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/* -*- mode: C++; indent-tabs-mode: nil; -*- |
2 | 2 |
* |
3 | 3 |
* This file is a part of LEMON, a generic C++ optimization library. |
4 | 4 |
* |
5 | 5 |
* Copyright (C) 2003-2008 |
6 | 6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
7 | 7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
8 | 8 |
* |
9 | 9 |
* Permission to use, modify and distribute this software is granted |
10 | 10 |
* provided that this copyright notice appears in all copies. For |
11 | 11 |
* precise terms see the accompanying LICENSE file. |
12 | 12 |
* |
13 | 13 |
* This software is provided "AS IS" with no warranty of any kind, |
14 | 14 |
* express or implied, and with no claim as to its suitability for any |
15 | 15 |
* purpose. |
16 | 16 |
* |
17 | 17 |
*/ |
18 | 18 |
|
19 | 19 |
#ifndef LEMON_BFS_H |
20 | 20 |
#define LEMON_BFS_H |
21 | 21 |
|
22 | 22 |
///\ingroup search |
23 | 23 |
///\file |
24 | 24 |
///\brief BFS algorithm. |
25 | 25 |
|
26 | 26 |
#include <lemon/list_graph.h> |
27 | 27 |
#include <lemon/bits/path_dump.h> |
28 | 28 |
#include <lemon/core.h> |
29 | 29 |
#include <lemon/error.h> |
30 | 30 |
#include <lemon/maps.h> |
31 | 31 |
|
32 | 32 |
namespace lemon { |
33 | 33 |
|
34 | 34 |
///Default traits class of Bfs class. |
35 | 35 |
|
36 | 36 |
///Default traits class of Bfs class. |
37 | 37 |
///\tparam GR Digraph type. |
38 | 38 |
template<class GR> |
39 | 39 |
struct BfsDefaultTraits |
40 | 40 |
{ |
41 | 41 |
///The type of the digraph the algorithm runs on. |
42 | 42 |
typedef GR Digraph; |
43 | 43 |
|
44 | 44 |
///\brief The type of the map that stores the predecessor |
45 | 45 |
///arcs of the shortest paths. |
46 | 46 |
/// |
47 | 47 |
///The type of the map that stores the predecessor |
48 | 48 |
///arcs of the shortest paths. |
49 | 49 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
50 | 50 |
typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap; |
51 | 51 |
///Instantiates a \ref PredMap. |
52 | 52 |
|
53 | 53 |
///This function instantiates a \ref PredMap. |
54 | 54 |
///\param g is the digraph, to which we would like to define the |
55 | 55 |
///\ref PredMap. |
56 | 56 |
///\todo The digraph alone may be insufficient to initialize |
57 | 57 |
static PredMap *createPredMap(const Digraph &g) |
58 | 58 |
{ |
59 | 59 |
return new PredMap(g); |
60 | 60 |
} |
61 | 61 |
|
62 | 62 |
///The type of the map that indicates which nodes are processed. |
63 | 63 |
|
64 | 64 |
///The type of the map that indicates which nodes are processed. |
65 | 65 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
66 | 66 |
///By default it is a NullMap. |
67 | 67 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
68 | 68 |
///Instantiates a \ref ProcessedMap. |
69 | 69 |
|
70 | 70 |
///This function instantiates a \ref ProcessedMap. |
71 | 71 |
///\param g is the digraph, to which |
72 | 72 |
///we would like to define the \ref ProcessedMap |
73 | 73 |
#ifdef DOXYGEN |
74 | 74 |
static ProcessedMap *createProcessedMap(const Digraph &g) |
75 | 75 |
#else |
76 | 76 |
static ProcessedMap *createProcessedMap(const Digraph &) |
77 | 77 |
#endif |
78 | 78 |
{ |
79 | 79 |
return new ProcessedMap(); |
80 | 80 |
} |
81 | 81 |
|
82 | 82 |
///The type of the map that indicates which nodes are reached. |
83 | 83 |
|
84 | 84 |
///The type of the map that indicates which nodes are reached. |
85 | 85 |
///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept. |
86 | 86 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
87 | 87 |
///Instantiates a \ref ReachedMap. |
88 | 88 |
|
89 | 89 |
///This function instantiates a \ref ReachedMap. |
90 | 90 |
///\param g is the digraph, to which |
91 | 91 |
///we would like to define the \ref ReachedMap. |
92 | 92 |
static ReachedMap *createReachedMap(const Digraph &g) |
93 | 93 |
{ |
94 | 94 |
return new ReachedMap(g); |
95 | 95 |
} |
96 | 96 |
|
97 | 97 |
///The type of the map that stores the distances of the nodes. |
98 | 98 |
|
99 | 99 |
///The type of the map that stores the distances of the nodes. |
100 | 100 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
101 | 101 |
typedef typename Digraph::template NodeMap<int> DistMap; |
102 | 102 |
///Instantiates a \ref DistMap. |
103 | 103 |
|
104 | 104 |
///This function instantiates a \ref DistMap. |
105 | 105 |
///\param g is the digraph, to which we would like to define the |
106 | 106 |
///\ref DistMap. |
107 | 107 |
static DistMap *createDistMap(const Digraph &g) |
108 | 108 |
{ |
109 | 109 |
return new DistMap(g); |
110 | 110 |
} |
111 | 111 |
}; |
112 | 112 |
|
113 | 113 |
///%BFS algorithm class. |
114 | 114 |
|
115 | 115 |
///\ingroup search |
116 | 116 |
///This class provides an efficient implementation of the %BFS algorithm. |
117 | 117 |
/// |
118 | 118 |
///There is also a \ref bfs() "function type interface" for the BFS |
119 | 119 |
///algorithm, which is convenient in the simplier cases and it can be |
120 | 120 |
///used easier. |
121 | 121 |
/// |
122 | 122 |
///\tparam GR The type of the digraph the algorithm runs on. |
123 | 123 |
///The default value is \ref ListDigraph. The value of GR is not used |
124 | 124 |
///directly by \ref Bfs, it is only passed to \ref BfsDefaultTraits. |
125 | 125 |
///\tparam TR Traits class to set various data types used by the algorithm. |
126 | 126 |
///The default traits class is |
127 | 127 |
///\ref BfsDefaultTraits "BfsDefaultTraits<GR>". |
128 | 128 |
///See \ref BfsDefaultTraits for the documentation of |
129 | 129 |
///a Bfs traits class. |
130 | 130 |
#ifdef DOXYGEN |
131 | 131 |
template <typename GR, |
132 | 132 |
typename TR> |
133 | 133 |
#else |
134 | 134 |
template <typename GR=ListDigraph, |
135 | 135 |
typename TR=BfsDefaultTraits<GR> > |
136 | 136 |
#endif |
137 | 137 |
class Bfs { |
138 | 138 |
public: |
139 | 139 |
///\ref Exception for uninitialized parameters. |
140 | 140 |
|
141 | 141 |
///This error represents problems in the initialization of the |
142 | 142 |
///parameters of the algorithm. |
143 | 143 |
class UninitializedParameter : public lemon::UninitializedParameter { |
144 | 144 |
public: |
145 | 145 |
virtual const char* what() const throw() { |
146 | 146 |
return "lemon::Bfs::UninitializedParameter"; |
147 | 147 |
} |
148 | 148 |
}; |
149 | 149 |
|
150 | 150 |
///The type of the digraph the algorithm runs on. |
151 | 151 |
typedef typename TR::Digraph Digraph; |
152 | 152 |
|
153 | 153 |
///\brief The type of the map that stores the predecessor arcs of the |
154 | 154 |
///shortest paths. |
155 | 155 |
typedef typename TR::PredMap PredMap; |
156 | 156 |
