[1912] | 1 | /* -*- C++ -*- |
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| 2 | * |
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[1956] | 3 | * This file is a part of LEMON, a generic C++ optimization library |
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| 4 | * |
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[2391] | 5 | * Copyright (C) 2003-2007 |
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[1956] | 6 | * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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[1912] | 7 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
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| 8 | * |
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| 9 | * Permission to use, modify and distribute this software is granted |
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| 10 | * provided that this copyright notice appears in all copies. For |
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| 11 | * precise terms see the accompanying LICENSE file. |
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| 12 | * |
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| 13 | * This software is provided "AS IS" with no warranty of any kind, |
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| 14 | * express or implied, and with no claim as to its suitability for any |
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| 15 | * purpose. |
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| 16 | * |
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| 17 | */ |
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| 18 | |
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| 19 | #ifndef LEMON_DAG_SHORTEST_PATH_H |
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| 20 | #define LEMON_DAG_SHORTEST_PATH_H |
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| 21 | |
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| 22 | ///\ingroup flowalgs |
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| 23 | /// \file |
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| 24 | /// \brief DagShortestPath algorithm. |
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| 25 | /// |
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| 26 | |
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| 27 | #include <lemon/list_graph.h> |
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[1993] | 28 | #include <lemon/bits/invalid.h> |
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[1912] | 29 | #include <lemon/error.h> |
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| 30 | #include <lemon/maps.h> |
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| 31 | #include <lemon/topology.h> |
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| 32 | |
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| 33 | #include <limits> |
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| 34 | |
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| 35 | namespace lemon { |
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| 36 | |
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| 37 | /// \brief Default OperationTraits for the DagShortestPath algorithm class. |
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| 38 | /// |
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| 39 | /// It defines all computational operations and constants which are |
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| 40 | /// used in the dag shortest path algorithm. The default implementation |
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| 41 | /// is based on the numeric_limits class. If the numeric type does not |
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| 42 | /// have infinity value then the maximum value is used as extremal |
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| 43 | /// infinity value. |
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| 44 | template < |
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| 45 | typename Value, |
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| 46 | bool has_infinity = std::numeric_limits<Value>::has_infinity> |
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| 47 | struct DagShortestPathDefaultOperationTraits { |
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| 48 | /// \brief Gives back the zero value of the type. |
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| 49 | static Value zero() { |
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| 50 | return static_cast<Value>(0); |
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| 51 | } |
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| 52 | /// \brief Gives back the positive infinity value of the type. |
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| 53 | static Value infinity() { |
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| 54 | return std::numeric_limits<Value>::infinity(); |
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| 55 | } |
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| 56 | /// \brief Gives back the sum of the given two elements. |
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| 57 | static Value plus(const Value& left, const Value& right) { |
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| 58 | return left + right; |
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| 59 | } |
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| 60 | /// \brief Gives back true only if the first value less than the second. |
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| 61 | static bool less(const Value& left, const Value& right) { |
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| 62 | return left < right; |
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| 63 | } |
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| 64 | }; |
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| 65 | |
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| 66 | template <typename Value> |
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| 67 | struct DagShortestPathDefaultOperationTraits<Value, false> { |
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| 68 | static Value zero() { |
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| 69 | return static_cast<Value>(0); |
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| 70 | } |
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| 71 | static Value infinity() { |
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| 72 | return std::numeric_limits<Value>::max(); |
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| 73 | } |
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| 74 | static Value plus(const Value& left, const Value& right) { |
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| 75 | if (left == infinity() || right == infinity()) return infinity(); |
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| 76 | return left + right; |
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| 77 | } |
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| 78 | static bool less(const Value& left, const Value& right) { |
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| 79 | return left < right; |
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| 80 | } |
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| 81 | }; |
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| 82 | |
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| 83 | /// \brief Default traits class of DagShortestPath class. |
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| 84 | /// |
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| 85 | /// Default traits class of DagShortestPath class. |
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| 86 | /// \param _Graph Graph type. |
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| 87 | /// \param _LegthMap Type of length map. |
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| 88 | template<class _Graph, class _LengthMap> |
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| 89 | struct DagShortestPathDefaultTraits { |
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| 90 | /// The graph type the algorithm runs on. |
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| 91 | typedef _Graph Graph; |
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| 92 | |
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| 93 | /// \brief The type of the map that stores the edge lengths. |
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| 94 | /// |
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| 95 | /// The type of the map that stores the edge lengths. |
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[2260] | 96 | /// It must meet the \ref concepts::ReadMap "ReadMap" concept. |
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[1912] | 97 | typedef _LengthMap LengthMap; |
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| 98 | |
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| 99 | // The type of the length of the edges. |
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| 100 | typedef typename _LengthMap::Value Value; |
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| 101 | |
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| 102 | /// \brief Operation traits for dag shortest path algorithm. |
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| 103 | /// |
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| 104 | /// It defines the infinity type on the given Value type |
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| 105 | /// and the used operation. |
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| 106 | /// \see DagShortestPathDefaultOperationTraits |
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| 107 | typedef DagShortestPathDefaultOperationTraits<Value> OperationTraits; |
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| 108 | |
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| 109 | /// \brief The type of the map that stores the last edges of the |
