[2335] | 1 | /* -*- C++ -*- |
---|
| 2 | * |
---|
| 3 | * This file is a part of LEMON, a generic C++ optimization library |
---|
| 4 | * |
---|
[2391] | 5 | * Copyright (C) 2003-2007 |
---|
[2335] | 6 | * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
---|
| 7 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
---|
| 8 | * |
---|
| 9 | * Permission to use, modify and distribute this software is granted |
---|
| 10 | * provided that this copyright notice appears in all copies. For |
---|
| 11 | * precise terms see the accompanying LICENSE file. |
---|
| 12 | * |
---|
| 13 | * This software is provided "AS IS" with no warranty of any kind, |
---|
| 14 | * express or implied, and with no claim as to its suitability for any |
---|
| 15 | * purpose. |
---|
| 16 | * |
---|
| 17 | */ |
---|
| 18 | |
---|
| 19 | ///\ingroup paths |
---|
| 20 | ///\file |
---|
| 21 | ///\brief Classes for representing paths in graphs. |
---|
| 22 | /// |
---|
| 23 | |
---|
| 24 | #ifndef LEMON_PATH_UTILS_H |
---|
| 25 | #define LEMON_PATH_UTILS_H |
---|
| 26 | |
---|
| 27 | #include <lemon/concepts/path.h> |
---|
[2467] | 28 | #include <lemon/lemon_reader.h> |
---|
| 29 | #include <lemon/lemon_writer.h> |
---|
[2335] | 30 | |
---|
| 31 | namespace lemon { |
---|
| 32 | |
---|
| 33 | namespace _path_bits { |
---|
| 34 | |
---|
| 35 | template <typename Path, typename Enable = void> |
---|
| 36 | struct RevTagIndicator { |
---|
| 37 | static const bool value = false; |
---|
| 38 | }; |
---|
| 39 | |
---|
| 40 | template <typename Graph> |
---|
| 41 | struct RevTagIndicator< |
---|
| 42 | Graph, |
---|
| 43 | typename enable_if<typename Graph::RevTag, void>::type |
---|
| 44 | > { |
---|
| 45 | static const bool value = true; |
---|
| 46 | }; |
---|
| 47 | |
---|
| 48 | template <typename Target, typename Source, |
---|
| 49 | typename BuildEnable = void, typename RevEnable = void> |
---|
| 50 | struct PathCopySelector { |
---|
| 51 | static void copy(Target& target, const Source& source) { |
---|
[2357] | 52 | target.clear(); |
---|
[2335] | 53 | for (typename Source::EdgeIt it(source); it != INVALID; ++it) { |
---|
| 54 | target.addBack(it); |
---|
| 55 | } |
---|
| 56 | } |
---|
| 57 | }; |
---|
| 58 | |
---|
| 59 | template <typename Target, typename Source, typename BuildEnable> |
---|
| 60 | struct PathCopySelector< |
---|
| 61 | Target, Source, BuildEnable, |
---|
| 62 | typename enable_if<typename Source::RevPathTag, void>::type> { |
---|
| 63 | static void copy(Target& target, const Source& source) { |
---|
[2357] | 64 | target.clear(); |
---|
| 65 | for (typename Source::RevEdgeIt it(source); it != INVALID; ++it) { |
---|
[2335] | 66 | target.addFront(it); |
---|
| 67 | } |
---|
| 68 | } |
---|
| 69 | }; |
---|
| 70 | |
---|
| 71 | template <typename Target, typename Source, typename RevEnable> |
---|
| 72 | struct PathCopySelector< |
---|
| 73 | Target, Source, |
---|
| 74 | typename enable_if<typename Target::BuildTag, void>::type, RevEnable> { |
---|
| 75 | static void copy(Target& target, const Source& source) { |
---|
| 76 | target.clear(); |
---|