///The type of the map that stores the distances of the nodes. |
157 | 157 |
typedef typename TR::DistMap DistMap; |
158 | 158 |
///The type of the map that indicates which nodes are reached. |
159 | 159 |
typedef typename TR::ReachedMap ReachedMap; |
160 | 160 |
///The type of the map that indicates which nodes are processed. |
161 | 161 |
typedef typename TR::ProcessedMap ProcessedMap; |
162 | 162 |
///The type of the paths. |
163 | 163 |
typedef PredMapPath<Digraph, PredMap> Path; |
164 | 164 |
|
165 | 165 |
///The traits class. |
166 | 166 |
typedef TR Traits; |
167 | 167 |
|
168 | 168 |
private: |
169 | 169 |
|
170 | 170 |
typedef typename Digraph::Node Node; |
171 | 171 |
typedef typename Digraph::NodeIt NodeIt; |
172 | 172 |
typedef typename Digraph::Arc Arc; |
173 | 173 |
typedef typename Digraph::OutArcIt OutArcIt; |
174 | 174 |
|
175 | 175 |
//Pointer to the underlying digraph. |
176 | 176 |
const Digraph *G; |
177 | 177 |
//Pointer to the map of predecessor arcs. |
178 | 178 |
PredMap *_pred; |
179 | 179 |
//Indicates if _pred is locally allocated (true) or not. |
180 | 180 |
bool local_pred; |
181 | 181 |
//Pointer to the map of distances. |
182 | 182 |
DistMap *_dist; |
183 | 183 |
//Indicates if _dist is locally allocated (true) or not. |
184 | 184 |
bool local_dist; |
185 | 185 |
//Pointer to the map of reached status of the nodes. |
186 | 186 |
ReachedMap *_reached; |
187 | 187 |
//Indicates if _reached is locally allocated (true) or not. |
188 | 188 |
bool local_reached; |
189 | 189 |
//Pointer to the map of processed status of the nodes. |
190 | 190 |
ProcessedMap *_processed; |
191 | 191 |
//Indicates if _processed is locally allocated (true) or not. |
192 | 192 |
bool local_processed; |
193 | 193 |
|
194 | 194 |
std::vector<typename Digraph::Node> _queue; |
195 | 195 |
int _queue_head,_queue_tail,_queue_next_dist; |
196 | 196 |
int _curr_dist; |
197 | 197 |
|
198 | 198 |
///Creates the maps if necessary. |
199 | 199 |
///\todo Better memory allocation (instead of new). |
200 | 200 |
void create_maps() |
201 | 201 |
{ |
202 | 202 |
if(!_pred) { |
203 | 203 |
local_pred = true; |
204 | 204 |
_pred = Traits::createPredMap(*G); |
205 | 205 |
} |
206 | 206 |
if(!_dist) { |
207 | 207 |
local_dist = true; |
208 | 208 |
_dist = Traits::createDistMap(*G); |
209 | 209 |
} |
210 | 210 |
if(!_reached) { |
211 | 211 |
local_reached = true; |
212 | 212 |
_reached = Traits::createReachedMap(*G); |
213 | 213 |
} |
214 | 214 |
if(!_processed) { |
215 | 215 |
local_processed = true; |
216 | 216 |
_processed = Traits::createProcessedMap(*G); |
217 | 217 |
} |
218 | 218 |
} |
219 | 219 |
|
220 | 220 |
protected: |
221 | 221 |
|
222 | 222 |
Bfs() {} |
223 | 223 |
|
224 | 224 |
public: |
225 | 225 |
|
226 | 226 |
typedef Bfs Create; |
227 | 227 |
|
228 | 228 |
///\name Named template parameters |
229 | 229 |
|
230 | 230 |
///@{ |
231 | 231 |
|
232 | 232 |
template <class T> |
233 |
struct |
|
233 |
struct SetPredMapTraits : public Traits { |
|
234 | 234 |
typedef T PredMap; |
235 | 235 |
static PredMap *createPredMap(const Digraph &) |
236 | 236 |
{ |
237 | 237 |
throw UninitializedParameter(); |
238 | 238 |
} |
239 | 239 |
}; |
240 | 240 |
///\brief \ref named-templ-param "Named parameter" for setting |
241 | 241 |
///\ref PredMap type. |
242 | 242 |
/// |
243 | 243 |
///\ref named-templ-param "Named parameter" for setting |
244 | 244 |
///\ref PredMap type. |
245 | 245 |
template <class T> |
246 |
struct DefPredMap : public Bfs< Digraph, DefPredMapTraits<T> > { |
|
247 |
typedef Bfs< Digraph, DefPredMapTraits<T> > Create; |
|
246 |
struct SetPredMap : public Bfs< Digraph, SetPredMapTraits<T> > { |
|
247 |
typedef Bfs< Digraph, SetPredMapTraits<T> > Create; |
|
248 | 248 |
}; |
249 | 249 |
|
250 | 250 |
template <class T> |
251 |
struct |
|
251 |
struct SetDistMapTraits : public Traits { |
|
252 | 252 |
typedef T DistMap; |
253 | 253 |
static DistMap *createDistMap(const Digraph &) |
254 | 254 |
{ |
255 | 255 |
throw UninitializedParameter(); |
256 | 256 |
} |
257 | 257 |
}; |
258 | 258 |
///\brief \ref named-templ-param "Named parameter" for setting |
259 | 259 |
///\ref DistMap type. |
260 | 260 |
/// |
261 | 261 |
///\ref named-templ-param "Named parameter" for setting |
262 | 262 |
///\ref DistMap type. |
263 | 263 |
template <class T> |
264 |
struct DefDistMap : public Bfs< Digraph, DefDistMapTraits<T> > { |
|
265 |
typedef Bfs< Digraph, DefDistMapTraits<T> > Create; |
|
264 |
struct SetDistMap : public Bfs< Digraph, SetDistMapTraits<T> > { |
|
265 |
typedef Bfs< Digraph, SetDistMapTraits<T> > Create; |
|
266 | 266 |
}; |
267 | 267 |
|
268 | 268 |
template <class T> |
269 |
struct |
|
269 |
struct SetReachedMapTraits : public Traits { |
|
270 | 270 |
typedef T ReachedMap; |
271 | 271 |
static ReachedMap *createReachedMap(const Digraph &) |
272 | 272 |
{ |
273 | 273 |
throw UninitializedParameter(); |
274 | 274 |
} |
275 | 275 |
}; |
276 | 276 |
///\brief \ref named-templ-param "Named parameter" for setting |
277 | 277 |
///\ref ReachedMap type. |
278 | 278 |
/// |
279 | 279 |
///\ref named-templ-param "Named parameter" for setting |
280 | 280 |
///\ref ReachedMap type. |
281 | 281 |
template <class T> |
282 |
struct DefReachedMap : public Bfs< Digraph, DefReachedMapTraits<T> > { |
|
283 |
typedef Bfs< Digraph, DefReachedMapTraits<T> > Create; |
|
282 |
struct SetReachedMap : public Bfs< Digraph, SetReachedMapTraits<T> > { |
|
283 |
typedef Bfs< Digraph, SetReachedMapTraits<T> > Create; |
|
284 | 284 |
}; |
285 | 285 |
|
286 | 286 |
template <class T> |
287 |
struct |
|
287 |
struct SetProcessedMapTraits : public Traits { |
|
288 | 288 |
typedef T ProcessedMap; |
289 | 289 |
static ProcessedMap *createProcessedMap(const Digraph &) |
290 | 290 |
{ |
291 | 291 |
throw UninitializedParameter(); |
292 | 292 |
} |
293 | 293 |
}; |
294 | 294 |
///\brief \ref named-templ-param "Named parameter" for setting |
295 | 295 |
///\ref ProcessedMap type. |
296 | 296 |
/// |
297 | 297 |
///\ref named-templ-param "Named parameter" for setting |
298 | 298 |
///\ref ProcessedMap type. |
299 | 299 |
template <class T> |
300 |
struct DefProcessedMap : public Bfs< Digraph, DefProcessedMapTraits<T> > { |
|
301 |
typedef Bfs< Digraph, DefProcessedMapTraits<T> > Create; |
|
300 |
struct SetProcessedMap : public Bfs< Digraph, SetProcessedMapTraits<T> > { |
|
301 |
typedef Bfs< Digraph, SetProcessedMapTraits<T> > Create; |
|
302 | 302 |
}; |
303 | 303 |
|
304 |
struct |
|
304 |
struct SetStandardProcessedMapTraits : public Traits { |
|
305 | 305 |
typedef typename Digraph::template NodeMap<bool> ProcessedMap; |
