[906] | 1 | /* -*- C++ -*- |
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[921] | 2 | * src/lemon/dijkstra.h - Part of LEMON, a generic C++ optimization library |
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[906] | 3 | * |
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| 4 | * Copyright (C) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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| 5 | * (Egervary Combinatorial Optimization Research Group, EGRES). |
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| 6 | * |
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| 7 | * Permission to use, modify and distribute this software is granted |
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| 8 | * provided that this copyright notice appears in all copies. For |
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| 9 | * precise terms see the accompanying LICENSE file. |
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| 10 | * |
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| 11 | * This software is provided "AS IS" with no warranty of any kind, |
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| 12 | * express or implied, and with no claim as to its suitability for any |
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| 13 | * purpose. |
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| 14 | * |
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| 15 | */ |
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| 16 | |
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[921] | 17 | #ifndef LEMON_DIJKSTRA_H |
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| 18 | #define LEMON_DIJKSTRA_H |
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[255] | 19 | |
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[758] | 20 | ///\ingroup flowalgs |
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[255] | 21 | ///\file |
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| 22 | ///\brief Dijkstra algorithm. |
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| 23 | |
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[953] | 24 | #include <lemon/list_graph.h> |
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[921] | 25 | #include <lemon/bin_heap.h> |
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| 26 | #include <lemon/invalid.h> |
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[255] | 27 | |
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[921] | 28 | namespace lemon { |
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[385] | 29 | |
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[758] | 30 | /// \addtogroup flowalgs |
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[430] | 31 | /// @{ |
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| 32 | |
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[954] | 33 | ///Default traits class of Dijkstra class. |
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| 34 | |
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| 35 | ///Default traits class of Dijkstra class. |
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| 36 | ///\param GR Graph type. |
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| 37 | ///\param LM Type of length map. |
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[953] | 38 | template<class GR, class LM> |
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| 39 | struct DijkstraDefaultTraits |
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| 40 | { |
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[954] | 41 | ///The graph type the algorithm runs on. |
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[953] | 42 | typedef GR Graph; |
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| 43 | ///The type of the map that stores the edge lengths. |
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| 44 | |
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[967] | 45 | ///It must meet the \ref concept::ReadMap "ReadMap" concept. |
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[953] | 46 | /// |
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| 47 | typedef LM LengthMap; |
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[954] | 48 | //The type of the length of the edges. |
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[987] | 49 | typedef typename LM::Value Value; |
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[954] | 50 | ///The heap type used by Dijkstra algorithm. |
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[967] | 51 | |
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| 52 | ///The heap type used by Dijkstra algorithm. |
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| 53 | /// |
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| 54 | ///\sa BinHeap |
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| 55 | ///\sa Dijkstra |
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[953] | 56 | typedef BinHeap<typename Graph::Node, |
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[987] | 57 | typename LM::Value, |
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[953] | 58 | typename GR::template NodeMap<int>, |
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[987] | 59 | std::less<Value> > Heap; |
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[953] | 60 | |
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| 61 | ///\brief The type of the map that stores the last |
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| 62 | ///edges of the shortest paths. |
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| 63 | /// |
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[967] | 64 | ///It must meet the \ref concept::WriteMap "WriteMap" concept. |
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[953] | 65 | /// |
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[954] | 66 | typedef typename Graph::template NodeMap<typename GR::Edge> PredMap; |
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| 67 | ///Instantiates a PredMap. |
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[953] | 68 | |
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| 69 | ///\todo Please document... |
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| 70 | /// |
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[954] | 71 | static PredMap *createPredMap(const GR &G) |
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[953] | 72 | { |
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| 73 | return new PredMap(G); |
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| 74 | } |
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| 75 | ///\brief The type of the map that stores the last but one |
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| 76 | ///nodes of the shortest paths. |
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| 77 | /// |
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[967] | 78 | ///It must meet the \ref concept::WriteMap "WriteMap" concept. |
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[953] | 79 | /// |
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[954] | 80 | typedef typename Graph::template NodeMap<typename GR::Node> PredNodeMap; |
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| 81 | ///Instantiates a PredNodeMap. |