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| 110 | /// shortest paths. |
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| 111 | /// |
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| 112 | /// The type of the map that stores the last |
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| 113 | /// edges of the shortest paths. |
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[2260] | 114 | /// It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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[1912] | 115 | /// |
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| 116 | typedef typename Graph::template NodeMap<typename _Graph::Edge> PredMap; |
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| 117 | |
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| 118 | /// \brief Instantiates a PredMap. |
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| 119 | /// |
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| 120 | /// This function instantiates a \ref PredMap. |
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[1946] | 121 | /// \param graph is the graph, to which we would |
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| 122 | /// like to define the PredMap. |
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[1912] | 123 | /// \todo The graph alone may be insufficient for the initialization |
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| 124 | static PredMap *createPredMap(const _Graph& graph) { |
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| 125 | return new PredMap(graph); |
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| 126 | } |
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| 127 | |
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| 128 | /// \brief The type of the map that stores the dists of the nodes. |
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| 129 | /// |
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| 130 | /// The type of the map that stores the dists of the nodes. |
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[2260] | 131 | /// It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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[1912] | 132 | /// |
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| 133 | typedef typename Graph::template NodeMap<typename _LengthMap::Value> |
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| 134 | DistMap; |
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| 135 | |
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| 136 | /// \brief Instantiates a DistMap. |
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| 137 | /// |
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| 138 | /// This function instantiates a \ref DistMap. |
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[1946] | 139 | /// \param graph is the graph, to which we would like to define the |
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[1912] | 140 | /// \ref DistMap |
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| 141 | static DistMap *createDistMap(const _Graph& graph) { |
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| 142 | return new DistMap(graph); |
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| 143 | } |
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| 144 | |
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| 145 | }; |
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| 146 | |
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| 147 | /// \brief Inverse OperationTraits for the DagShortestPath algorithm class. |
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| 148 | /// |
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| 149 | /// It defines all computational operations and constants which are |
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| 150 | /// used in the dag shortest path algorithm. It is the inverse of |
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| 151 | /// \ref DagShortestPathDefaultOperationTraits, so it can be used to |
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| 152 | /// calculate the longest path. The default implementation |
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| 153 | /// is based on the numeric_limits class. If the numeric type does not |
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| 154 | /// have infinity value then the minimum value is used as extremal |
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| 155 | /// infinity value. |
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| 156 | template < |
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| 157 | typename Value, |
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| 158 | bool has_infinity = std::numeric_limits<Value>::has_infinity> |
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| 159 | struct DagLongestPathOperationTraits { |
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| 160 | /// \brief Gives back the zero value of the type. |
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| 161 | static Value zero() { |
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| 162 | return static_cast<Value>(0); |
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| 163 | } |
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| 164 | /// \brief Gives back the negative infinity value of the type. |
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| 165 | static Value infinity() { |
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| 166 | return -(std::numeric_limits<Value>::infinity()); |
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| 167 | } |
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| 168 | /// \brief Gives back the sum of the given two elements. |
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| 169 | static Value plus(const Value& left, const Value& right) { |
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| 170 | return left + right; |
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| 171 | } |
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| 172 | /// \brief Gives back true only if the first value less than the second. |
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| 173 | static bool less(const Value& left, const Value& right) { |
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| 174 | return left > right; |
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| 175 | } |
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| 176 | }; |
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| 177 | |
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| 178 | template <typename Value> |
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| 179 | struct DagLongestPathOperationTraits<Value, false> { |
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| 180 | static Value zero() { |
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| 181 | return static_cast<Value>(0); |
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| 182 | } |
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| 183 | static Value infinity() { |
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| 184 | return std::numeric_limits<Value>::min(); |
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| 185 | } |
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| 186 | static Value plus(const Value& left, const Value& right) { |
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| 187 | if (left == infinity() || right == infinity()) return infinity(); |
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| 188 | return left + right; |
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| 189 | } |
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| 190 | static bool less(const Value& left, const Value& right) { |
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| 191 | return left > right; |
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| 192 | } |
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| 193 | }; |
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| 194 | |
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| 195 | /// \brief Inverse traits class of DagShortestPath class. |
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| 196 | /// |
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| 197 | /// Inverse traits class of DagShortestPath class. |
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| 198 | /// \param _Graph Graph type. |
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| 199 | /// \param _LegthMap Type of length map. |
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| 200 | template<class _Graph, class _LengthMap> |
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| 201 | struct DagLongestPathTraits { |
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| 202 | /// The graph type the algorithm runs on. |
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| 203 | typedef _Graph Graph; |
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| 204 | |
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| 205 | /// \brief The type of the map that stores the edge lengths. |
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| 206 | /// |
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| 207 | /// The type of the map that stores the edge lengths. |
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[2260] | 208 | /// It must meet the \ref concepts::ReadMap "ReadMap" concept. |
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[1912] | 209 | typedef _LengthMap LengthMap; |
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| 210 | |
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| 211 | // The type of the length of the edges. |
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| 212 | typedef typename _LengthMap::Value Value; |
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| 213 | |
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| 214 | /// \brief Inverse operation traits for dag shortest path algorithm. |