306 | 306 |
static ProcessedMap *createProcessedMap(const Digraph &g) |
307 | 307 |
{ |
308 | 308 |
return new ProcessedMap(g); |
309 | 309 |
} |
310 | 310 |
}; |
311 | 311 |
///\brief \ref named-templ-param "Named parameter" for setting |
312 | 312 |
///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>. |
313 | 313 |
/// |
314 | 314 |
///\ref named-templ-param "Named parameter" for setting |
315 | 315 |
///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>. |
316 | 316 |
///If you don't set it explicitly, it will be automatically allocated. |
317 |
template <class T> |
|
318 |
struct DefProcessedMapToBeDefaultMap : |
|
319 |
public Bfs< Digraph, DefDigraphProcessedMapTraits> { |
|
320 |
typedef Bfs< Digraph, DefDigraphProcessedMapTraits> Create; |
|
317 |
struct SetStandardProcessedMap : |
|
318 |
public Bfs< Digraph, SetStandardProcessedMapTraits > { |
|
319 |
typedef Bfs< Digraph, SetStandardProcessedMapTraits > Create; |
|
321 | 320 |
}; |
322 | 321 |
|
323 | 322 |
///@} |
324 | 323 |
|
325 | 324 |
public: |
326 | 325 |
|
327 | 326 |
///Constructor. |
328 | 327 |
|
329 | 328 |
///Constructor. |
330 | 329 |
///\param g The digraph the algorithm runs on. |
331 | 330 |
Bfs(const Digraph &g) : |
332 | 331 |
G(&g), |
333 | 332 |
_pred(NULL), local_pred(false), |
334 | 333 |
_dist(NULL), local_dist(false), |
335 | 334 |
_reached(NULL), local_reached(false), |
336 | 335 |
_processed(NULL), local_processed(false) |
337 | 336 |
{ } |
338 | 337 |
|
339 | 338 |
///Destructor. |
340 | 339 |
~Bfs() |
341 | 340 |
{ |
342 | 341 |
if(local_pred) delete _pred; |
343 | 342 |
if(local_dist) delete _dist; |
344 | 343 |
if(local_reached) delete _reached; |
345 | 344 |
if(local_processed) delete _processed; |
346 | 345 |
} |
347 | 346 |
|
348 | 347 |
///Sets the map that stores the predecessor arcs. |
349 | 348 |
|
350 | 349 |
///Sets the map that stores the predecessor arcs. |
351 | 350 |
///If you don't use this function before calling \ref run(), |
352 | 351 |
///it will allocate one. The destructor deallocates this |
353 | 352 |
///automatically allocated map, of course. |
354 | 353 |
///\return <tt> (*this) </tt> |
355 | 354 |
Bfs &predMap(PredMap &m) |
356 | 355 |
{ |
357 | 356 |
if(local_pred) { |
358 | 357 |
delete _pred; |
359 | 358 |
local_pred=false; |
360 | 359 |
} |
361 | 360 |
_pred = &m; |
362 | 361 |
return *this; |
363 | 362 |
} |
364 | 363 |
|
365 | 364 |
///Sets the map that indicates which nodes are reached. |
366 | 365 |
|
367 | 366 |
///Sets the map that indicates which nodes are reached. |
368 | 367 |
///If you don't use this function before calling \ref run(), |
369 | 368 |
///it will allocate one. The destructor deallocates this |
370 | 369 |
///automatically allocated map, of course. |
371 | 370 |
///\return <tt> (*this) </tt> |
372 | 371 |
Bfs &reachedMap(ReachedMap &m) |
373 | 372 |
{ |
374 | 373 |
if(local_reached) { |
375 | 374 |
delete _reached; |
376 | 375 |
local_reached=false; |
377 | 376 |
} |
378 | 377 |
_reached = &m; |
379 | 378 |
return *this; |
380 | 379 |
} |
381 | 380 |
|
382 | 381 |
///Sets the map that indicates which nodes are processed. |
383 | 382 |
|
384 | 383 |
///Sets the map that indicates which nodes are processed. |
385 | 384 |
///If you don't use this function before calling \ref run(), |
386 | 385 |
///it will allocate one. The destructor deallocates this |
387 | 386 |
///automatically allocated map, of course. |
388 | 387 |
///\return <tt> (*this) </tt> |
389 | 388 |
Bfs &processedMap(ProcessedMap &m) |
390 | 389 |
{ |
391 | 390 |
if(local_processed) { |
392 | 391 |
delete _processed; |
393 | 392 |
local_processed=false; |
394 | 393 |
} |
395 | 394 |
_processed = &m; |
396 | 395 |
return *this; |
397 | 396 |
} |
398 | 397 |
|
399 | 398 |
///Sets the map that stores the distances of the nodes. |
400 | 399 |
|
401 | 400 |
///Sets the map that stores the distances of the nodes calculated by |
402 | 401 |
///the algorithm. |
403 | 402 |
///If you don't use this function before calling \ref run(), |
404 | 403 |
///it will allocate one. The destructor deallocates this |
405 | 404 |
///automatically allocated map, of course. |
406 | 405 |
///\return <tt> (*this) </tt> |
407 | 406 |
Bfs &distMap(DistMap &m) |
408 | 407 |
{ |
409 | 408 |
if(local_dist) { |
410 | 409 |
delete _dist; |
411 | 410 |
local_dist=false; |
412 | 411 |
} |
413 | 412 |
_dist = &m; |
414 | 413 |
return *this; |
415 | 414 |
} |
416 | 415 |
|
417 | 416 |
public: |
418 | 417 |
|
419 | 418 |
///\name Execution control |
420 | 419 |
///The simplest way to execute the algorithm is to use |
421 | 420 |
///one of the member functions called \ref lemon::Bfs::run() "run()". |
422 | 421 |
///\n |
423 | 422 |
///If you need more control on the execution, first you must call |
424 | 423 |
///\ref lemon::Bfs::init() "init()", then you can add several source |
425 | 424 |
///nodes with \ref lemon::Bfs::addSource() "addSource()". |
426 | 425 |
///Finally \ref lemon::Bfs::start() "start()" will perform the |
427 | 426 |
///actual path computation. |
428 | 427 |
|
429 | 428 |
///@{ |
430 | 429 |
|
431 | 430 |
///Initializes the internal data structures. |
432 | 431 |
|
433 | 432 |
///Initializes the internal data structures. |
434 | 433 |
/// |
435 | 434 |
void init() |
436 | 435 |
{ |
437 | 436 |
create_maps(); |
438 | 437 |
_queue.resize(countNodes(*G)); |
439 | 438 |
_queue_head=_queue_tail=0; |
440 | 439 |
_curr_dist=1; |
441 | 440 |
for ( NodeIt u(*G) ; u!=INVALID ; ++u ) { |
442 | 441 |
_pred->set(u,INVALID); |
443 | 442 |
_reached->set(u,false); |
444 | 443 |
_processed->set(u,false); |
445 | 444 |
} |
446 | 445 |
} |
447 | 446 |
|
448 | 447 |
///Adds a new source node. |
449 | 448 |
|
450 | 449 |
///Adds a new source node to the set of nodes to be processed. |
451 | 450 |
/// |
452 | 451 |
void addSource(Node s) |
453 | 452 |
{ |
454 | 453 |
if(!(*_reached)[s]) |
455 | 454 |
{ |
456 | 455 |
_reached->set(s,true); |
457 | 456 |
_pred->set(s,INVALID); |
458 | 457 |
_dist->set(s,0); |
459 | 458 |
_queue[_queue_head++]=s; |
460 | 459 |
_queue_next_dist=_queue_head; |
461 | 460 |
} |
462 | 461 |
} |
463 | 462 |
|
464 | 463 |
///Processes the next node. |
465 | 464 |
|
466 | 465 |
///Processes the next node. |
467 | 466 |
/// |
468 | 467 |
///\return The processed node. |
469 | 468 |
/// |
470 | 469 |
///\pre The queue must not be empty. |
471 | 470 |
Node processNextNode() |
472 | 471 |
{ |
473 | 472 |
if(_queue_tail==_queue_next_dist) { |
474 | 473 |
_curr_dist++; |
475 | 474 |
_queue_next_dist=_queue_head; |
476 | 475 |
} |
477 | 476 |
Node n=_queue[_queue_tail++]; |
478 | 477 |
_processed->set(n,true); |