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[953] | 82 | |
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| 83 | ///\todo Please document... |
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[967] | 84 | /// |
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[954] | 85 | static PredNodeMap *createPredNodeMap(const GR &G) |
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[953] | 86 | { |
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| 87 | return new PredNodeMap(G); |
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| 88 | } |
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| 89 | ///The type of the map that stores the dists of the nodes. |
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| 90 | |
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[967] | 91 | ///It must meet the \ref concept::WriteMap "WriteMap" concept. |
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[953] | 92 | /// |
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[987] | 93 | typedef typename Graph::template NodeMap<typename LM::Value> DistMap; |
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[954] | 94 | ///Instantiates a DistMap. |
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[953] | 95 | |
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| 96 | ///\todo Please document... |
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| 97 | /// |
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[954] | 98 | static DistMap *createDistMap(const GR &G) |
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[953] | 99 | { |
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| 100 | return new DistMap(G); |
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| 101 | } |
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| 102 | }; |
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| 103 | |
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[255] | 104 | ///%Dijkstra algorithm class. |
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| 105 | |
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| 106 | ///This class provides an efficient implementation of %Dijkstra algorithm. |
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| 107 | ///The edge lengths are passed to the algorithm using a |
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[959] | 108 | ///\ref concept::ReadMap "ReadMap", |
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[255] | 109 | ///so it is easy to change it to any kind of length. |
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| 110 | /// |
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[880] | 111 | ///The type of the length is determined by the |
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[987] | 112 | ///\ref concept::ReadMap::Value "Value" of the length map. |
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[255] | 113 | /// |
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| 114 | ///It is also possible to change the underlying priority heap. |
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| 115 | /// |
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[953] | 116 | ///\param GR The graph type the algorithm runs on. The default value is |
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[955] | 117 | ///\ref ListGraph. The value of GR is not used directly by Dijkstra, it |
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[954] | 118 | ///is only passed to \ref DijkstraDefaultTraits. |
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[584] | 119 | ///\param LM This read-only |
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[385] | 120 | ///EdgeMap |
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| 121 | ///determines the |
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| 122 | ///lengths of the edges. It is read once for each edge, so the map |
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| 123 | ///may involve in relatively time consuming process to compute the edge |
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| 124 | ///length if it is necessary. The default map type is |
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[959] | 125 | ///\ref concept::StaticGraph::EdgeMap "Graph::EdgeMap<int>". |
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[955] | 126 | ///The value of LM is not used directly by Dijkstra, it |
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[954] | 127 | ///is only passed to \ref DijkstraDefaultTraits. |
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| 128 | ///\param TR Traits class to set various data types used by the algorithm. |
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| 129 | ///The default traits class is |
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[955] | 130 | ///\ref DijkstraDefaultTraits "DijkstraDefaultTraits<GR,LM>". |
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[954] | 131 | ///See \ref DijkstraDefaultTraits for the documentation of |
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| 132 | ///a Dijkstra traits class. |
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[456] | 133 | /// |
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[689] | 134 | ///\author Jacint Szabo and Alpar Juttner |
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[693] | 135 | ///\todo We need a typedef-names should be standardized. (-: |
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[584] | 136 | |
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[255] | 137 | #ifdef DOXYGEN |
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[584] | 138 | template <typename GR, |
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| 139 | typename LM, |
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[953] | 140 | typename TR> |
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[255] | 141 | #else |
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[953] | 142 | template <typename GR=ListGraph, |
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[584] | 143 | typename LM=typename GR::template EdgeMap<int>, |
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[953] | 144 | typename TR=DijkstraDefaultTraits<GR,LM> > |
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[255] | 145 | #endif |
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[1116] | 146 | class Dijkstra { |
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[255] | 147 | public: |
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[953] | 148 | typedef TR Traits; |
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[584] | 149 | ///The type of the underlying graph. |
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[954] | 150 | typedef typename TR::Graph Graph; |
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[911] | 151 | ///\e |
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[255] | 152 | typedef typename Graph::Node Node; |
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[911] | 153 | ///\e |
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[255] | 154 | typedef typename Graph::NodeIt NodeIt; |
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[911] | 155 | ///\e |
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[255] | 156 | typedef typename Graph::Edge Edge; |