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| 215 | /// |
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| 216 | /// It defines the infinity type on the given Value type |
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| 217 | /// and the used operation. |
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| 218 | /// \see DagLongestPathOperationTraits |
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| 219 | typedef DagLongestPathOperationTraits<Value> OperationTraits; |
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| 220 | |
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| 221 | /// \brief The type of the map that stores the last edges of the |
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| 222 | /// longest paths. |
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| 223 | /// |
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| 224 | /// The type of the map that stores the last |
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| 225 | /// edges of the longest paths. |
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[2260] | 226 | /// It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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[1912] | 227 | /// |
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| 228 | typedef typename Graph::template NodeMap<typename _Graph::Edge> PredMap; |
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| 229 | |
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| 230 | /// \brief Instantiates a PredMap. |
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| 231 | /// |
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| 232 | /// This function instantiates a \ref PredMap. |
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[1946] | 233 | /// \param graph is the graph, |
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| 234 | /// to which we would like to define the PredMap. |
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[1912] | 235 | /// \todo The graph alone may be insufficient for the initialization |
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| 236 | static PredMap *createPredMap(const _Graph& graph) { |
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| 237 | return new PredMap(graph); |
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| 238 | } |
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| 239 | |
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| 240 | /// \brief The type of the map that stores the dists of the nodes. |
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| 241 | /// |
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| 242 | /// The type of the map that stores the dists of the nodes. |
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[2260] | 243 | /// It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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[1912] | 244 | /// |
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| 245 | typedef typename Graph::template NodeMap<typename _LengthMap::Value> |
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| 246 | DistMap; |
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| 247 | |
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| 248 | /// \brief Instantiates a DistMap. |
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| 249 | /// |
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| 250 | /// This function instantiates a \ref DistMap. |
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[1946] | 251 | /// \param graph is the graph, to which we would like to define the |
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[1912] | 252 | /// \ref DistMap |
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| 253 | static DistMap *createDistMap(const _Graph& graph) { |
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| 254 | return new DistMap(graph); |
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| 255 | } |
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| 256 | |
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| 257 | }; |
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| 258 | |
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| 259 | |
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| 260 | /// \brief %DagShortestPath algorithm class. |
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| 261 | /// |
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| 262 | /// \ingroup flowalgs |
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| 263 | /// This class provides an efficient implementation of a Dag sortest path |
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| 264 | /// searching algorithm. The edge lengths are passed to the algorithm |
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[2260] | 265 | /// using a \ref concepts::ReadMap "ReadMap", so it is easy to change it |
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[1912] | 266 | /// to any kind of length. |
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| 267 | /// |
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| 268 | /// The complexity of the algorithm is O(n + e). |
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| 269 | /// |
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| 270 | /// The type of the length is determined by the |
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[2260] | 271 | /// \ref concepts::ReadMap::Value "Value" of the length map. |
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[1912] | 272 | /// |
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| 273 | /// \param _Graph The graph type the algorithm runs on. The default value |
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| 274 | /// is \ref ListGraph. The value of _Graph is not used directly by |
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| 275 | /// DagShortestPath, it is only passed to \ref DagShortestPathDefaultTraits. |
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| 276 | /// \param _LengthMap This read-only EdgeMap determines the lengths of the |
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[2260] | 277 | /// edges. The default map type is \ref concepts::Graph::EdgeMap |
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[1912] | 278 | /// "Graph::EdgeMap<int>". The value of _LengthMap is not used directly |
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| 279 | /// by DagShortestPath, it is only passed to \ref DagShortestPathDefaultTraits. |
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| 280 | /// \param _Traits Traits class to set various data types used by the |
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| 281 | /// algorithm. The default traits class is \ref DagShortestPathDefaultTraits |
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| 282 | /// "DagShortestPathDefaultTraits<_Graph,_LengthMap>". See \ref |
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| 283 | /// DagShortestPathDefaultTraits for the documentation of a DagShortestPath traits |
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| 284 | /// class. |
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| 285 | /// |
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| 286 | /// \author Balazs Attila Mihaly (based on Balazs Dezso's work) |
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| 287 | |
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| 288 | #ifdef DOXYGEN |
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| 289 | template <typename _Graph, typename _LengthMap, typename _Traits> |
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| 290 | #else |
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| 291 | template <typename _Graph=ListGraph, |
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| 292 | typename _LengthMap=typename _Graph::template EdgeMap<int>, |
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| 293 | typename _Traits=DagShortestPathDefaultTraits<_Graph,_LengthMap> > |
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| 294 | #endif |
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| 295 | class DagShortestPath { |
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| 296 | public: |
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| 297 | |
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| 298 | /// \brief \ref Exception for uninitialized parameters. |
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| 299 | /// |
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| 300 | /// This error represents problems in the initialization |
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| 301 | /// of the parameters of the algorithms. |
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| 302 | |
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| 303 | class UninitializedParameter : public lemon::UninitializedParameter { |
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| 304 | public: |
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[2151] | 305 | virtual const char* what() const throw() { |
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[1912] | 306 | return "lemon::DagShortestPath::UninitializedParameter"; |
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| 307 | } |
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| 308 | }; |
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| 309 | |
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| 310 | typedef _Traits Traits; |
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| 311 | ///The type of the underlying graph. |
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| 312 | typedef typename _Traits::Graph Graph; |
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| 313 | |
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| 314 | typedef typename Graph::Node Node; |
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| 315 | typedef typename Graph::NodeIt NodeIt; |