479 | 478 |
Node m; |
480 | 479 |
for(OutArcIt e(*G,n);e!=INVALID;++e) |
481 | 480 |
if(!(*_reached)[m=G->target(e)]) { |
482 | 481 |
_queue[_queue_head++]=m; |
483 | 482 |
_reached->set(m,true); |
484 | 483 |
_pred->set(m,e); |
485 | 484 |
_dist->set(m,_curr_dist); |
486 | 485 |
} |
487 | 486 |
return n; |
488 | 487 |
} |
489 | 488 |
|
490 | 489 |
///Processes the next node. |
491 | 490 |
|
492 | 491 |
///Processes the next node and checks if the given target node |
493 | 492 |
///is reached. If the target node is reachable from the processed |
494 | 493 |
///node, then the \c reach parameter will be set to \c true. |
495 | 494 |
/// |
496 | 495 |
///\param target The target node. |
497 | 496 |
///\retval reach Indicates if the target node is reached. |
498 | 497 |
///It should be initially \c false. |
499 | 498 |
/// |
500 | 499 |
///\return The processed node. |
501 | 500 |
/// |
502 | 501 |
///\pre The queue must not be empty. |
503 | 502 |
Node processNextNode(Node target, bool& reach) |
504 | 503 |
{ |
505 | 504 |
if(_queue_tail==_queue_next_dist) { |
506 | 505 |
_curr_dist++; |
507 | 506 |
_queue_next_dist=_queue_head; |
508 | 507 |
} |
509 | 508 |
Node n=_queue[_queue_tail++]; |
510 | 509 |
_processed->set(n,true); |
511 | 510 |
Node m; |
512 | 511 |
for(OutArcIt e(*G,n);e!=INVALID;++e) |
513 | 512 |
if(!(*_reached)[m=G->target(e)]) { |
514 | 513 |
_queue[_queue_head++]=m; |
515 | 514 |
_reached->set(m,true); |
516 | 515 |
_pred->set(m,e); |
517 | 516 |
_dist->set(m,_curr_dist); |
518 | 517 |
reach = reach || (target == m); |
519 | 518 |
} |
520 | 519 |
return n; |
521 | 520 |
} |
522 | 521 |
|
523 | 522 |
///Processes the next node. |
524 | 523 |
|
525 | 524 |
///Processes the next node and checks if at least one of reached |
526 | 525 |
///nodes has \c true value in the \c nm node map. If one node |
527 | 526 |
///with \c true value is reachable from the processed node, then the |
528 | 527 |
///\c rnode parameter will be set to the first of such nodes. |
529 | 528 |
/// |
530 | 529 |
///\param nm A \c bool (or convertible) node map that indicates the |
531 | 530 |
///possible targets. |
532 | 531 |
///\retval rnode The reached target node. |
533 | 532 |
///It should be initially \c INVALID. |
534 | 533 |
/// |
535 | 534 |
///\return The processed node. |
536 | 535 |
/// |
537 | 536 |
///\pre The queue must not be empty. |
538 | 537 |
template<class NM> |
539 | 538 |
Node processNextNode(const NM& nm, Node& rnode) |
540 | 539 |
{ |
541 | 540 |
if(_queue_tail==_queue_next_dist) { |
542 | 541 |
_curr_dist++; |
543 | 542 |
_queue_next_dist=_queue_head; |
544 | 543 |
} |
545 | 544 |
Node n=_queue[_queue_tail++]; |
546 | 545 |
_processed->set(n,true); |
547 | 546 |
Node m; |
548 | 547 |
for(OutArcIt e(*G,n);e!=INVALID;++e) |
549 | 548 |
if(!(*_reached)[m=G->target(e)]) { |
550 | 549 |
_queue[_queue_head++]=m; |
551 | 550 |
_reached->set(m,true); |
552 | 551 |
_pred->set(m,e); |
553 | 552 |
_dist->set(m,_curr_dist); |
554 | 553 |
if (nm[m] && rnode == INVALID) rnode = m; |
555 | 554 |
} |
556 | 555 |
return n; |
557 | 556 |
} |
558 | 557 |
|
559 | 558 |
///The next node to be processed. |
560 | 559 |
|
561 | 560 |
///Returns the next node to be processed or \c INVALID if the queue |
562 | 561 |
///is empty. |
563 | 562 |
Node nextNode() const |
564 | 563 |
{ |
565 | 564 |
return _queue_tail<_queue_head?_queue[_queue_tail]:INVALID; |
566 | 565 |
} |
567 | 566 |
|
568 | 567 |
///\brief Returns \c false if there are nodes |
569 | 568 |
///to be processed. |
570 | 569 |
/// |
571 | 570 |
///Returns \c false if there are nodes |
572 | 571 |
///to be processed in the queue. |
573 | 572 |
bool emptyQueue() const { return _queue_tail==_queue_head; } |
574 | 573 |
|
575 | 574 |
///Returns the number of the nodes to be processed. |
576 | 575 |
|
... | ... |
@@ -812,815 +811,815 @@ |
812 | 811 |
///Returns a const reference to the node map that stores the predecessor |
813 | 812 |
///arcs, which form the shortest path tree. |
814 | 813 |
/// |
815 | 814 |
///\pre Either \ref run() or \ref init() |
816 | 815 |
///must be called before using this function. |
817 | 816 |
const PredMap &predMap() const { return *_pred;} |
818 | 817 |
|
819 | 818 |
///Checks if a node is reachable from the root(s). |
820 | 819 |
|
821 | 820 |
///Returns \c true if \c v is reachable from the root(s). |
822 | 821 |
///\pre Either \ref run() or \ref start() |
823 | 822 |
///must be called before using this function. |
824 | 823 |
bool reached(Node v) const { return (*_reached)[v]; } |
825 | 824 |
|
826 | 825 |
///@} |
827 | 826 |
}; |
828 | 827 |
|
829 | 828 |
///Default traits class of bfs() function. |
830 | 829 |
|
831 | 830 |
///Default traits class of bfs() function. |
832 | 831 |
///\tparam GR Digraph type. |
833 | 832 |
template<class GR> |
834 | 833 |
struct BfsWizardDefaultTraits |
835 | 834 |
{ |
836 | 835 |
///The type of the digraph the algorithm runs on. |
837 | 836 |
typedef GR Digraph; |
838 | 837 |
|
839 | 838 |
///\brief The type of the map that stores the predecessor |
840 | 839 |
///arcs of the shortest paths. |
841 | 840 |
/// |
842 | 841 |
///The type of the map that stores the predecessor |
843 | 842 |
///arcs of the shortest paths. |
844 | 843 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
845 | 844 |
typedef NullMap<typename Digraph::Node,typename Digraph::Arc> PredMap; |
846 | 845 |
///Instantiates a \ref PredMap. |
847 | 846 |
|
848 | 847 |
///This function instantiates a \ref PredMap. |
849 | 848 |
///\param g is the digraph, to which we would like to define the |
850 | 849 |
///\ref PredMap. |
851 | 850 |
///\todo The digraph alone may be insufficient to initialize |
852 | 851 |
#ifdef DOXYGEN |
853 | 852 |
static PredMap *createPredMap(const Digraph &g) |
854 | 853 |
#else |
855 | 854 |
static PredMap *createPredMap(const Digraph &) |
856 | 855 |
#endif |
857 | 856 |
{ |
858 | 857 |
return new PredMap(); |
859 | 858 |
} |
860 | 859 |
|
861 | 860 |
///The type of the map that indicates which nodes are processed. |
862 | 861 |
|
863 | 862 |
///The type of the map that indicates which nodes are processed. |
864 | 863 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
865 | 864 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
866 | 865 |
///Instantiates a \ref ProcessedMap. |
867 | 866 |
|
868 | 867 |
///This function instantiates a \ref ProcessedMap. |
869 | 868 |
///\param g is the digraph, to which |
870 | 869 |
///we would like to define the \ref ProcessedMap. |
871 | 870 |
#ifdef DOXYGEN |
872 | 871 |
static ProcessedMap *createProcessedMap(const Digraph &g) |