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[911] | 157 | ///\e |
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[255] | 158 | typedef typename Graph::OutEdgeIt OutEdgeIt; |
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| 159 | |
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[584] | 160 | ///The type of the length of the edges. |
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[987] | 161 | typedef typename TR::LengthMap::Value Value; |
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[693] | 162 | ///The type of the map that stores the edge lengths. |
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[954] | 163 | typedef typename TR::LengthMap LengthMap; |
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[693] | 164 | ///\brief The type of the map that stores the last |
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[584] | 165 | ///edges of the shortest paths. |
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[953] | 166 | typedef typename TR::PredMap PredMap; |
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[693] | 167 | ///\brief The type of the map that stores the last but one |
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[584] | 168 | ///nodes of the shortest paths. |
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[953] | 169 | typedef typename TR::PredNodeMap PredNodeMap; |
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[693] | 170 | ///The type of the map that stores the dists of the nodes. |
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[953] | 171 | typedef typename TR::DistMap DistMap; |
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| 172 | ///The heap type used by the dijkstra algorithm. |
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| 173 | typedef typename TR::Heap Heap; |
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[255] | 174 | private: |
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[802] | 175 | /// Pointer to the underlying graph. |
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[688] | 176 | const Graph *G; |
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[802] | 177 | /// Pointer to the length map |
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[954] | 178 | const LengthMap *length; |
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[802] | 179 | ///Pointer to the map of predecessors edges. |
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[688] | 180 | PredMap *predecessor; |
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[802] | 181 | ///Indicates if \ref predecessor is locally allocated (\c true) or not. |
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[688] | 182 | bool local_predecessor; |
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[802] | 183 | ///Pointer to the map of predecessors nodes. |
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[688] | 184 | PredNodeMap *pred_node; |
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[802] | 185 | ///Indicates if \ref pred_node is locally allocated (\c true) or not. |
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[688] | 186 | bool local_pred_node; |
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[802] | 187 | ///Pointer to the map of distances. |
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[688] | 188 | DistMap *distance; |
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[802] | 189 | ///Indicates if \ref distance is locally allocated (\c true) or not. |
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[688] | 190 | bool local_distance; |
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| 191 | |
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[802] | 192 | ///The source node of the last execution. |
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[774] | 193 | Node source; |
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| 194 | |
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[785] | 195 | ///Initializes the maps. |
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[688] | 196 | |
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[694] | 197 | ///\todo Error if \c G or are \c NULL. What about \c length? |
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[688] | 198 | ///\todo Better memory allocation (instead of new). |
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| 199 | void init_maps() |
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| 200 | { |
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| 201 | if(!predecessor) { |
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| 202 | local_predecessor = true; |
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[953] | 203 | predecessor = Traits::createPredMap(*G); |
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[688] | 204 | } |
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| 205 | if(!pred_node) { |
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| 206 | local_pred_node = true; |
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[953] | 207 | pred_node = Traits::createPredNodeMap(*G); |
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[688] | 208 | } |
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| 209 | if(!distance) { |
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| 210 | local_distance = true; |
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[953] | 211 | distance = Traits::createDistMap(*G); |
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[688] | 212 | } |
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| 213 | } |
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[255] | 214 | |
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| 215 | public : |
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[1116] | 216 | |
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[953] | 217 | template <class T> |
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[1116] | 218 | struct DefPredMapTraits : public Traits { |
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[953] | 219 | typedef T PredMap; |
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| 220 | ///\todo An exception should be thrown. |
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| 221 | /// |
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| 222 | static PredMap *createPredMap(const Graph &G) |
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| 223 | { |
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| 224 | std::cerr << __FILE__ ":" << __LINE__ << |
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| 225 | ": error: Special maps should be manually created" << std::endl; |
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| 226 | exit(1); |
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| 227 | } |
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| 228 | }; |
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[954] | 229 | ///\ref named-templ-param "Named parameter" for setting PredMap type |
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| 230 | |
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| 231 | ///\ref named-templ-param "Named parameter" for setting PredMap type |
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[1043] | 232 | /// |
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[953] | 233 | template <class T> |