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| 316 | typedef typename Graph::Edge Edge; |
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| 317 | typedef typename Graph::EdgeIt EdgeIt; |
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| 318 | typedef typename Graph::OutEdgeIt OutEdgeIt; |
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| 319 | |
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| 320 | /// \brief The type of the length of the edges. |
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| 321 | typedef typename _Traits::LengthMap::Value Value; |
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| 322 | /// \brief The type of the map that stores the edge lengths. |
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| 323 | typedef typename _Traits::LengthMap LengthMap; |
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| 324 | /// \brief The type of the map that stores the last |
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| 325 | /// edges of the shortest paths. |
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| 326 | typedef typename _Traits::PredMap PredMap; |
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| 327 | /// \brief The type of the map that stores the dists of the nodes. |
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| 328 | typedef typename _Traits::DistMap DistMap; |
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| 329 | /// \brief The operation traits. |
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| 330 | typedef typename _Traits::OperationTraits OperationTraits; |
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| 331 | /// \brief The Node weight map. |
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[1999] | 332 | typedef typename Graph::template NodeMap<Value> WeightMap; |
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[1912] | 333 | private: |
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| 334 | /// Pointer to the underlying graph |
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| 335 | const Graph *graph; |
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| 336 | /// Pointer to the length map |
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| 337 | const LengthMap *length; |
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| 338 | ///Pointer to the map of predecessors edges |
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| 339 | PredMap *_pred; |
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| 340 | ///Indicates if \ref _pred is locally allocated (\c true) or not |
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| 341 | bool local_pred; |
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| 342 | ///Pointer to the map of distances |
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| 343 | DistMap *_dist; |
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| 344 | ///Indicates if \ref _dist is locally allocated (\c true) or not |
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| 345 | bool local_dist; |
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| 346 | ///Process step counter |
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| 347 | unsigned int _process_step; |
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| 348 | |
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| 349 | std::vector<Node> _node_order; |
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| 350 | |
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| 351 | /// Creates the maps if necessary. |
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| 352 | void create_maps() { |
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| 353 | if(!_pred) { |
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| 354 | local_pred = true; |
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| 355 | _pred = Traits::createPredMap(*graph); |
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| 356 | } |
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| 357 | if(!_dist) { |
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| 358 | local_dist = true; |
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| 359 | _dist = Traits::createDistMap(*graph); |
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| 360 | } |
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| 361 | } |
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| 362 | |
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| 363 | public : |
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| 364 | |
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| 365 | typedef DagShortestPath Create; |
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| 366 | |
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| 367 | /// \name Named template parameters |
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| 368 | |
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| 369 | ///@{ |
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| 370 | |
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| 371 | template <class T> |
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| 372 | struct DefPredMapTraits : public Traits { |
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| 373 | typedef T PredMap; |
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| 374 | static PredMap *createPredMap(const Graph&) { |
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| 375 | throw UninitializedParameter(); |
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| 376 | } |
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| 377 | }; |
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| 378 | |
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| 379 | /// \brief \ref named-templ-param "Named parameter" for setting PredMap |
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| 380 | /// type |
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| 381 | /// \ref named-templ-param "Named parameter" for setting PredMap type |
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| 382 | /// |
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| 383 | template <class T> |
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| 384 | struct DefPredMap { |
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| 385 | typedef DagShortestPath< Graph, LengthMap, DefPredMapTraits<T> > Create; |
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| 386 | }; |
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| 387 | |
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| 388 | template <class T> |
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| 389 | struct DefDistMapTraits : public Traits { |
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| 390 | typedef T DistMap; |
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| 391 | static DistMap *createDistMap(const Graph& graph) { |
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| 392 | throw UninitializedParameter(); |
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| 393 | } |
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| 394 | }; |
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| 395 | |
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| 396 | /// \brief \ref named-templ-param "Named parameter" for setting DistMap |
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| 397 | /// type |
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| 398 | /// |
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| 399 | /// \ref named-templ-param "Named parameter" for setting DistMap type |
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| 400 | /// |
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| 401 | template <class T> |
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| 402 | struct DefDistMap |
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| 403 | : public DagShortestPath< Graph, LengthMap, DefDistMapTraits<T> > { |
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| 404 | typedef DagShortestPath< Graph, LengthMap, DefDistMapTraits<T> > Create; |
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| 405 | }; |
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| 406 | |
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| 407 | template <class T> |
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| 408 | struct DefOperationTraitsTraits : public Traits { |
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| 409 | typedef T OperationTraits; |
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| 410 | }; |
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| 411 | |
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| 412 | /// \brief \ref named-templ-param "Named parameter" for setting |
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| 413 | /// OperationTraits type |
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| 414 | /// |
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| 415 | /// \ref named-templ-param "Named parameter" for setting OperationTraits |
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| 416 | /// type |
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| 417 | template <class T> |
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| 418 | struct DefOperationTraits |
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| 419 | : public DagShortestPath< Graph, LengthMap, DefOperationTraitsTraits<T> > { |
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| 420 | typedef DagShortestPath< Graph, LengthMap, DefOperationTraitsTraits<T> > |
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| 421 | Create; |
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| 422 | }; |
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| 423 | |
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| 424 | ///@} |
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| 425 | |
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| 426 | protected: |
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| 427 | |
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| 428 | DagShortestPath() {} |