873 | 872 |
#else |
874 | 873 |
static ProcessedMap *createProcessedMap(const Digraph &) |
875 | 874 |
#endif |
876 | 875 |
{ |
877 | 876 |
return new ProcessedMap(); |
878 | 877 |
} |
879 | 878 |
|
880 | 879 |
///The type of the map that indicates which nodes are reached. |
881 | 880 |
|
882 | 881 |
///The type of the map that indicates which nodes are reached. |
883 | 882 |
///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept. |
884 | 883 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
885 | 884 |
///Instantiates a \ref ReachedMap. |
886 | 885 |
|
887 | 886 |
///This function instantiates a \ref ReachedMap. |
888 | 887 |
///\param g is the digraph, to which |
889 | 888 |
///we would like to define the \ref ReachedMap. |
890 | 889 |
static ReachedMap *createReachedMap(const Digraph &g) |
891 | 890 |
{ |
892 | 891 |
return new ReachedMap(g); |
893 | 892 |
} |
894 | 893 |
|
895 | 894 |
///The type of the map that stores the distances of the nodes. |
896 | 895 |
|
897 | 896 |
///The type of the map that stores the distances of the nodes. |
898 | 897 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
899 | 898 |
/// |
900 | 899 |
typedef NullMap<typename Digraph::Node,int> DistMap; |
901 | 900 |
///Instantiates a \ref DistMap. |
902 | 901 |
|
903 | 902 |
///This function instantiates a \ref DistMap. |
904 | 903 |
///\param g is the digraph, to which we would like to define |
905 | 904 |
///the \ref DistMap |
906 | 905 |
#ifdef DOXYGEN |
907 | 906 |
static DistMap *createDistMap(const Digraph &g) |
908 | 907 |
#else |
909 | 908 |
static DistMap *createDistMap(const Digraph &) |
910 | 909 |
#endif |
911 | 910 |
{ |
912 | 911 |
return new DistMap(); |
913 | 912 |
} |
914 | 913 |
}; |
915 | 914 |
|
916 | 915 |
/// Default traits class used by \ref BfsWizard |
917 | 916 |
|
918 | 917 |
/// To make it easier to use Bfs algorithm |
919 | 918 |
/// we have created a wizard class. |
920 | 919 |
/// This \ref BfsWizard class needs default traits, |
921 | 920 |
/// as well as the \ref Bfs class. |
922 | 921 |
/// The \ref BfsWizardBase is a class to be the default traits of the |
923 | 922 |
/// \ref BfsWizard class. |
924 | 923 |
template<class GR> |
925 | 924 |
class BfsWizardBase : public BfsWizardDefaultTraits<GR> |
926 | 925 |
{ |
927 | 926 |
|
928 | 927 |
typedef BfsWizardDefaultTraits<GR> Base; |
929 | 928 |
protected: |
930 | 929 |
//The type of the nodes in the digraph. |
931 | 930 |
typedef typename Base::Digraph::Node Node; |
932 | 931 |
|
933 | 932 |
//Pointer to the digraph the algorithm runs on. |
934 | 933 |
void *_g; |
935 | 934 |
//Pointer to the map of reached nodes. |
936 | 935 |
void *_reached; |
937 | 936 |
//Pointer to the map of processed nodes. |
938 | 937 |
void *_processed; |
939 | 938 |
//Pointer to the map of predecessors arcs. |
940 | 939 |
void *_pred; |
941 | 940 |
//Pointer to the map of distances. |
942 | 941 |
void *_dist; |
943 | 942 |
//Pointer to the source node. |
944 | 943 |
Node _source; |
945 | 944 |
|
946 | 945 |
public: |
947 | 946 |
/// Constructor. |
948 | 947 |
|
949 | 948 |
/// This constructor does not require parameters, therefore it initiates |
950 | 949 |
/// all of the attributes to default values (0, INVALID). |
951 | 950 |
BfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0), |
952 | 951 |
_dist(0), _source(INVALID) {} |
953 | 952 |
|
954 | 953 |
/// Constructor. |
955 | 954 |
|
956 | 955 |
/// This constructor requires some parameters, |
957 | 956 |
/// listed in the parameters list. |
958 | 957 |
/// Others are initiated to 0. |
959 | 958 |
/// \param g The digraph the algorithm runs on. |
960 | 959 |
/// \param s The source node. |
961 | 960 |
BfsWizardBase(const GR &g, Node s=INVALID) : |
962 | 961 |
_g(reinterpret_cast<void*>(const_cast<GR*>(&g))), |
963 | 962 |
_reached(0), _processed(0), _pred(0), _dist(0), _source(s) {} |
964 | 963 |
|
965 | 964 |
}; |
966 | 965 |
|
967 | 966 |
/// Auxiliary class for the function type interface of BFS algorithm. |
968 | 967 |
|
969 | 968 |
/// This auxiliary class is created to implement the function type |
970 | 969 |
/// interface of \ref Bfs algorithm. It uses the functions and features |
971 | 970 |
/// of the plain \ref Bfs, but it is much simpler to use it. |
972 | 971 |
/// It should only be used through the \ref bfs() function, which makes |
973 | 972 |
/// it easier to use the algorithm. |
974 | 973 |
/// |
975 | 974 |
/// Simplicity means that the way to change the types defined |
976 | 975 |
/// in the traits class is based on functions that returns the new class |
977 | 976 |
/// and not on templatable built-in classes. |
978 | 977 |
/// When using the plain \ref Bfs |
979 | 978 |
/// the new class with the modified type comes from |
980 | 979 |
/// the original class by using the :: |
981 | 980 |
/// operator. In the case of \ref BfsWizard only |
982 | 981 |
/// a function have to be called, and it will |
983 | 982 |
/// return the needed class. |
984 | 983 |
/// |
985 | 984 |
/// It does not have own \ref run() method. When its \ref run() method |
986 | 985 |
/// is called, it initiates a plain \ref Bfs object, and calls the |
987 | 986 |
/// \ref Bfs::run() method of it. |
988 | 987 |
template<class TR> |
989 | 988 |
class BfsWizard : public TR |
990 | 989 |
{ |
991 | 990 |
typedef TR Base; |
992 | 991 |
|
993 | 992 |
///The type of the digraph the algorithm runs on. |
994 | 993 |
typedef typename TR::Digraph Digraph; |
995 | 994 |
|
996 | 995 |
typedef typename Digraph::Node Node; |
997 | 996 |
typedef typename Digraph::NodeIt NodeIt; |
998 | 997 |
typedef typename Digraph::Arc Arc; |
999 | 998 |
typedef typename Digraph::OutArcIt OutArcIt; |
1000 | 999 |
|
1001 | 1000 |
///\brief The type of the map that stores the predecessor |
1002 | 1001 |
///arcs of the shortest paths. |
1003 | 1002 |
typedef typename TR::PredMap PredMap; |
1004 | 1003 |
///\brief The type of the map that stores the distances of the nodes. |
1005 | 1004 |
typedef typename TR::DistMap DistMap; |
1006 | 1005 |
///\brief The type of the map that indicates which nodes are reached. |
1007 | 1006 |
typedef typename TR::ReachedMap ReachedMap; |
1008 | 1007 |
///\brief The type of the map that indicates which nodes are processed. |
1009 | 1008 |
typedef typename TR::ProcessedMap ProcessedMap; |
1010 | 1009 |
|
1011 | 1010 |
public: |
1012 | 1011 |
|
1013 | 1012 |
/// Constructor. |
1014 | 1013 |
BfsWizard() : TR() {} |
1015 | 1014 |
|
1016 | 1015 |
/// Constructor that requires parameters. |
1017 | 1016 |
|
1018 | 1017 |
/// Constructor that requires parameters. |
1019 | 1018 |