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[1116] | 234 | class DefPredMap : public Dijkstra< Graph, |
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[953] | 235 | LengthMap, |
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[1116] | 236 | DefPredMapTraits<T> > { }; |
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[953] | 237 | |
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| 238 | template <class T> |
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[1116] | 239 | struct DefPredNodeMapTraits : public Traits { |
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[953] | 240 | typedef T PredNodeMap; |
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| 241 | ///\todo An exception should be thrown. |
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| 242 | /// |
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| 243 | static PredNodeMap *createPredNodeMap(const Graph &G) |
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| 244 | { |
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| 245 | std::cerr << __FILE__ ":" << __LINE__ << |
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| 246 | ": error: Special maps should be manually created" << std::endl; |
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| 247 | exit(1); |
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| 248 | } |
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| 249 | }; |
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[954] | 250 | ///\ref named-templ-param "Named parameter" for setting PredNodeMap type |
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| 251 | |
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| 252 | ///\ref named-templ-param "Named parameter" for setting PredNodeMap type |
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[1043] | 253 | /// |
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[953] | 254 | template <class T> |
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[1116] | 255 | class DefPredNodeMap : public Dijkstra< Graph, |
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[953] | 256 | LengthMap, |
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[1116] | 257 | DefPredNodeMapTraits<T> > { }; |
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[953] | 258 | |
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| 259 | template <class T> |
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[1116] | 260 | struct DefDistMapTraits : public Traits { |
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[953] | 261 | typedef T DistMap; |
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| 262 | ///\todo An exception should be thrown. |
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| 263 | /// |
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| 264 | static DistMap *createDistMap(const Graph &G) |
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| 265 | { |
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| 266 | std::cerr << __FILE__ ":" << __LINE__ << |
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| 267 | ": error: Special maps should be manually created" << std::endl; |
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| 268 | exit(1); |
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| 269 | } |
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| 270 | }; |
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[954] | 271 | ///\ref named-templ-param "Named parameter" for setting DistMap type |
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| 272 | |
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| 273 | ///\ref named-templ-param "Named parameter" for setting DistMap type |
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[1043] | 274 | /// |
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[953] | 275 | template <class T> |
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[1116] | 276 | class DefDistMap : public Dijkstra< Graph, |
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[953] | 277 | LengthMap, |
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[1116] | 278 | DefDistMapTraits<T> > { }; |
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[953] | 279 | |
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[802] | 280 | ///Constructor. |
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[255] | 281 | |
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[802] | 282 | ///\param _G the graph the algorithm will run on. |
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| 283 | ///\param _length the length map used by the algorithm. |
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[954] | 284 | Dijkstra(const Graph& _G, const LengthMap& _length) : |
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[688] | 285 | G(&_G), length(&_length), |
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[707] | 286 | predecessor(NULL), local_predecessor(false), |
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| 287 | pred_node(NULL), local_pred_node(false), |
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| 288 | distance(NULL), local_distance(false) |
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[688] | 289 | { } |
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| 290 | |
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[802] | 291 | ///Destructor. |
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[688] | 292 | ~Dijkstra() |
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| 293 | { |
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| 294 | if(local_predecessor) delete predecessor; |
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| 295 | if(local_pred_node) delete pred_node; |
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| 296 | if(local_distance) delete distance; |
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| 297 | } |
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| 298 | |
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| 299 | ///Sets the length map. |
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| 300 | |
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| 301 | ///Sets the length map. |
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| 302 | ///\return <tt> (*this) </tt> |
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[1116] | 303 | Dijkstra &lengthMap(const LengthMap &m) |
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[688] | 304 | { |
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| 305 | length = &m; |
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| 306 | return *this; |
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| 307 | } |
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| 308 | |
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| 309 | ///Sets the map storing the predecessor edges. |
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| 310 | |
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| 311 | ///Sets the map storing the predecessor edges. |
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| 312 | ///If you don't use this function before calling \ref run(), |
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| 313 | ///it will allocate one. The destuctor deallocates this |