| 77 | target.build(source); |
---|
| 78 | } |
---|
| 79 | }; |
---|
| 80 | |
---|
| 81 | template <typename Target, typename Source> |
---|
| 82 | struct PathCopySelector< |
---|
| 83 | Target, Source, |
---|
| 84 | typename enable_if<typename Target::BuildTag, void>::type, |
---|
| 85 | typename enable_if<typename Source::RevPathTag, void>::type> { |
---|
| 86 | static void copy(Target& target, const Source& source) { |
---|
| 87 | target.clear(); |
---|
| 88 | target.buildRev(source); |
---|
| 89 | } |
---|
| 90 | }; |
---|
| 91 | |
---|
| 92 | } |
---|
| 93 | |
---|
| 94 | |
---|
| 95 | /// \brief Make of copy of a path. |
---|
| 96 | /// |
---|
| 97 | /// Make of copy of a path. |
---|
| 98 | template <typename Target, typename Source> |
---|
| 99 | void copyPath(Target& target, const Source& source) { |
---|
| 100 | checkConcept<concepts::PathDumper<typename Source::Graph>, Source>(); |
---|
| 101 | _path_bits::PathCopySelector<Target, Source>::copy(target, source); |
---|
| 102 | } |
---|
| 103 | |
---|
| 104 | /// \brief Checks the path's consistency. |
---|
| 105 | /// |
---|
| 106 | /// Checks that each edge's target is the next's source. |
---|
[2350] | 107 | /// |
---|
[2335] | 108 | template <typename Graph, typename Path> |
---|
| 109 | bool checkPath(const Graph& graph, const Path& path) { |
---|
| 110 | typename Path::EdgeIt it(path); |
---|
| 111 | if (it == INVALID) return true; |
---|
| 112 | typename Graph::Node node = graph.target(it); |
---|
| 113 | ++it; |
---|
| 114 | while (it != INVALID) { |
---|
| 115 | if (graph.source(it) != node) return false; |
---|
| 116 | node = graph.target(it); |
---|
| 117 | ++it; |
---|
| 118 | } |
---|
| 119 | return true; |
---|
| 120 | } |
---|
| 121 | |
---|
| 122 | /// \brief Gives back the source of the path |
---|
| 123 | /// |
---|
| 124 | /// Gives back the source of the path. |
---|
| 125 | template <typename Graph, typename Path> |
---|
| 126 | typename Graph::Node pathSource(const Graph& graph, const Path& path) { |
---|
| 127 | return graph.source(path.front()); |
---|
| 128 | } |
---|
| 129 | |
---|
| 130 | /// \brief Gives back the target of the path |
---|
| 131 | /// |
---|
| 132 | /// Gives back the target of the path. |
---|
| 133 | template <typename Graph, typename Path> |
---|
| 134 | typename Graph::Node pathTarget(const Graph& graph, const Path& path) { |
---|
| 135 | return graph.target(path.back()); |
---|
| 136 | } |
---|
[2467] | 137 | |
---|
| 138 | /// \brief Class which helps to iterate the nodes of a path |
---|
| 139 | /// |
---|
| 140 | /// In a sense, the path can be treated as a list of edges. The |
---|
| 141 | /// lemon path type stores just this list. As a consequence it |
---|
| 142 | /// cannot enumerate the nodes in the path and the zero length paths |
---|
| 143 | /// cannot store the node. |
---|
| 144 | /// |
---|
| 145 | /// This class implements the node iterator of a path structure. To |
---|
| 146 | /// provide this feature, the underlying graph should be given to |
---|
| 147 | /// the constructor of the iterator. |
---|
| 148 | template <typename Path> |
---|