/// These parameters will be the default values for the traits class. |
1020 | 1019 |
BfsWizard(const Digraph &g, Node s=INVALID) : |
1021 | 1020 |
TR(g,s) {} |
1022 | 1021 |
|
1023 | 1022 |
///Copy constructor |
1024 | 1023 |
BfsWizard(const TR &b) : TR(b) {} |
1025 | 1024 |
|
1026 | 1025 |
~BfsWizard() {} |
1027 | 1026 |
|
1028 | 1027 |
///Runs BFS algorithm from a source node. |
1029 | 1028 |
|
1030 | 1029 |
///Runs BFS algorithm from a source node. |
1031 | 1030 |
///The node can be given with the \ref source() function. |
1032 | 1031 |
void run() |
1033 | 1032 |
{ |
1034 | 1033 |
if(Base::_source==INVALID) throw UninitializedParameter(); |
1035 | 1034 |
Bfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g)); |
1036 | 1035 |
if(Base::_reached) |
1037 | 1036 |
alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached)); |
1038 | 1037 |
if(Base::_processed) |
1039 | 1038 |
alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed)); |
1040 | 1039 |
if(Base::_pred) |
1041 | 1040 |
alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred)); |
1042 | 1041 |
if(Base::_dist) |
1043 | 1042 |
alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist)); |
1044 | 1043 |
alg.run(Base::_source); |
1045 | 1044 |
} |
1046 | 1045 |
|
1047 | 1046 |
///Runs BFS algorithm from the given node. |
1048 | 1047 |
|
1049 | 1048 |
///Runs BFS algorithm from the given node. |
1050 | 1049 |
///\param s is the given source. |
1051 | 1050 |
void run(Node s) |
1052 | 1051 |
{ |
1053 | 1052 |
Base::_source=s; |
1054 | 1053 |
run(); |
1055 | 1054 |
} |
1056 | 1055 |
|
1057 | 1056 |
/// Sets the source node, from which the Bfs algorithm runs. |
1058 | 1057 |
|
1059 | 1058 |
/// Sets the source node, from which the Bfs algorithm runs. |
1060 | 1059 |
/// \param s is the source node. |
1061 | 1060 |
BfsWizard<TR> &source(Node s) |
1062 | 1061 |
{ |
1063 | 1062 |
Base::_source=s; |
1064 | 1063 |
return *this; |
1065 | 1064 |
} |
1066 | 1065 |
|
1067 | 1066 |
template<class T> |
1068 |
struct |
|
1067 |
struct SetPredMapBase : public Base { |
|
1069 | 1068 |
typedef T PredMap; |
1070 | 1069 |
static PredMap *createPredMap(const Digraph &) { return 0; }; |
1071 |
|
|
1070 |
SetPredMapBase(const TR &b) : TR(b) {} |
|
1072 | 1071 |
}; |
1073 | 1072 |
///\brief \ref named-templ-param "Named parameter" |
1074 | 1073 |
///for setting \ref PredMap object. |
1075 | 1074 |
/// |
1076 | 1075 |
/// \ref named-templ-param "Named parameter" |
1077 | 1076 |
///for setting \ref PredMap object. |
1078 | 1077 |
template<class T> |
1079 |
BfsWizard< |
|
1078 |
BfsWizard<SetPredMapBase<T> > predMap(const T &t) |
|
1080 | 1079 |
{ |
1081 | 1080 |
Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1082 |
return BfsWizard< |
|
1081 |
return BfsWizard<SetPredMapBase<T> >(*this); |
|
1083 | 1082 |
} |
1084 | 1083 |
|
1085 | 1084 |
template<class T> |
1086 |
struct |
|
1085 |
struct SetReachedMapBase : public Base { |
|
1087 | 1086 |
typedef T ReachedMap; |
1088 | 1087 |
static ReachedMap *createReachedMap(const Digraph &) { return 0; }; |
1089 |
|
|
1088 |
SetReachedMapBase(const TR &b) : TR(b) {} |
|
1090 | 1089 |
}; |
1091 | 1090 |
///\brief \ref named-templ-param "Named parameter" |
1092 | 1091 |
///for setting \ref ReachedMap object. |
1093 | 1092 |
/// |
1094 | 1093 |
/// \ref named-templ-param "Named parameter" |
1095 | 1094 |
///for setting \ref ReachedMap object. |
1096 | 1095 |
template<class T> |
1097 |
BfsWizard< |
|
1096 |
BfsWizard<SetReachedMapBase<T> > reachedMap(const T &t) |
|
1098 | 1097 |
{ |
1099 | 1098 |
Base::_reached=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1100 |
return BfsWizard< |
|
1099 |
return BfsWizard<SetReachedMapBase<T> >(*this); |
|
1101 | 1100 |
} |
1102 | 1101 |
|
1103 | 1102 |
template<class T> |
1104 |
struct |
|
1103 |
struct SetProcessedMapBase : public Base { |
|
1105 | 1104 |
typedef T ProcessedMap; |
1106 | 1105 |
static ProcessedMap *createProcessedMap(const Digraph &) { return 0; }; |
1107 |
|
|
1106 |
SetProcessedMapBase(const TR &b) : TR(b) {} |
|
1108 | 1107 |
}; |
1109 | 1108 |
///\brief \ref named-templ-param "Named parameter" |
1110 | 1109 |
///for setting \ref ProcessedMap object. |
1111 | 1110 |
/// |
1112 | 1111 |
/// \ref named-templ-param "Named parameter" |
1113 | 1112 |
///for setting \ref ProcessedMap object. |
1114 | 1113 |
template<class T> |
1115 |
BfsWizard< |
|
1114 |
BfsWizard<SetProcessedMapBase<T> > processedMap(const T &t) |
|
1116 | 1115 |
{ |
1117 | 1116 |
Base::_processed=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1118 |
return BfsWizard< |
|
1117 |
return BfsWizard<SetProcessedMapBase<T> >(*this); |
|
1119 | 1118 |
} |
1120 | 1119 |
|
1121 | 1120 |
template<class T> |
1122 |
struct |
|
1121 |
struct SetDistMapBase : public Base { |
|
1123 | 1122 |
typedef T DistMap; |
1124 | 1123 |
static DistMap *createDistMap(const Digraph &) { return 0; }; |
1125 |
|
|
1124 |
SetDistMapBase(const TR &b) : TR(b) {} |
|
1126 | 1125 |
}; |
1127 | 1126 |
///\brief \ref named-templ-param "Named parameter" |
1128 | 1127 |
///for setting \ref DistMap object. |
1129 | 1128 |
/// |
1130 | 1129 |
/// \ref named-templ-param "Named parameter" |
1131 | 1130 |
///for setting \ref DistMap object. |
1132 | 1131 |
template<class T> |
1133 |
BfsWizard< |
|
1132 |
BfsWizard<SetDistMapBase<T> > distMap(const T &t) |
|
1134 | 1133 |
{ |
1135 | 1134 |
Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1136 |
return BfsWizard< |
|
1135 |
return BfsWizard<SetDistMapBase<T> >(*this); |
|
1137 | 1136 |
} |
1138 | 1137 |
|
1139 | 1138 |
}; |
1140 | 1139 |
|
1141 | 1140 |
///Function type interface for Bfs algorithm. |
1142 | 1141 |
|
1143 | 1142 |
/// \ingroup search |
1144 | 1143 |
///Function type interface for Bfs algorithm. |
1145 | 1144 |
/// |
1146 | 1145 |
///This function also has several |
1147 | 1146 |
///\ref named-templ-func-param "named parameters", |
1148 | 1147 |
///they are declared as the members of class \ref BfsWizard. |
1149 | 1148 |
///The following |
1150 | 1149 |
///example shows how to use these parameters. |
1151 | 1150 |
///\code |
1152 | 1151 |
/// bfs(g,source).predMap(preds).run(); |
1153 | 1152 |
///\endcode |
1154 | 1153 |
///\warning Don't forget to put the \ref BfsWizard::run() "run()" |
1155 | 1154 |
///to the end of the parameter list. |
1156 | 1155 |
///\sa BfsWizard |
1157 | 1156 |
///\sa Bfs |
1158 | 1157 |
template<class GR> |
1159 | 1158 |
BfsWizard<BfsWizardBase<GR> > |
1160 | 1159 |
bfs(const GR &g,typename GR::Node s=INVALID) |
1161 | 1160 |
{ |
1162 | 1161 |
return BfsWizard<BfsWizardBase<GR> >(g,s); |
1163 | 1162 |
} |
1164 | 1163 |
|
1165 | 1164 |
#ifdef DOXYGEN |