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| 314 | ///automatically allocated map, of course. |
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| 315 | ///\return <tt> (*this) </tt> |
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[1116] | 316 | Dijkstra &predMap(PredMap &m) |
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[688] | 317 | { |
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| 318 | if(local_predecessor) { |
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| 319 | delete predecessor; |
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| 320 | local_predecessor=false; |
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| 321 | } |
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| 322 | predecessor = &m; |
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| 323 | return *this; |
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| 324 | } |
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| 325 | |
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| 326 | ///Sets the map storing the predecessor nodes. |
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| 327 | |
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| 328 | ///Sets the map storing the predecessor nodes. |
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| 329 | ///If you don't use this function before calling \ref run(), |
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| 330 | ///it will allocate one. The destuctor deallocates this |
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| 331 | ///automatically allocated map, of course. |
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| 332 | ///\return <tt> (*this) </tt> |
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[1116] | 333 | Dijkstra &predNodeMap(PredNodeMap &m) |
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[688] | 334 | { |
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| 335 | if(local_pred_node) { |
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| 336 | delete pred_node; |
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| 337 | local_pred_node=false; |
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| 338 | } |
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| 339 | pred_node = &m; |
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| 340 | return *this; |
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| 341 | } |
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| 342 | |
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| 343 | ///Sets the map storing the distances calculated by the algorithm. |
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| 344 | |
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| 345 | ///Sets the map storing the distances calculated by the algorithm. |
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| 346 | ///If you don't use this function before calling \ref run(), |
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| 347 | ///it will allocate one. The destuctor deallocates this |
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| 348 | ///automatically allocated map, of course. |
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| 349 | ///\return <tt> (*this) </tt> |
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[1116] | 350 | Dijkstra &distMap(DistMap &m) |
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[688] | 351 | { |
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| 352 | if(local_distance) { |
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| 353 | delete distance; |
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| 354 | local_distance=false; |
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| 355 | } |
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| 356 | distance = &m; |
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| 357 | return *this; |
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| 358 | } |
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[255] | 359 | |
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[694] | 360 | ///Runs %Dijkstra algorithm from node \c s. |
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| 361 | |
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| 362 | ///This method runs the %Dijkstra algorithm from a root node \c s |
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| 363 | ///in order to |
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| 364 | ///compute the |
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| 365 | ///shortest path to each node. The algorithm computes |
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| 366 | ///- The shortest path tree. |
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| 367 | ///- The distance of each node from the root. |
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[954] | 368 | ///\todo heap_map's type could also be in the traits class. |
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[694] | 369 | void run(Node s) { |
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| 370 | |
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| 371 | init_maps(); |
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| 372 | |
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[774] | 373 | source = s; |
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| 374 | |
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| 375 | for ( NodeIt u(*G) ; u!=INVALID ; ++u ) { |
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[694] | 376 | predecessor->set(u,INVALID); |
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| 377 | pred_node->set(u,INVALID); |
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| 378 | } |
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| 379 | |
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[954] | 380 | typename Graph::template NodeMap<int> heap_map(*G,-1); |
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[694] | 381 | |
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[953] | 382 | Heap heap(heap_map); |
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[694] | 383 | |
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| 384 | heap.push(s,0); |
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| 385 | |
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| 386 | while ( !heap.empty() ) { |
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| 387 | |
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| 388 | Node v=heap.top(); |
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[987] | 389 | Value oldvalue=heap[v]; |
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[694] | 390 | heap.pop(); |
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| 391 | distance->set(v, oldvalue); |
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| 392 | |
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| 393 | |
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[774] | 394 | for(OutEdgeIt e(*G,v); e!=INVALID; ++e) { |
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[986] | 395 | Node w=G->target(e); |
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[694] | 396 | switch(heap.state(w)) { |
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[953] | 397 | case Heap::PRE_HEAP: |