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| 429 | |
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| 430 | public: |
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| 431 | |
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| 432 | /// \brief Constructor. |
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| 433 | /// |
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| 434 | /// \param _graph the graph the algorithm will run on. |
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| 435 | /// \param _length the length map used by the algorithm. |
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| 436 | DagShortestPath(const Graph& _graph, const LengthMap& _length) : |
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| 437 | graph(&_graph), length(&_length), |
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| 438 | _pred(0), local_pred(false), |
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| 439 | _dist(0), local_dist(false){} |
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| 440 | |
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| 441 | /// \brief Constructor with node weight map. |
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| 442 | /// |
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| 443 | /// \param _graph the graph the algorithm will run on. |
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| 444 | /// \param _length the length map used by the algorithm. |
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| 445 | /// The NodeMap _length will be used as the weight map. |
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| 446 | /// Each edge will have the weight of its target node. |
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| 447 | DagShortestPath(const Graph& _graph, const WeightMap& _length) : |
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| 448 | graph(&_graph), |
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| 449 | _pred(0), local_pred(false), |
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| 450 | _dist(0), local_dist(false){ |
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| 451 | length=new LengthMap(_graph); |
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| 452 | _dist=new DistMap(_graph); |
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| 453 | for(EdgeIt eit(_graph);eit!=INVALID;++eit) |
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| 454 | (const_cast<LengthMap*>(length))->set(eit,_length[_graph.target(eit)]); |
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| 455 | } |
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| 456 | |
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| 457 | ///Destructor. |
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| 458 | ~DagShortestPath() { |
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| 459 | if(local_pred) delete _pred; |
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| 460 | if(local_dist) delete _dist; |
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| 461 | } |
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| 462 | |
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| 463 | /// \brief Sets the length map. |
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| 464 | /// |
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| 465 | /// Sets the length map. |
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| 466 | /// \return \c (*this) |
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| 467 | DagShortestPath &lengthMap(const LengthMap &m) { |
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| 468 | length = &m; |
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| 469 | return *this; |
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| 470 | } |
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| 471 | |
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| 472 | /// \brief Sets the map storing the predecessor edges. |
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| 473 | /// |
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| 474 | /// Sets the map storing the predecessor edges. |
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| 475 | /// If you don't use this function before calling \ref run(), |
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| 476 | /// it will allocate one. The destuctor deallocates this |
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| 477 | /// automatically allocated map, of course. |
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| 478 | /// \return \c (*this) |
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| 479 | DagShortestPath &predMap(PredMap &m) { |
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| 480 | if(local_pred) { |
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| 481 | delete _pred; |
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| 482 | local_pred=false; |
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| 483 | } |
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| 484 | _pred = &m; |
---|
| 485 | return *this; |
---|
| 486 | } |
---|
| 487 | |
---|
| 488 | /// \brief Sets the map storing the distances calculated by the algorithm. |
---|
| 489 | /// |
---|
| 490 | /// Sets the map storing the distances calculated by the algorithm. |
---|
| 491 | /// If you don't use this function before calling \ref run(), |
---|
| 492 | /// it will allocate one. The destuctor deallocates this |
---|
| 493 | /// automatically allocated map, of course. |
---|
| 494 | /// \return \c (*this) |
---|
| 495 | DagShortestPath &distMap(DistMap &m) { |
---|
| 496 | if(local_dist) { |
---|
| 497 | delete _dist; |
---|
| 498 | local_dist=false; |
---|
| 499 | } |
---|
| 500 | _dist = &m; |
---|
| 501 | return *this; |
---|
| 502 | } |
---|
| 503 | |
---|
| 504 | /// \name Execution control |
---|
| 505 | /// The simplest way to execute the algorithm is to use |
---|
| 506 | /// one of the member functions called \c run(...) |
---|
| 507 | /// \n |
---|
| 508 | /// If you need more control on the execution, |
---|
| 509 | /// first you must call \ref init(...), then you can add several source |
---|
| 510 | /// nodes with \ref addSource(). |
---|
| 511 | /// Finally \ref start() will perform the actual path computation. |
---|
| 512 | /// Some functions have an alternative form (\ref checkedInit(...), |
---|
| 513 | /// \ref checkedRun(...)) which also verifies if the graph given in the |
---|
| 514 | /// constructor is a dag. |
---|
| 515 | |
---|
| 516 | ///@{ |
---|
| 517 | |
---|
| 518 | /// \brief Initializes the internal data structures. |
---|
| 519 | /// |
---|
| 520 | /// Initializes the internal data structures. |
---|
| 521 | void init(const Value value = OperationTraits::infinity()) { |
---|
| 522 | typedef typename Graph::template NodeMap<int> NodeOrderMap; |
---|
| 523 | _process_step=0; |
---|
| 524 | NodeOrderMap node_order(*graph); |
---|
| 525 | topologicalSort(*graph,node_order); |
---|
| 526 | _node_order.resize(countNodes(*graph),INVALID); |
---|
| 527 | create_maps(); |
---|
| 528 | for (NodeIt it(*graph); it != INVALID; ++it) { |
---|
| 529 | _node_order[node_order[it]]=it; |
---|
| 530 | _pred->set(it, INVALID); |
---|
| 531 | _dist->set(it, value); |
---|
| 532 | } |
---|
| 533 | } |
---|
| 534 | |
---|
| 535 | /// \brief Initializes the internal data structures |
---|
| 536 | /// with a given topological sort (NodeMap). |
---|
| 537 | /// |
---|
| 538 | /// Initializes the internal data structures |
---|
| 539 | /// with a given topological sort (NodeMap). |
---|
| 540 | void init(const typename Graph::template NodeMap<int>& node_order, |
---|
| 541 | const Value value = OperationTraits::infinity()) { |
---|
| 542 | _process_step=0; |
---|
| 543 | _node_order.resize(countNodes(*graph),INVALID); |
---|
| 544 | create_maps(); |
---|
| 545 | for (NodeIt it(*graph); it != INVALID; ++it) { |
---|
| 546 | _node_order[node_order[it]]=it; |
---|
| 547 | _pred->set(it, INVALID); |
---|
| 548 | _dist->set(it, value); |
---|
| 549 | } |
---|
| 550 | } |
---|
| 551 | |
---|
| 552 | /// \brief Initializes the internal data structures |
---|
| 553 | /// with a given topological sort (std::vector). |
---|
| 554 | /// |
---|
| 555 | /// Initializes the internal data structures |
---|
| 556 | /// with a given topological sort (std::vector). |
---|
| 557 | void init(const std::vector<Node>& node_order, |
---|
| 558 | const Value value = OperationTraits::infinity()) { |
---|
| 559 | _process_step=0; |
---|
| 560 | _node_order=node_order; |
---|
| 561 | create_maps(); |
---|
| 562 | for (NodeIt it(*graph); it != INVALID; ++it) { |
---|
| 563 | _pred->set(it, INVALID); |
---|
| 564 | _dist->set(it, value); |
---|
| 565 | } |
---|
| 566 | } |
---|
| 567 | |
---|
| 568 | /// \brief Initializes the internal data structures. It also checks if the graph is dag. |
---|
| 569 | /// |
---|
| 570 | /// Initializes the internal data structures. It also checks if the graph is dag. |
---|
| 571 | /// \return true if the graph (given in the constructor) is dag, false otherwise. |
---|
| 572 | bool checkedInit(const Value value = OperationTraits::infinity()) { |
---|
| 573 | typedef typename Graph::template NodeMap<int> NodeOrderMap; |
---|
| 574 | NodeOrderMap node_order(*graph); |
---|
| 575 | if(!checkedTopologicalSort(*graph,node_order))return false; |
---|
| 576 | init(node_order,value); |
---|
| 577 | return true; |
---|
| 578 | } |
---|
| 579 | |
---|
| 580 | /// \brief Initializes the internal data structures with a given |
---|
| 581 | /// topological sort (NodeMap). It also checks if the graph is dag. |
---|
| 582 | /// |
---|
| 583 | /// Initializes the internal data structures with a given |
---|
| 584 | /// topological sort (NodeMap). It also checks if the graph is dag. |
---|
| 585 | /// \return true if the graph (given in the constructor) is dag, false otherwise. |
---|
| 586 | bool checkedInit(const typename Graph::template NodeMap<int>& node_order, |
---|