| 149 | class PathNodeIt { |
---|
| 150 | private: |
---|
| 151 | const typename Path::Graph *_graph; |
---|
| 152 | typename Path::EdgeIt _it; |
---|
| 153 | typename Path::Graph::Node _nd; |
---|
| 154 | |
---|
| 155 | public: |
---|
| 156 | |
---|
| 157 | typedef typename Path::Graph Graph; |
---|
| 158 | typedef typename Graph::Node Node; |
---|
| 159 | |
---|
| 160 | /// Default constructor |
---|
| 161 | PathNodeIt() {} |
---|
| 162 | /// Invalid constructor |
---|
| 163 | PathNodeIt(Invalid) |
---|
| 164 | : _graph(0), _it(INVALID), _nd(INVALID) {} |
---|
| 165 | /// Constructor |
---|
| 166 | PathNodeIt(const Graph& graph, const Path& path) |
---|
| 167 | : _graph(&graph), _it(path) { |
---|
| 168 | _nd = (_it != INVALID ? _graph->source(_it) : INVALID); |
---|
| 169 | } |
---|
| 170 | /// Constructor |
---|
| 171 | PathNodeIt(const Graph& graph, const Path& path, const Node& src) |
---|
| 172 | : _graph(&graph), _it(path), _nd(src) {} |
---|
| 173 | |
---|
| 174 | ///Conversion to Graph::Node |
---|
| 175 | operator Node() const { |
---|
| 176 | return _nd; |
---|
| 177 | } |
---|
| 178 | |
---|
| 179 | /// Next node |
---|
| 180 | PathNodeIt& operator++() { |
---|
| 181 | if (_it == INVALID) _nd = INVALID; |
---|
| 182 | else { |
---|
| 183 | _nd = _graph->target(_it); |
---|
| 184 | ++_it; |
---|
| 185 | } |
---|
| 186 | return *this; |
---|
| 187 | } |
---|
| 188 | |
---|
| 189 | /// Comparison operator |
---|
| 190 | bool operator==(const PathNodeIt& n) const { |
---|
| 191 | return _it == n._it && _nd == n._nd; |
---|
| 192 | } |
---|
| 193 | /// Comparison operator |
---|
| 194 | bool operator!=(const PathNodeIt& n) const { |
---|
| 195 | return _it != n._it || _nd != n._nd; |
---|
| 196 | } |
---|
| 197 | /// Comparison operator |
---|
| 198 | bool operator<(const PathNodeIt& n) const { |
---|
| 199 | return (_it < n._it && _nd != INVALID); |
---|
| 200 | } |
---|
| 201 | |
---|
| 202 | }; |
---|
| 203 | |
---|
| 204 | /// \brief Item writer for paths |
---|
| 205 | /// |
---|
| 206 | /// This class can write paths into files. You can store paths in |
---|
| 207 | /// distinict mapset or in attributes section. |
---|
| 208 | /// |
---|
| 209 | ///\code |
---|
| 210 | /// GraphWriter<SmartGraph> gw(std::cout, g); |
---|
| 211 | /// NodeMapWriter<SmartGraph> nmw(gw, g, gw); |
---|
| 212 | /// |
---|
| 213 | /// SmartGraph::NodeMap<Path<SmartGraph> > pnm(g); |
---|
| 214 | /// for (SmartGraph::NodeIt n(g); n != INVALID; ++n) { |
---|
| 215 | /// pnm[n] = bfs.path(n); |
---|
| 216 | /// } |
---|
| 217 | /// nmw.writeNodeMap("pnm", pnm, PathWriter<Path<SmartGraph> >(gw)); |
---|
| 218 | /// |
---|
| 219 | /// gw.run(); |
---|
| 220 | ///\endcode |
---|
| 221 | /// |
---|
| 222 | /// \warning Do not use this class to write node or edge map values |
---|
| 223 | /// into usual nodesets or edgesets. You will not be able to read |
---|
| 224 | /// back your paths. Rather use NodeMapWriter, EdgeSetWriter or |
---|
| 225 | /// UEdgeSetWriter to dump paths from maps to lemon file. |
---|
| 226 | template <typename Path> |
---|
| 227 | class PathWriter { |