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[694] | 398 | heap.push(w,oldvalue+(*length)[e]); |
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| 399 | predecessor->set(w,e); |
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| 400 | pred_node->set(w,v); |
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| 401 | break; |
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[953] | 402 | case Heap::IN_HEAP: |
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[694] | 403 | if ( oldvalue+(*length)[e] < heap[w] ) { |
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| 404 | heap.decrease(w, oldvalue+(*length)[e]); |
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| 405 | predecessor->set(w,e); |
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| 406 | pred_node->set(w,v); |
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| 407 | } |
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| 408 | break; |
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[953] | 409 | case Heap::POST_HEAP: |
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[694] | 410 | break; |
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| 411 | } |
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| 412 | } |
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| 413 | } |
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| 414 | } |
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[255] | 415 | |
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[385] | 416 | ///The distance of a node from the root. |
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[255] | 417 | |
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[385] | 418 | ///Returns the distance of a node from the root. |
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[255] | 419 | ///\pre \ref run() must be called before using this function. |
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[385] | 420 | ///\warning If node \c v in unreachable from the root the return value |
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[255] | 421 | ///of this funcion is undefined. |
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[987] | 422 | Value dist(Node v) const { return (*distance)[v]; } |
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[373] | 423 | |
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[584] | 424 | ///Returns the 'previous edge' of the shortest path tree. |
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[255] | 425 | |
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[584] | 426 | ///For a node \c v it returns the 'previous edge' of the shortest path tree, |
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[785] | 427 | ///i.e. it returns the last edge of a shortest path from the root to \c |
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[688] | 428 | ///v. It is \ref INVALID |
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| 429 | ///if \c v is unreachable from the root or if \c v=s. The |
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[385] | 430 | ///shortest path tree used here is equal to the shortest path tree used in |
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| 431 | ///\ref predNode(Node v). \pre \ref run() must be called before using |
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| 432 | ///this function. |
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[780] | 433 | ///\todo predEdge could be a better name. |
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[688] | 434 | Edge pred(Node v) const { return (*predecessor)[v]; } |
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[373] | 435 | |
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[584] | 436 | ///Returns the 'previous node' of the shortest path tree. |
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[255] | 437 | |
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[584] | 438 | ///For a node \c v it returns the 'previous node' of the shortest path tree, |
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[385] | 439 | ///i.e. it returns the last but one node from a shortest path from the |
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| 440 | ///root to \c /v. It is INVALID if \c v is unreachable from the root or if |
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| 441 | ///\c v=s. The shortest path tree used here is equal to the shortest path |
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| 442 | ///tree used in \ref pred(Node v). \pre \ref run() must be called before |
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| 443 | ///using this function. |
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[688] | 444 | Node predNode(Node v) const { return (*pred_node)[v]; } |
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[255] | 445 | |
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| 446 | ///Returns a reference to the NodeMap of distances. |
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| 447 | |
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[385] | 448 | ///Returns a reference to the NodeMap of distances. \pre \ref run() must |
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| 449 | ///be called before using this function. |
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[688] | 450 | const DistMap &distMap() const { return *distance;} |
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[385] | 451 | |
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[255] | 452 | ///Returns a reference to the shortest path tree map. |
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| 453 | |
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| 454 | ///Returns a reference to the NodeMap of the edges of the |
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| 455 | ///shortest path tree. |
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| 456 | ///\pre \ref run() must be called before using this function. |
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[688] | 457 | const PredMap &predMap() const { return *predecessor;} |
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[385] | 458 | |
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| 459 | ///Returns a reference to the map of nodes of shortest paths. |
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[255] | 460 | |
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| 461 | ///Returns a reference to the NodeMap of the last but one nodes of the |
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[385] | 462 | ///shortest path tree. |
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[255] | 463 | ///\pre \ref run() must be called before using this function. |
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[688] | 464 | const PredNodeMap &predNodeMap() const { return *pred_node;} |
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[255] | 465 | |
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[385] | 466 | ///Checks if a node is reachable from the root. |
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[255] | 467 | |
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[385] | 468 | ///Returns \c true if \c v is reachable from the root. |
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[802] | 469 | ///\note The root node is reported to be reached! |