| 587 | const Value value = OperationTraits::infinity()) { |
---|
| 588 | for(NodeIt it(*graph);it!=INVALID;++it){ |
---|
| 589 | for(OutEdgeIt oeit(*graph,it);oeit!=INVALID;++oeit){ |
---|
| 590 | if(node_order[graph->target(oeit)]<node_order[it])return false; |
---|
| 591 | } |
---|
| 592 | } |
---|
| 593 | init(node_order,value); |
---|
| 594 | return true; |
---|
| 595 | } |
---|
| 596 | |
---|
| 597 | /// \brief Initializes the internal data structures with a given |
---|
| 598 | /// topological sort (std::vector). It also checks if the graph is dag. |
---|
| 599 | /// |
---|
| 600 | /// Initializes the internal data structures with a given |
---|
| 601 | /// topological sort (std::vector). It also checks if the graph is dag. |
---|
| 602 | /// \return true if the graph (given in the constructor) is dag, false otherwise. |
---|
| 603 | bool checkedInit(const std::vector<Node>& node_order, |
---|
| 604 | const Value value = OperationTraits::infinity()) { |
---|
| 605 | typedef typename Graph::template NodeMap<bool> BoolNodeMap; |
---|
| 606 | BoolNodeMap _processed(*graph,false); |
---|
| 607 | for(unsigned int i=0;i<_node_order.size();++i){ |
---|
| 608 | _processed[node_order[i]]=true; |
---|
| 609 | for(OutEdgeIt oeit(*graph,node_order[i]);oeit!=INVALID;++oeit){ |
---|
| 610 | if(_processed[graph->target(oeit)])return false; |
---|
| 611 | } |
---|
| 612 | } |
---|
| 613 | init(node_order,value); |
---|
| 614 | return true; |
---|
| 615 | } |
---|
| 616 | |
---|
| 617 | /// \brief Adds a new source node. |
---|
| 618 | /// |
---|
| 619 | /// The optional second parameter is the initial distance of the node. |
---|
| 620 | /// It just sets the distance of the node to the given value. |
---|
| 621 | void addSource(Node source, Value dst = OperationTraits::zero()) { |
---|
| 622 | if((*_dist)[source] != dst){ |
---|
| 623 | _dist->set(source, dst); |
---|
| 624 | } |
---|
| 625 | } |
---|
| 626 | |
---|
| 627 | /// \brief Executes one step from the dag shortest path algorithm. |
---|
| 628 | /// |
---|
| 629 | /// If the algoritm calculated the distances in the previous step |
---|
| 630 | /// strictly for all at most k length paths then it will calculate the |
---|
| 631 | /// distances strictly for all at most k + 1 length paths. With k |
---|
| 632 | /// iteration this function calculates the at most k length paths. |
---|
| 633 | ///\pre the queue is not empty |
---|
| 634 | ///\return the currently processed node |
---|
| 635 | Node processNextNode() { |
---|
| 636 | if(reached(_node_order[_process_step])){ |
---|
| 637 | for (OutEdgeIt it(*graph, _node_order[_process_step]); it != INVALID; ++it) { |
---|
| 638 | Node target = graph->target(it); |
---|
| 639 | Value relaxed = |
---|
| 640 | OperationTraits::plus((*_dist)[_node_order[_process_step]], (*length)[it]); |
---|
| 641 | if (OperationTraits::less(relaxed, (*_dist)[target])) { |
---|
| 642 | _pred->set(target, it); |
---|
| 643 | _dist->set(target, relaxed); |
---|
| 644 | } |
---|
| 645 | } |
---|
| 646 | } |
---|
| 647 | ++_process_step; |
---|
| 648 | return _node_order[_process_step-1]; |
---|
| 649 | } |
---|
| 650 | |
---|
| 651 | ///\brief Returns \c false if there are nodes |
---|
| 652 | ///to be processed in the queue |
---|
| 653 | /// |
---|
| 654 | ///Returns \c false if there are nodes |
---|
| 655 | ///to be processed in the queue |
---|
| 656 | bool emptyQueue() { return _node_order.size()-1==_process_step; } |
---|
| 657 | |
---|
| 658 | ///\brief Returns the number of the nodes to be processed. |
---|
| 659 | /// |
---|
| 660 | ///Returns the number of the nodes to be processed in the queue. |
---|
| 661 | int queueSize() { return _node_order.size()-1-_process_step; } |
---|
| 662 | |
---|
| 663 | /// \brief Executes the algorithm. |
---|
| 664 | /// |
---|
| 665 | /// \pre init() must be called and at least one node should be added |
---|
| 666 | /// with addSource() before using this function. |
---|
| 667 | /// |
---|
| 668 | /// This method runs the %DagShortestPath algorithm from the root node(s) |
---|
| 669 | /// in order to compute the shortest path to each node. The algorithm |
---|
| 670 | /// computes |
---|
| 671 | /// - The shortest path tree. |
---|
| 672 | /// - The distance of each node from the root(s). |
---|
| 673 | void start() { |
---|
| 674 | while(!emptyQueue()) { |
---|
| 675 | processNextNode(); |
---|
| 676 | } |
---|
| 677 | } |
---|
| 678 | |
---|
| 679 | /// \brief Runs %DagShortestPath algorithm from node \c s. |
---|
| 680 | /// |
---|
| 681 | /// This method runs the %DagShortestPath algorithm from a root node \c s |
---|
| 682 | /// in order to compute the shortest path to each node. The algorithm |
---|
| 683 | /// computes |
---|
| 684 | /// - The shortest path tree. |
---|
| 685 | /// - The distance of each node from the root. |
---|
| 686 | /// |
---|
| 687 | /// \note d.run(s) is just a shortcut of the following code. |
---|
[1946] | 688 | ///\code |
---|
[1912] | 689 | /// d.init(); |
---|
| 690 | /// d.addSource(s); |
---|
| 691 | /// d.start(); |
---|
[1946] | 692 | ///\endcode |
---|
[1912] | 693 | void run(Node s) { |
---|
| 694 | init(); |
---|
| 695 | addSource(s); |
---|
| 696 | start(); |
---|
| 697 | } |
---|
| 698 | |
---|
| 699 | /// \brief Runs %DagShortestPath algorithm from node \c s. |
---|
| 700 | /// It also checks if the graph is a dag. |
---|
| 701 | /// |
---|
| 702 | /// This method runs the %DagShortestPath algorithm from a root node \c s |
---|
| 703 | /// in order to compute the shortest path to each node. The algorithm |
---|
| 704 | /// computes |
---|
| 705 | /// - The shortest path tree. |
---|
| 706 | /// - The distance of each node from the root. |
---|
| 707 | /// The algorithm checks if the graph given int the constructor is a dag. |
---|
| 708 | bool checkedRun(Node s) { |
---|
| 709 | if(!checkedInit())return false; |
---|
| 710 | addSource(s); |
---|
| 711 | start(); |
---|
| 712 | return true; |
---|
| 713 | } |
---|
| 714 | |
---|
| 715 | ///@} |
---|
| 716 | |
---|
| 717 | /// \name Query Functions |
---|
| 718 | /// The result of the %DagShortestPath algorithm can be obtained using these |
---|
| 719 | /// functions.\n |
---|
| 720 | /// Before the use of these functions, |
---|
| 721 | /// either run() or start() must be called. |
---|
| 722 | |
---|
| 723 | ///@{ |
---|
| 724 | |
---|
[2335] | 725 | typedef PredMapPath<Graph, PredMap> Path; |
---|
| 726 | |
---|
| 727 | ///Gives back the shortest path. |
---|
| 728 | |
---|
| 729 | ///Gives back the shortest path. |
---|
| 730 | ///\pre The \c t should be reachable from the source. |
---|
| 731 | Path path(Node t) |
---|
| 732 | { |
---|
| 733 | return Path(*graph, *_pred, t); |
---|
[1912] | 734 | } |
---|
| 735 | |
---|
| 736 | /// \brief The distance of a node from the root. |
---|
| 737 | /// |
---|
| 738 | /// Returns the distance of a node from the root. |
---|
| 739 | /// \pre \ref run() must be called before using this function. |
---|
| 740 | /// \warning If node \c v in unreachable from the root the return value |
---|
| 741 | /// of this funcion is undefined. |
---|
| 742 | Value dist(Node v) const { return (*_dist)[v]; } |
---|
| 743 | |
---|
| 744 | /// \brief Returns the 'previous edge' of the shortest path tree. |
---|
| 745 | /// |
---|
| 746 | /// For a node \c v it returns the 'previous edge' of the shortest path |
---|
| 747 | /// tree, i.e. it returns the last edge of a shortest path from the root |
---|
| 748 | /// to \c v. It is \ref INVALID if \c v is unreachable from the root or |
---|
| 749 | /// if \c v=s. The shortest path tree used here is equal to the shortest |
---|
| 750 | /// path tree used in \ref predNode(). |
---|
| 751 | /// \pre \ref run() must be called before using |
---|
| 752 | /// this function. |
---|
| 753 | Edge predEdge(Node v) const { return (*_pred)[v]; } |
---|
| 754 | |
---|
| 755 | /// \brief Returns the 'previous node' of the shortest path tree. |
---|
| 756 | /// |
---|
| 757 | /// For a node \c v it returns the 'previous node' of the shortest path |
---|
| 758 | /// tree, i.e. it returns the last but one node from a shortest path from |
---|
| 759 | /// the root to \c /v. It is INVALID if \c v is unreachable from the root |
---|
| 760 | /// or if \c v=s. The shortest path tree used here is equal to the |
---|
| 761 | /// shortest path tree used in \ref predEdge(). \pre \ref run() must be |
---|
| 762 | /// called before using this function. |
---|
| 763 | Node predNode(Node v) const { |
---|
| 764 | return (*_pred)[v] == INVALID ? INVALID : graph->source((*_pred)[v]); |
---|
| 765 | } |
---|
| 766 | |
---|
| 767 | /// \brief Returns a reference to the NodeMap of distances. |
---|
| 768 | /// |
---|
| 769 | /// Returns a reference to the NodeMap of distances. \pre \ref run() must |
---|
| 770 | /// be called before using this function. |
---|
| 771 | const DistMap &distMap() const { return *_dist;} |
---|
| 772 | |
---|
| 773 | /// \brief Returns a reference to the shortest path tree map. |
---|
| 774 | /// |
---|
| 775 | /// Returns a reference to the NodeMap of the edges of the |
---|
| 776 | /// shortest path tree. |
---|
| 777 | /// \pre \ref run() must be called before using this function. |
---|
| 778 | const PredMap &predMap() const { return *_pred; } |
---|
| 779 | |
---|
| 780 | /// \brief Checks if a node is reachable from the root. |
---|
| 781 | /// |
---|
| 782 | /// Returns \c true if \c v is reachable from the root. |
---|
| 783 | /// \pre \ref run() must be called before using this function. |
---|
| 784 | /// |
---|
| 785 | bool reached(Node v) { return (*_dist)[v] != OperationTraits::infinity(); } |
---|
| 786 | |
---|
| 787 | ///@} |
---|
| 788 | }; |
---|
| 789 | |
---|
| 790 | /// \brief Default traits class of DagShortestPath function. |
---|
| 791 | /// |
---|
| 792 | /// Default traits class of DagShortestPath function. |
---|
| 793 | /// \param _Graph Graph type. |
---|
| 794 | /// \param _LengthMap Type of length map. |
---|
| 795 | template <typename _Graph, typename _LengthMap> |
---|