---|
| 228 | private: |
---|
| 229 | |
---|
| 230 | typedef typename Path::Edge Edge; |
---|
| 231 | std::auto_ptr<_writer_bits::LabelWriterBase<Edge> > edgeLabelWriter; |
---|
| 232 | |
---|
| 233 | public: |
---|
| 234 | |
---|
| 235 | typedef Path Value; |
---|
| 236 | |
---|
| 237 | PathWriter(const PathWriter& pw) { |
---|
| 238 | edgeLabelWriter.reset(pw.edgeLabelWriter->clone()); |
---|
| 239 | } |
---|
| 240 | |
---|
| 241 | /// \brief Constructor |
---|
| 242 | /// |
---|
| 243 | /// The paramter shold be an edge label writer which could |
---|
| 244 | /// be a GraphWriter or an EdgeSetWriter. |
---|
| 245 | template <typename EdgeLabelWriter> |
---|
| 246 | explicit PathWriter(const EdgeLabelWriter& _edgeLabelWriter) { |
---|
| 247 | edgeLabelWriter.reset(new _writer_bits:: |
---|
| 248 | LabelWriter<Edge, EdgeLabelWriter>(_edgeLabelWriter)); |
---|
| 249 | } |
---|
| 250 | |
---|
| 251 | /// \brief Writer function |
---|
| 252 | /// |
---|
| 253 | /// Writes the path to the current stream. The representation |
---|
| 254 | /// is the edge labels beetween parentheses. |
---|
| 255 | void write(std::ostream& os, const Value& value) const { |
---|
| 256 | if (!edgeLabelWriter->isLabelWriter()) { |
---|
| 257 | throw DataFormatError("Cannot find edgeset or label map"); |
---|
| 258 | } |
---|
| 259 | os << '(' << ' '; |
---|
| 260 | for (typename Path::EdgeIt e(value); e != INVALID; ++e) { |
---|
| 261 | edgeLabelWriter->write(os, e); |
---|
| 262 | os << ' '; |
---|
| 263 | } |
---|
| 264 | os << ')'; |
---|
| 265 | } |
---|
| 266 | |
---|
| 267 | }; |
---|
| 268 | |
---|
| 269 | namespace _path_bits { |
---|
| 270 | |
---|
| 271 | template <typename _Graph> |
---|
| 272 | class PathProxy { |
---|
| 273 | public: |
---|
| 274 | typedef False RevPathTag; |
---|
| 275 | |
---|
| 276 | typedef _Graph Graph; |
---|
| 277 | typedef typename Graph::Edge Edge; |
---|
| 278 | |
---|
| 279 | PathProxy(const std::vector<Edge>& edges) |
---|
| 280 | : _edges(edges) {} |
---|
| 281 | |
---|
| 282 | int length() const { |
---|
| 283 | return _edges.size(); |
---|
| 284 | } |
---|
| 285 | |
---|
| 286 | bool empty() const { |
---|
| 287 | return _edges.size() == 0; |
---|
| 288 | } |
---|
| 289 | |
---|
| 290 | class EdgeIt { |
---|
| 291 | public: |
---|
| 292 | EdgeIt() {} |
---|
| 293 | EdgeIt(const PathProxy& path) |
---|
| 294 | : _path(&path), _index(0) {} |
---|
| 295 | |
---|
| 296 | operator const Edge() const { |
---|
| 297 | return _path->_edges[_index]; |
---|
| 298 | } |
---|
| 299 | |
---|
| 300 | EdgeIt& operator++() { |
---|
| 301 | ++_index; |
---|
| 302 | return *this; |
---|
| 303 | } |
---|
| 304 | |
---|
| 305 | bool operator==(Invalid) const { |
---|
| 306 | return int(_path->_edges.size()) == _index; |
---|
| 307 | } |
---|
| 308 | bool operator!=(Invalid) const { |
---|
| 309 | return int(_path->_edges.size()) != _index; |
---|
| 310 | } |
---|
| 311 | |
---|
| 312 | private: |
---|
| 313 | const PathProxy* _path; |
---|
| 314 | int _index; |
---|
| 315 | }; |
---|
| 316 | |
---|
| 317 | private: |
---|
| 318 | const std::vector<Edge>& _edges; |