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[255] | 470 | ///\pre \ref run() must be called before using this function. |
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[385] | 471 | /// |
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[780] | 472 | bool reached(Node v) { return v==source || (*predecessor)[v]!=INVALID; } |
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[255] | 473 | |
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| 474 | }; |
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[953] | 475 | |
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[1116] | 476 | template<class GR,class LM> |
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| 477 | class DijkstraWizardBase : public DijkstraDefaultTraits<GR,LM> |
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| 478 | { |
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| 479 | |
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| 480 | typedef DijkstraDefaultTraits<GR,LM> Base; |
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| 481 | protected: |
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| 482 | /// Pointer to the underlying graph. |
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| 483 | void *_g; |
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| 484 | /// Pointer to the length map |
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| 485 | void *_length; |
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| 486 | ///Pointer to the map of predecessors edges. |
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| 487 | void *_pred; |
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| 488 | ///Pointer to the map of predecessors nodes. |
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| 489 | void *_predNode; |
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| 490 | ///Pointer to the map of distances. |
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| 491 | void *_dist; |
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| 492 | ///Pointer to the source node. |
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| 493 | void *_source; |
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| 494 | |
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| 495 | typedef typename Base::Graph::Node Node; |
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| 496 | |
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| 497 | public: |
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| 498 | DijkstraWizardBase() : _g(0), _length(0), _pred(0), _predNode(0), |
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| 499 | _dist(0), _source(INVALID) {} |
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| 500 | |
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| 501 | DijkstraWizardBase(const GR &g,const LM &l, Node s=INVALID) : |
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| 502 | _g((void *)&g), _length((void *)&l), _pred(0), _predNode(0), |
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| 503 | _dist(0), _source((void *)&s) {} |
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| 504 | |
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| 505 | }; |
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| 506 | |
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[953] | 507 | ///\e |
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| 508 | |
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| 509 | ///\e |
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| 510 | /// |
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| 511 | template<class TR> |
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[1116] | 512 | class DijkstraWizard : public TR |
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[953] | 513 | { |
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[1116] | 514 | typedef TR Base; |
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[953] | 515 | |
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| 516 | ///The type of the underlying graph. |
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| 517 | typedef typename TR::Graph Graph; |
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| 518 | ///\e |
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| 519 | typedef typename Graph::Node Node; |
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| 520 | ///\e |
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| 521 | typedef typename Graph::NodeIt NodeIt; |
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| 522 | ///\e |
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| 523 | typedef typename Graph::Edge Edge; |
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| 524 | ///\e |
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| 525 | typedef typename Graph::OutEdgeIt OutEdgeIt; |
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| 526 | |
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| 527 | ///The type of the map that stores the edge lengths. |
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| 528 | typedef typename TR::LengthMap LengthMap; |
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| 529 | ///The type of the length of the edges. |
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[987] | 530 | typedef typename LengthMap::Value Value; |
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[953] | 531 | ///\brief The type of the map that stores the last |
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| 532 | ///edges of the shortest paths. |
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| 533 | typedef typename TR::PredMap PredMap; |
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| 534 | ///\brief The type of the map that stores the last but one |
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| 535 | ///nodes of the shortest paths. |
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| 536 | typedef typename TR::PredNodeMap PredNodeMap; |
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| 537 | ///The type of the map that stores the dists of the nodes. |
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| 538 | typedef typename TR::DistMap DistMap; |
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| 539 | |
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| 540 | ///The heap type used by the dijkstra algorithm. |
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| 541 | typedef typename TR::Heap Heap; |
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[1116] | 542 | public: |
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| 543 | DijkstraWizard() : TR() {} |
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[953] | 544 | |
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[1116] | 545 | DijkstraWizard(const Graph &g,const LengthMap &l, Node s=INVALID) : |
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| 546 | TR(g,l,s) {} |
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[953] | 547 | |
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[1116] | 548 | DijkstraWizard(const TR &b) : TR(b) {} |
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[953] | 549 | |
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[1116] | 550 | ~DijkstraWizard() {} |
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| 551 | |