1166 | 1165 |
/// \brief Visitor class for BFS. |
1167 | 1166 |
/// |
1168 | 1167 |
/// This class defines the interface of the BfsVisit events, and |
1169 | 1168 |
/// it could be the base of a real visitor class. |
1170 | 1169 |
template <typename _Digraph> |
1171 | 1170 |
struct BfsVisitor { |
1172 | 1171 |
typedef _Digraph Digraph; |
1173 | 1172 |
typedef typename Digraph::Arc Arc; |
1174 | 1173 |
typedef typename Digraph::Node Node; |
1175 | 1174 |
/// \brief Called for the source node(s) of the BFS. |
1176 | 1175 |
/// |
1177 | 1176 |
/// This function is called for the source node(s) of the BFS. |
1178 | 1177 |
void start(const Node& node) {} |
1179 | 1178 |
/// \brief Called when a node is reached first time. |
1180 | 1179 |
/// |
1181 | 1180 |
/// This function is called when a node is reached first time. |
1182 | 1181 |
void reach(const Node& node) {} |
1183 | 1182 |
/// \brief Called when a node is processed. |
1184 | 1183 |
/// |
1185 | 1184 |
/// This function is called when a node is processed. |
1186 | 1185 |
void process(const Node& node) {} |
1187 | 1186 |
/// \brief Called when an arc reaches a new node. |
1188 | 1187 |
/// |
1189 | 1188 |
/// This function is called when the BFS finds an arc whose target node |
1190 | 1189 |
/// is not reached yet. |
1191 | 1190 |
void discover(const Arc& arc) {} |
1192 | 1191 |
/// \brief Called when an arc is examined but its target node is |
1193 | 1192 |
/// already discovered. |
1194 | 1193 |
/// |
1195 | 1194 |
/// This function is called when an arc is examined but its target node is |
1196 | 1195 |
/// already discovered. |
1197 | 1196 |
void examine(const Arc& arc) {} |
1198 | 1197 |
}; |
1199 | 1198 |
#else |
1200 | 1199 |
template <typename _Digraph> |
1201 | 1200 |
struct BfsVisitor { |
1202 | 1201 |
typedef _Digraph Digraph; |
1203 | 1202 |
typedef typename Digraph::Arc Arc; |
1204 | 1203 |
typedef typename Digraph::Node Node; |
1205 | 1204 |
void start(const Node&) {} |
1206 | 1205 |
void reach(const Node&) {} |
1207 | 1206 |
void process(const Node&) {} |
1208 | 1207 |
void discover(const Arc&) {} |
1209 | 1208 |
void examine(const Arc&) {} |
1210 | 1209 |
|
1211 | 1210 |
template <typename _Visitor> |
1212 | 1211 |
struct Constraints { |
1213 | 1212 |
void constraints() { |
1214 | 1213 |
Arc arc; |
1215 | 1214 |
Node node; |
1216 | 1215 |
visitor.start(node); |
1217 | 1216 |
visitor.reach(node); |
1218 | 1217 |
visitor.process(node); |
1219 | 1218 |
visitor.discover(arc); |
1220 | 1219 |
visitor.examine(arc); |
1221 | 1220 |
} |
1222 | 1221 |
_Visitor& visitor; |
1223 | 1222 |
}; |
1224 | 1223 |
}; |
1225 | 1224 |
#endif |
1226 | 1225 |
|
1227 | 1226 |
/// \brief Default traits class of BfsVisit class. |
1228 | 1227 |
/// |
1229 | 1228 |
/// Default traits class of BfsVisit class. |
1230 | 1229 |
/// \tparam _Digraph The type of the digraph the algorithm runs on. |
1231 | 1230 |
template<class _Digraph> |
1232 | 1231 |
struct BfsVisitDefaultTraits { |
1233 | 1232 |
|
1234 | 1233 |
/// \brief The type of the digraph the algorithm runs on. |
1235 | 1234 |
typedef _Digraph Digraph; |
1236 | 1235 |
|
1237 | 1236 |
/// \brief The type of the map that indicates which nodes are reached. |
1238 | 1237 |
/// |
1239 | 1238 |
/// The type of the map that indicates which nodes are reached. |
1240 | 1239 |
/// It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept. |
1241 | 1240 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
1242 | 1241 |
|
1243 | 1242 |
/// \brief Instantiates a \ref ReachedMap. |
1244 | 1243 |
/// |
1245 | 1244 |
/// This function instantiates a \ref ReachedMap. |
1246 | 1245 |
/// \param digraph is the digraph, to which |
1247 | 1246 |
/// we would like to define the \ref ReachedMap. |
1248 | 1247 |
static ReachedMap *createReachedMap(const Digraph &digraph) { |
1249 | 1248 |
return new ReachedMap(digraph); |
1250 | 1249 |
} |
1251 | 1250 |
|
1252 | 1251 |
}; |
1253 | 1252 |
|
1254 | 1253 |
/// \ingroup search |
1255 | 1254 |
/// |
1256 | 1255 |
/// \brief %BFS algorithm class with visitor interface. |
1257 | 1256 |
/// |
1258 | 1257 |
/// This class provides an efficient implementation of the %BFS algorithm |
1259 | 1258 |
/// with visitor interface. |
1260 | 1259 |
/// |
1261 | 1260 |
/// The %BfsVisit class provides an alternative interface to the Bfs |
1262 | 1261 |
/// class. It works with callback mechanism, the BfsVisit object calls |
1263 | 1262 |
/// the member functions of the \c Visitor class on every BFS event. |
1264 | 1263 |
/// |
1265 | 1264 |
/// This interface of the BFS algorithm should be used in special cases |
1266 | 1265 |
/// when extra actions have to be performed in connection with certain |
1267 | 1266 |
/// events of the BFS algorithm. Otherwise consider to use Bfs or bfs() |
1268 | 1267 |
/// instead. |
1269 | 1268 |
/// |
1270 | 1269 |
/// \tparam _Digraph The type of the digraph the algorithm runs on. |
1271 | 1270 |
/// The default value is |
1272 | 1271 |
/// \ref ListDigraph. The value of _Digraph is not used directly by |
1273 | 1272 |
/// \ref BfsVisit, it is only passed to \ref BfsVisitDefaultTraits. |
1274 | 1273 |
/// \tparam _Visitor The Visitor type that is used by the algorithm. |
1275 | 1274 |
/// \ref BfsVisitor "BfsVisitor<_Digraph>" is an empty visitor, which |
1276 | 1275 |
/// does not observe the BFS events. If you want to observe the BFS |
1277 | 1276 |
/// events, you should implement your own visitor class. |
1278 | 1277 |
/// \tparam _Traits Traits class to set various data types used by the |
1279 | 1278 |
/// algorithm. The default traits class is |
1280 | 1279 |
/// \ref BfsVisitDefaultTraits "BfsVisitDefaultTraits<_Digraph>". |
1281 | 1280 |
/// See \ref BfsVisitDefaultTraits for the documentation of |
1282 | 1281 |
/// a BFS visit traits class. |
1283 | 1282 |
#ifdef DOXYGEN |
1284 | 1283 |
template <typename _Digraph, typename _Visitor, typename _Traits> |
1285 | 1284 |
#else |
1286 | 1285 |
template <typename _Digraph = ListDigraph, |
1287 | 1286 |
typename _Visitor = BfsVisitor<_Digraph>, |
1288 | 1287 |
typename _Traits = BfsDefaultTraits<_Digraph> > |
1289 | 1288 |
#endif |
1290 | 1289 |
class BfsVisit { |
1291 | 1290 |
public: |
1292 | 1291 |
|
1293 | 1292 |
/// \brief \ref Exception for uninitialized parameters. |
1294 | 1293 |
/// |
1295 | 1294 |
/// This error represents problems in the initialization |
1296 | 1295 |
/// of the parameters of the algorithm. |
1297 | 1296 |
class UninitializedParameter : public lemon::UninitializedParameter { |
1298 | 1297 |
public: |
1299 | 1298 |
virtual const char* what() const throw() |
1300 | 1299 |