| 796 | struct DagShortestPathWizardDefaultTraits { |
---|
| 797 | /// \brief The graph type the algorithm runs on. |
---|
| 798 | typedef _Graph Graph; |
---|
| 799 | |
---|
| 800 | /// \brief The type of the map that stores the edge lengths. |
---|
| 801 | /// |
---|
| 802 | /// The type of the map that stores the edge lengths. |
---|
[2260] | 803 | /// It must meet the \ref concepts::ReadMap "ReadMap" concept. |
---|
[1912] | 804 | typedef _LengthMap LengthMap; |
---|
| 805 | |
---|
| 806 | /// \brief The value type of the length map. |
---|
| 807 | typedef typename _LengthMap::Value Value; |
---|
| 808 | |
---|
| 809 | /// \brief Operation traits for dag shortest path algorithm. |
---|
| 810 | /// |
---|
| 811 | /// It defines the infinity type on the given Value type |
---|
| 812 | /// and the used operation. |
---|
| 813 | /// \see DagShortestPathDefaultOperationTraits |
---|
| 814 | typedef DagShortestPathDefaultOperationTraits<Value> OperationTraits; |
---|
| 815 | |
---|
| 816 | /// \brief The type of the map that stores the last |
---|
| 817 | /// edges of the shortest paths. |
---|
| 818 | /// |
---|
| 819 | /// The type of the map that stores the last |
---|
| 820 | /// edges of the shortest paths. |
---|
[2260] | 821 | /// It must meet the \ref concepts::WriteMap "WriteMap" concept. |
---|
[1912] | 822 | typedef NullMap <typename _Graph::Node,typename _Graph::Edge> PredMap; |
---|
| 823 | |
---|
| 824 | /// \brief Instantiates a PredMap. |
---|
| 825 | /// |
---|
| 826 | /// This function instantiates a \ref PredMap. |
---|
| 827 | static PredMap *createPredMap(const _Graph &) { |
---|
| 828 | return new PredMap(); |
---|
| 829 | } |
---|
| 830 | /// \brief The type of the map that stores the dists of the nodes. |
---|
| 831 | /// |
---|
| 832 | /// The type of the map that stores the dists of the nodes. |
---|
[2260] | 833 | /// It must meet the \ref concepts::WriteMap "WriteMap" concept. |
---|
[1912] | 834 | typedef NullMap<typename Graph::Node, Value> DistMap; |
---|
| 835 | /// \brief Instantiates a DistMap. |
---|
| 836 | /// |
---|
| 837 | /// This function instantiates a \ref DistMap. |
---|
| 838 | static DistMap *createDistMap(const _Graph &) { |
---|
| 839 | return new DistMap(); |
---|
| 840 | } |
---|
| 841 | }; |
---|
| 842 | |
---|
| 843 | /// \brief Default traits used by \ref DagShortestPathWizard |
---|
| 844 | /// |
---|
| 845 | /// To make it easier to use DagShortestPath algorithm |
---|
| 846 | /// we have created a wizard class. |
---|
| 847 | /// This \ref DagShortestPathWizard class needs default traits, |
---|
| 848 | /// as well as the \ref DagShortestPath class. |
---|
| 849 | /// The \ref DagShortestPathWizardBase is a class to be the default traits of the |
---|
| 850 | /// \ref DagShortestPathWizard class. |
---|
| 851 | /// \todo More named parameters are required... |
---|
| 852 | template<class _Graph,class _LengthMap> |
---|
| 853 | class DagShortestPathWizardBase |
---|
| 854 | : public DagShortestPathWizardDefaultTraits<_Graph,_LengthMap> { |
---|
| 855 | |
---|
| 856 | typedef DagShortestPathWizardDefaultTraits<_Graph,_LengthMap> Base; |
---|
| 857 | protected: |
---|
| 858 | /// Type of the nodes in the graph. |
---|
| 859 | typedef typename Base::Graph::Node Node; |
---|
| 860 | |
---|
| 861 | /// Pointer to the underlying graph. |
---|
| 862 | void *_graph; |
---|
| 863 | /// Pointer to the length map |
---|
| 864 | void *_length; |
---|
| 865 | ///Pointer to the map of predecessors edges. |
---|
| 866 | void *_pred; |
---|
| 867 | ///Pointer to the map of distances. |
---|
| 868 | void *_dist; |
---|
| 869 | ///Pointer to the source node. |
---|
| 870 | Node _source; |
---|
| 871 | |
---|
| 872 | public: |
---|
| 873 | /// Constructor. |
---|
| 874 | |
---|
| 875 | /// This constructor does not require parameters, therefore it initiates |
---|
| 876 | /// all of the attributes to default values (0, INVALID). |
---|
| 877 | DagShortestPathWizardBase() : _graph(0), _length(0), _pred(0), |
---|
| 878 | _dist(0), _source(INVALID) {} |
---|
| 879 | |
---|
| 880 | /// Constructor. |
---|
| 881 | |
---|
| 882 | /// This constructor requires some parameters, |
---|
| 883 | /// listed in the parameters list. |
---|
| 884 | /// Others are initiated to 0. |
---|
| 885 | /// \param graph is the initial value of \ref _graph |
---|
| 886 | /// \param length is the initial value of \ref _length |
---|
| 887 | /// \param source is the initial value of \ref _source |
---|
| 888 | DagShortestPathWizardBase(const _Graph& graph, |
---|
| 889 | const _LengthMap& length, |
---|
| 890 | Node source = INVALID) : |
---|
| 891 | _graph((void *)&graph), _length((void *)&length), _pred(0), |
---|
| 892 | _dist(0), _source(source) {} |
---|
| 893 | |
---|
| 894 | }; |
---|
| 895 | |
---|
| 896 | /// A class to make the usage of DagShortestPath algorithm easier |
---|
| 897 | |
---|
| 898 | /// This class is created to make it easier to use DagShortestPath algorithm. |
---|
| 899 | /// It uses the functions and features of the plain \ref DagShortestPath, |
---|
| 900 | /// but it is much simpler to use it. |
---|
| 901 | /// |
---|
| 902 | /// Simplicity means that the way to change the types defined |
---|
| 903 | /// in the traits class is based on functions that returns the new class |
---|
| 904 | /// and not on templatable built-in classes. |
---|
| 905 | /// When using the plain \ref DagShortestPath |
---|
| 906 | /// the new class with the modified type comes from |
---|
| 907 | /// the original class by using the :: |
---|
| 908 | /// operator. In the case of \ref DagShortestPathWizard only |
---|
| 909 | /// a function have to be called and it will |
---|
| 910 | /// return the needed class. |
---|
| 911 | /// |
---|
| 912 | /// It does not have own \ref run method. When its \ref run method is called |
---|
| 913 | /// it initiates a plain \ref DagShortestPath class, and calls the \ref |
---|
| 914 | /// DagShortestPath::run() method of it. |
---|
| 915 | template<class _Traits> |
---|
| 916 | class DagShortestPathWizard : public _Traits { |
---|
| 917 | typedef _Traits Base; |
---|
| 918 | |
---|
| 919 | ///The type of the underlying graph. |
---|
| 920 | typedef typename _Traits::Graph Graph; |
---|
| 921 | |
---|
| 922 | typedef typename Graph::Node Node; |
---|
| 923 | typedef typename Graph::NodeIt NodeIt; |
---|
| 924 | typedef typename Graph::Edge Edge; |
---|
| 925 | typedef typename Graph::OutEdgeIt EdgeIt; |
---|
| 926 | |
---|
| 927 | ///The type of the map that stores the edge lengths. |
---|
| 928 | typedef typename _Traits::LengthMap LengthMap; |
---|
| 929 | |
---|
| 930 | ///The type of the length of the edges. |
---|
| 931 | typedef typename LengthMap::Value Value; |
---|
| 932 | |
---|
| 933 | ///\brief The type of the map that stores the last |
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| 934 | ///edges of the shortest paths. |
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| 935 | typedef typename _Traits::PredMap PredMap; |
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| 936 | |
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| 937 | ///The type of the map that stores the dists of the nodes. |
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| 938 | typedef typename _Traits::DistMap DistMap; |
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| 939 | |
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| 940 | public: |
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| 941 | /// Constructor. |
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| 942 | DagShortestPathWizard() : _Traits() {} |
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| 943 | |
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| 944 | /// \brief Constructor that requires parameters. |
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| 945 | /// |
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| 946 | /// Constructor that requires parameters. |
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| 947 | /// These parameters will be the default values for the traits class. |
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| 948 | DagShortestPathWizard(const Graph& graph, const LengthMap& length, |
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| 949 | Node source = INVALID) |
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| 950 | : _Traits(graph, length, source) {} |
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| 951 | |
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| 952 | /// \brief Copy constructor |
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| 953 | DagShortestPathWizard(const _Traits &b) : _Traits(b) {} |
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| 954 | |
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| 955 | ~DagShortestPathWizard() {} |
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| 956 | |
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| 957 | /// \brief Runs DagShortestPath algorithm from a given node. |
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| 958 | /// |
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| 959 | /// Runs DagShortestPath algorithm from a given node. |
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| 960 | /// The node can be given by the \ref source function. |
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| 961 | void run() { |
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| 962 | if(Base::_source == INVALID) throw UninitializedParameter(); |
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| 963 | DagShortestPath<Graph,LengthMap,_Traits> |
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| 964 | bf(*(Graph*)Base::_graph, *(LengthMap*)Base::_length); |
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| 965 | if (Base::_pred) bf.predMap(*(PredMap*)Base::_pred); |
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| 966 | if (Base::_dist) bf.distMap(*(DistMap*)Base::_dist); |
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| 967 | bf.run(Base::_source); |