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| 552 | ///\e |
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| 553 | void run() |
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[953] | 554 | { |
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[1116] | 555 | Dijkstra<Graph,LengthMap,TR> Dij(*(Graph*)_g,*(LengthMap*)_length); |
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| 556 | if(_pred) Dij.predMap(*(PredMap*)_pred); |
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| 557 | if(_predNode) Dij.predNodeMap(*(PredNodeMap*)_predNode); |
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| 558 | if(_dist) Dij.distMap(*(DistMap*)_dist); |
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| 559 | Dij.run(*(Node*)_source); |
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| 560 | } |
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| 561 | |
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| 562 | ///\e |
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| 563 | void run(Node s) |
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| 564 | { |
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| 565 | _source=(void *)&s; |
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| 566 | run(); |
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[953] | 567 | } |
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| 568 | |
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| 569 | template<class T> |
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[1116] | 570 | struct DefPredMapBase : public Base { |
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| 571 | typedef T PredMap; |
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| 572 | static PredMap *createPredMap(const Graph &G) {}; |
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| 573 | }; |
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[953] | 574 | |
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| 575 | ///\e |
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| 576 | template<class T> |
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[1116] | 577 | DijkstraWizard<DefPredMapBase<T> > predMap(const T &t) |
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[953] | 578 | { |
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[1116] | 579 | _pred=(void *)&t; |
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| 580 | return DijkstraWizard<DefPredMapBase<T> >(*this); |
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[953] | 581 | } |
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| 582 | |
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[1116] | 583 | |
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[953] | 584 | template<class T> |
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[1116] | 585 | struct DefPredNodeMapBase : public Base { |
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| 586 | typedef T PredNodeMap; |
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| 587 | static PredNodeMap *createPredNodeMap(const Graph &G) {}; |
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| 588 | }; |
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| 589 | |
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[953] | 590 | ///\e |
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| 591 | template<class T> |
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[1116] | 592 | DijkstraWizard<DefPredNodeMapBase<T> > predNodeMap(const T &t) |
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[953] | 593 | { |
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[1116] | 594 | _predNode=(void *)&t; |
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| 595 | return DijkstraWizard<DefPredNodeMapBase<T> >(*this); |
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[953] | 596 | } |
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[1116] | 597 | |
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| 598 | template<class T> |
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| 599 | struct DefDistMapBase : public Base { |
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| 600 | typedef T DistMap; |
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| 601 | static DistMap *createDistMap(const Graph &G) {}; |
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| 602 | }; |
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[953] | 603 | |
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| 604 | ///\e |
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| 605 | template<class T> |
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[1116] | 606 | DijkstraWizard<DefDistMapBase<T> > distMap(const T &t) |
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[953] | 607 | { |
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[1116] | 608 | _dist=(void *)&t; |
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| 609 | return DijkstraWizard<DefDistMapBase<T> >(*this); |
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[953] | 610 | } |
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[1116] | 611 | |
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[953] | 612 | ///\e |
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[1116] | 613 | DijkstraWizard<TR> &setSource(Node s) |
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[953] | 614 | { |
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[1116] | 615 | source=(void *)&s; |
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[953] | 616 | return *this; |
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| 617 | } |
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| 618 | |
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| 619 | }; |
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[255] | 620 | |
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[953] | 621 | ///\e |
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| 622 | |
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[954] | 623 | ///\todo Please document... |
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[953] | 624 | /// |
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| 625 | template<class GR, class LM> |
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[1116] | 626 | DijkstraWizard<DijkstraWizardBase<GR,LM> > |
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| 627 | dijkstra(const GR &g,const LM &l,typename GR::Node s=INVALID) |
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[953] | 628 | { |
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[1116] | 629 | return DijkstraWizard<DijkstraWizardBase<GR,LM> >(g,l,s); |
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[953] | 630 | } |
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| 631 | |
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[430] | 632 | /// @} |
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[255] | 633 | |
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[921] | 634 | } //END OF NAMESPACE LEMON |
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[255] | 635 | |
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| 636 | #endif |
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| 637 | |
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| 638 | |
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