---|
| 319 | |
---|
| 320 | }; |
---|
| 321 | |
---|
| 322 | } |
---|
| 323 | |
---|
| 324 | /// \brief Item reader for paths |
---|
| 325 | /// |
---|
| 326 | /// This class can read paths from files. You can store paths in |
---|
| 327 | /// distinict mapset or in attributes section. |
---|
| 328 | /// |
---|
| 329 | ///\code |
---|
| 330 | /// GraphReader<SmartGraph> gr(std::cout, g); |
---|
| 331 | /// NodeMapReader<SmartGraph> nmr(gr, g, gr); |
---|
| 332 | /// |
---|
| 333 | /// SmartGraph::NodeMap<Path<SmartGraph> > pnm(g); |
---|
| 334 | /// nmr.readNodeMap("pnm", pnm, PathReader<Path<SmartGraph> >(gr)); |
---|
| 335 | /// |
---|
| 336 | /// gr.run(); |
---|
| 337 | ///\endcode |
---|
| 338 | /// |
---|
| 339 | /// \warning Do not use this class to read node or edge map values |
---|
| 340 | /// from nodesets or edgesets. The edges are not surely constructed |
---|
| 341 | /// when the edge list should be read. Rather use NodeMapReader, |
---|
| 342 | /// EdgeSetReader or UEdgeSetReader to read distinict map sets from file. |
---|
| 343 | template <typename Path> |
---|
| 344 | class PathReader { |
---|
| 345 | private: |
---|
| 346 | |
---|
| 347 | typedef typename Path::Edge Edge; |
---|
| 348 | std::auto_ptr<_reader_bits::LabelReaderBase<Edge> > edgeLabelReader; |
---|
| 349 | |
---|
| 350 | public: |
---|
| 351 | |
---|
| 352 | typedef Path Value; |
---|
| 353 | |
---|
| 354 | PathReader(const PathReader& pw) { |
---|
| 355 | edgeLabelReader.reset(pw.edgeLabelReader->clone()); |
---|
| 356 | } |
---|
| 357 | |
---|
| 358 | /// \brief Constructor |
---|
| 359 | /// |
---|
| 360 | /// The paramter shold be an edge label reader which could |
---|
| 361 | /// be a GraphReader or an EdgeSetReader. |
---|
| 362 | template <typename EdgeLabelReader> |
---|
| 363 | explicit PathReader(const EdgeLabelReader& _edgeLabelReader) { |
---|
| 364 | edgeLabelReader.reset(new _reader_bits:: |
---|
| 365 | LabelReader<Edge, EdgeLabelReader>(_edgeLabelReader)); |
---|
| 366 | } |
---|
| 367 | |
---|
| 368 | |
---|
| 369 | /// \brief Reader function |
---|
| 370 | /// |
---|
| 371 | /// Reads the path from the current stream. The representation |
---|
| 372 | /// is the edge labels beetween parentheses. |
---|
| 373 | void read(std::istream& is, Value& value) const { |
---|
| 374 | if (!edgeLabelReader->isLabelReader()) { |
---|
| 375 | throw DataFormatError("Cannot find edgeset or label map"); |
---|
| 376 | } |
---|
| 377 | char c; |
---|
| 378 | if (!(is >> c) || c != '(') |
---|
| 379 | throw DataFormatError("PathReader format error"); |
---|
| 380 | std::vector<typename Path::Edge> v; |
---|
| 381 | while (is >> c && c != ')') { |
---|
| 382 | is.putback(c); |
---|
| 383 | Edge edge = edgeLabelReader->read(is); |
---|
| 384 | v.push_back(edge); |
---|
| 385 | } |
---|
| 386 | if (!is) throw DataFormatError("PathReader format error"); |
---|
| 387 | copyPath(value, _path_bits::PathProxy<typename Path::Edge>(v)); |
---|
| 388 | } |
---|
| 389 | |
---|
| 390 | }; |
---|
| 391 | |
---|
[2335] | 392 | } |
---|
| 393 | |
---|
| 394 | #endif |
---|