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| 968 | } |
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| 969 | |
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| 970 | /// \brief Runs DagShortestPath algorithm from the given node. |
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| 971 | /// |
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| 972 | /// Runs DagShortestPath algorithm from the given node. |
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[1946] | 973 | /// \param source is the given source. |
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[1912] | 974 | void run(Node source) { |
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| 975 | Base::_source = source; |
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| 976 | run(); |
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| 977 | } |
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| 978 | |
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| 979 | template<class T> |
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| 980 | struct DefPredMapBase : public Base { |
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| 981 | typedef T PredMap; |
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| 982 | static PredMap *createPredMap(const Graph &) { return 0; }; |
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| 983 | DefPredMapBase(const _Traits &b) : _Traits(b) {} |
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| 984 | }; |
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| 985 | |
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| 986 | ///\brief \ref named-templ-param "Named parameter" |
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| 987 | ///function for setting PredMap type |
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| 988 | /// |
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| 989 | /// \ref named-templ-param "Named parameter" |
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| 990 | ///function for setting PredMap type |
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| 991 | /// |
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| 992 | template<class T> |
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| 993 | DagShortestPathWizard<DefPredMapBase<T> > predMap(const T &t) |
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| 994 | { |
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| 995 | Base::_pred=(void *)&t; |
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| 996 | return DagShortestPathWizard<DefPredMapBase<T> >(*this); |
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| 997 | } |
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| 998 | |
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| 999 | template<class T> |
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| 1000 | struct DefDistMapBase : public Base { |
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| 1001 | typedef T DistMap; |
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| 1002 | static DistMap *createDistMap(const Graph &) { return 0; }; |
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| 1003 | DefDistMapBase(const _Traits &b) : _Traits(b) {} |
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| 1004 | }; |
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| 1005 | |
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| 1006 | ///\brief \ref named-templ-param "Named parameter" |
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| 1007 | ///function for setting DistMap type |
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| 1008 | /// |
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| 1009 | /// \ref named-templ-param "Named parameter" |
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| 1010 | ///function for setting DistMap type |
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| 1011 | /// |
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| 1012 | template<class T> |
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| 1013 | DagShortestPathWizard<DefDistMapBase<T> > distMap(const T &t) { |
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| 1014 | Base::_dist=(void *)&t; |
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| 1015 | return DagShortestPathWizard<DefDistMapBase<T> >(*this); |
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| 1016 | } |
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| 1017 | |
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| 1018 | template<class T> |
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| 1019 | struct DefOperationTraitsBase : public Base { |
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| 1020 | typedef T OperationTraits; |
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| 1021 | DefOperationTraitsBase(const _Traits &b) : _Traits(b) {} |
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| 1022 | }; |
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| 1023 | |
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| 1024 | ///\brief \ref named-templ-param "Named parameter" |
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| 1025 | ///function for setting OperationTraits type |
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| 1026 | /// |
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| 1027 | /// \ref named-templ-param "Named parameter" |
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| 1028 | ///function for setting OperationTraits type |
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| 1029 | /// |
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| 1030 | template<class T> |
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| 1031 | DagShortestPathWizard<DefOperationTraitsBase<T> > distMap() { |
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| 1032 | return DagShortestPathWizard<DefDistMapBase<T> >(*this); |
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| 1033 | } |
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| 1034 | |
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| 1035 | /// \brief Sets the source node, from which the DagShortestPath algorithm runs. |
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| 1036 | /// |
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| 1037 | /// Sets the source node, from which the DagShortestPath algorithm runs. |
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[1946] | 1038 | /// \param source is the source node. |
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[1912] | 1039 | DagShortestPathWizard<_Traits>& source(Node source) { |
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| 1040 | Base::_source = source; |
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| 1041 | return *this; |
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| 1042 | } |
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| 1043 | |
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| 1044 | }; |
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| 1045 | |
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| 1046 | /// \brief Function type interface for DagShortestPath algorithm. |
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| 1047 | /// |
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| 1048 | /// \ingroup flowalgs |
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| 1049 | /// Function type interface for DagShortestPath algorithm. |
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| 1050 | /// |
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| 1051 | /// This function also has several \ref named-templ-func-param |
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| 1052 | /// "named parameters", they are declared as the members of class |
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| 1053 | /// \ref DagShortestPathWizard. |
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| 1054 | /// The following |
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| 1055 | /// example shows how to use these parameters. |
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[1946] | 1056 | ///\code |
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[1912] | 1057 | /// dagShortestPath(g,length,source).predMap(preds).run(); |
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[1946] | 1058 | ///\endcode |
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[1912] | 1059 | /// \warning Don't forget to put the \ref DagShortestPathWizard::run() "run()" |
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| 1060 | /// to the end of the parameter list. |
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| 1061 | /// \sa DagShortestPathWizard |
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| 1062 | /// \sa DagShortestPath |
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| 1063 | template<class _Graph, class _LengthMap> |
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| 1064 | DagShortestPathWizard<DagShortestPathWizardBase<_Graph,_LengthMap> > |
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| 1065 | dagShortestPath(const _Graph& graph, |
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| 1066 | const _LengthMap& length, |
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| 1067 | typename _Graph::Node source = INVALID) { |
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| 1068 | return DagShortestPathWizard<DagShortestPathWizardBase<_Graph,_LengthMap> > |
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| 1069 | (graph, length, source); |
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| 1070 | } |
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| 1071 | |
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| 1072 | } //END OF NAMESPACE LEMON |
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| 1073 | |
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| 1074 | #endif |
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| 1075 | |
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