-param "Named parameter"
[301]1193    ///for setting PredMap object.
[100]1194    template<class T>
[257]1195    DijkstraWizard<SetPredMapBase<T> > predMap(const T &t)
[100]1196    {
1197      Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t));
[257]1198      return DijkstraWizard<SetPredMapBase<T> >(*this);
[100]1199    }
[209]1200
[100]1201    template<class T>
[278]1202    struct SetDistMapBase : public Base {
1203      typedef T DistMap;
1204      static DistMap *createDistMap(const Digraph &) { return 0; };
1205      SetDistMapBase(const TR &b) : TR(b) {}
1206    };
1207    ///\brief \ref named-func-param "Named parameter"
[301]1208    ///for setting DistMap object.
[278]1209    ///
1210    ///\ref named-func-param "Named parameter"
[301]1211    ///for setting DistMap object.
[278]1212    template<class T>
1213    DijkstraWizard<SetDistMapBase<T> > distMap(const T &t)
1214    {
1215      Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t));
1216      return DijkstraWizard<SetDistMapBase<T> >(*this);
1217    }
1218
1219    template<class T>
[257]1220    struct SetProcessedMapBase : public Base {
[244]1221      typedef T ProcessedMap;
1222      static ProcessedMap *createProcessedMap(const Digraph &) { return 0; };
[257]1223      SetProcessedMapBase(const TR &b) : TR(b) {}
[244]1224    };
[278]1225    ///\brief \ref named-func-param "Named parameter"
[301]1226    ///for setting ProcessedMap object.
[244]1227    ///
[278]1228    /// \ref named-func-param "Named parameter"
[301]1229    ///for setting ProcessedMap object.
[244]1230    template<class T>
[257]1231    DijkstraWizard<SetProcessedMapBase<T> > processedMap(const T &t)
[244]1232    {
1233      Base::_processed=reinterpret_cast<void*>(const_cast<T*>(&t));
[257]1234      return DijkstraWizard<SetProcessedMapBase<T> >(*this);
[244]1235    }
1236
1237    template<class T>
[278]1238    struct SetPathBase : public Base {
1239      typedef T Path;
1240      SetPathBase(const TR &b) : TR(b) {}
[100]1241    };
[278]1242    ///\brief \ref named-func-param "Named parameter"
1243    ///for getting the shortest path to the target node.
[100]1244    ///
[278]1245    ///\ref named-func-param "Named parameter"
1246    ///for getting the shortest path to the target node.
[100]1247    template<class T>
[278]1248    DijkstraWizard<SetPathBase<T> > path(const T &t)
[100]1249    {
[278]1250      Base::_path=reinterpret_cast<void*>(const_cast<T*>(&t));
1251      return DijkstraWizard<SetPathBase<T> >(*this);
1252    }
1253
1254    ///\brief \ref named-func-param "Named parameter"
1255    ///for getting the distance of the target node.
1256    ///
1257    ///\ref named-func-param "Named parameter"
1258    ///for getting the distance of the target node.
1259    DijkstraWizard dist(const Value &d)
1260    {
1261      Base::_di=reinterpret_cast<void*>(const_cast<Value*>(&d));
1262      return *this;
[100]1263    }
[209]1264
[100]1265  };
[209]1266
[278]1267  ///Function-type interface for Dijkstra algorithm.
[100]1268
1269  /// \ingroup shortest_path
[278]1270  ///Function-type interface for Dijkstra algorithm.
[100]1271  ///
[278]1272  ///This function also has several \ref named-func-param "named parameters",
[100]1273  ///they are declared as the members of class \ref DijkstraWizard.
[278]1274  ///The following examples show how to use these parameters.
[100]1275  ///\code
[278]1276  ///  // Compute shortest path from node s to each node
1277  ///  dijkstra(g,length).predMap(preds).distMap(dists).run(s);
1278  ///
1279  ///  // Compute shortest path from s to t
1280  ///  bool reached = dijkstra(g,length).path(p).dist(d).run(s,t);
[100]1281  ///\endcode
[405]1282  ///\warning Don't forget to put the \ref DijkstraWizard::run(Node) "run()"
[100]1283  ///to the end of the parameter list.
1284  ///\sa DijkstraWizard
1285  ///\sa Dijkstra
[559]1286  template<typename GR, typename LEN>
1287  DijkstraWizard<DijkstraWizardBase<GR,LEN> >
1288  dijkstra(const GR &digraph, const LEN &length)
[100]1289  {
[559]1290    return DijkstraWizard<DijkstraWizardBase<GR,LEN> >(digraph,length);
[100]1291  }
1292
1293} //END OF NAMESPACE LEMON
1294
1295#endif
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