{ |
1301 | 1300 |
return "lemon::BfsVisit::UninitializedParameter"; |
1302 | 1301 |
} |
1303 | 1302 |
}; |
1304 | 1303 |
|
1305 | 1304 |
///The traits class. |
1306 | 1305 |
typedef _Traits Traits; |
1307 | 1306 |
|
1308 | 1307 |
///The type of the digraph the algorithm runs on. |
1309 | 1308 |
typedef typename Traits::Digraph Digraph; |
1310 | 1309 |
|
1311 | 1310 |
///The visitor type used by the algorithm. |
1312 | 1311 |
typedef _Visitor Visitor; |
1313 | 1312 |
|
1314 | 1313 |
///The type of the map that indicates which nodes are reached. |
1315 | 1314 |
typedef typename Traits::ReachedMap ReachedMap; |
1316 | 1315 |
|
1317 | 1316 |
private: |
1318 | 1317 |
|
1319 | 1318 |
typedef typename Digraph::Node Node; |
1320 | 1319 |
typedef typename Digraph::NodeIt NodeIt; |
1321 | 1320 |
typedef typename Digraph::Arc Arc; |
1322 | 1321 |
typedef typename Digraph::OutArcIt OutArcIt; |
1323 | 1322 |
|
1324 | 1323 |
//Pointer to the underlying digraph. |
1325 | 1324 |
const Digraph *_digraph; |
1326 | 1325 |
//Pointer to the visitor object. |
1327 | 1326 |
Visitor *_visitor; |
1328 | 1327 |
//Pointer to the map of reached status of the nodes. |
1329 | 1328 |
ReachedMap *_reached; |
1330 | 1329 |
//Indicates if _reached is locally allocated (true) or not. |
1331 | 1330 |
bool local_reached; |
1332 | 1331 |
|
1333 | 1332 |
std::vector<typename Digraph::Node> _list; |
1334 | 1333 |
int _list_front, _list_back; |
1335 | 1334 |
|
1336 | 1335 |
///Creates the maps if necessary. |
1337 | 1336 |
///\todo Better memory allocation (instead of new). |
1338 | 1337 |
void create_maps() { |
1339 | 1338 |
if(!_reached) { |
1340 | 1339 |
local_reached = true; |
1341 | 1340 |
_reached = Traits::createReachedMap(*_digraph); |
1342 | 1341 |
} |
1343 | 1342 |
} |
1344 | 1343 |
|
1345 | 1344 |
protected: |
1346 | 1345 |
|
1347 | 1346 |
BfsVisit() {} |
1348 | 1347 |
|
1349 | 1348 |
public: |
1350 | 1349 |
|
1351 | 1350 |
typedef BfsVisit Create; |
1352 | 1351 |
|
1353 | 1352 |
/// \name Named template parameters |
1354 | 1353 |
|
1355 | 1354 |
///@{ |
1356 | 1355 |
template <class T> |
1357 |
struct |
|
1356 |
struct SetReachedMapTraits : public Traits { |
|
1358 | 1357 |
typedef T ReachedMap; |
1359 | 1358 |
static ReachedMap *createReachedMap(const Digraph &digraph) { |
1360 | 1359 |
throw UninitializedParameter(); |
1361 | 1360 |
} |
1362 | 1361 |
}; |
1363 | 1362 |
/// \brief \ref named-templ-param "Named parameter" for setting |
1364 | 1363 |
/// ReachedMap type. |
1365 | 1364 |
/// |
1366 | 1365 |
/// \ref named-templ-param "Named parameter" for setting ReachedMap type. |
1367 | 1366 |
template <class T> |
1368 |
struct DefReachedMap : public BfsVisit< Digraph, Visitor, |
|
1369 |
DefReachedMapTraits<T> > { |
|
1370 |
|
|
1367 |
struct SetReachedMap : public BfsVisit< Digraph, Visitor, |
|
1368 |
SetReachedMapTraits<T> > { |
|
1369 |
typedef BfsVisit< Digraph, Visitor, SetReachedMapTraits<T> > Create; |
|
1371 | 1370 |
}; |
1372 | 1371 |
///@} |
1373 | 1372 |
|
1374 | 1373 |
public: |
1375 | 1374 |
|
1376 | 1375 |
/// \brief Constructor. |
1377 | 1376 |
/// |
1378 | 1377 |
/// Constructor. |
1379 | 1378 |
/// |
1380 | 1379 |
/// \param digraph The digraph the algorithm runs on. |
1381 | 1380 |
/// \param visitor The visitor object of the algorithm. |
1382 | 1381 |
BfsVisit(const Digraph& digraph, Visitor& visitor) |
1383 | 1382 |
: _digraph(&digraph), _visitor(&visitor), |
1384 | 1383 |
_reached(0), local_reached(false) {} |
1385 | 1384 |
|
1386 | 1385 |
/// \brief Destructor. |
1387 | 1386 |
~BfsVisit() { |
1388 | 1387 |
if(local_reached) delete _reached; |
1389 | 1388 |
} |
1390 | 1389 |
|
1391 | 1390 |
/// \brief Sets the map that indicates which nodes are reached. |
1392 | 1391 |
/// |
1393 | 1392 |
/// Sets the map that indicates which nodes are reached. |
1394 | 1393 |
/// If you don't use this function before calling \ref run(), |
1395 | 1394 |
/// it will allocate one. The destructor deallocates this |
1396 | 1395 |
/// automatically allocated map, of course. |
1397 | 1396 |
/// \return <tt> (*this) </tt> |
1398 | 1397 |
BfsVisit &reachedMap(ReachedMap &m) { |
1399 | 1398 |
if(local_reached) { |
1400 | 1399 |
delete _reached; |
1401 | 1400 |
local_reached = false; |
1402 | 1401 |
} |
1403 | 1402 |
_reached = &m; |
1404 | 1403 |
return *this; |
1405 | 1404 |
} |
1406 | 1405 |
|
1407 | 1406 |
public: |
1408 | 1407 |
|
1409 | 1408 |
/// \name Execution control |
1410 | 1409 |
/// The simplest way to execute the algorithm is to use |
1411 | 1410 |
/// one of the member functions called \ref lemon::BfsVisit::run() |
1412 | 1411 |
/// "run()". |
1413 | 1412 |
/// \n |
1414 | 1413 |
/// If you need more control on the execution, first you must call |
1415 | 1414 |
/// \ref lemon::BfsVisit::init() "init()", then you can add several |
1416 | 1415 |
/// source nodes with \ref lemon::BfsVisit::addSource() "addSource()". |
1417 | 1416 |
/// Finally \ref lemon::BfsVisit::start() "start()" will perform the |
1418 | 1417 |
/// actual path computation. |
1419 | 1418 |
|
1420 | 1419 |
/// @{ |
1421 | 1420 |
|
1422 | 1421 |
/// \brief Initializes the internal data structures. |
1423 | 1422 |
/// |
1424 | 1423 |
/// Initializes the internal data structures. |
1425 | 1424 |
void init() { |
1426 | 1425 |
create_maps(); |
1427 | 1426 |
_list.resize(countNodes(*_digraph)); |
1428 | 1427 |
_list_front = _list_back = -1; |
1429 | 1428 |
for (NodeIt u(*_digraph) ; u != INVALID ; ++u) { |
1430 | 1429 |
_reached->set(u, false); |
1431 | 1430 |
} |
1432 | 1431 |
} |
1433 | 1432 |
|
1434 | 1433 |
/// \brief Adds a new source node. |
1435 | 1434 |
/// |
1436 | 1435 |
/// Adds a new source node to the set of nodes to be processed. |
1437 | 1436 |
void addSource(Node s) { |
1438 | 1437 |
if(!(*_reached)[s]) { |
1439 | 1438 |
_reached->set(s,true); |
1440 | 1439 |
_visitor->start(s); |
1441 | 1440 |
_visitor->reach(s); |
1442 | 1441 |
_list[++_list_back] = s; |
1443 | 1442 |
} |
1444 | 1443 |
} |
1445 | 1444 |
|
1446 | 1445 |
/// \brief Processes the next node. |
1447 | 1446 |
/// |
1448 | 1447 |
/// Processes the next node. |
1449 | 1448 |
/// |
1450 | 1449 |
/// \return The processed node. |
1451 | 1450 |
/// |
1452 | 1451 |
/// \pre The queue must not be empty. |
1453 | 1452 |
Node processNextNode() { |
1454 | 1453 |
Node n = _list[++_list_front]; |
1455 | 1454 |
_visitor->process(n); |
1456 | 1455 |
Arc e; |
1457 | 1456 |
for (_digraph->firstOut(e, n); e != INVALID; _digraph->nextOut(e)) { |
1458 | 1457 |
Node m = _digraph->target(e); |
1459 | 1458 |
if (!(*_reached)[m]) { |
1460 | 1459 |
_visitor->discover(e); |
1461 | 1460 |
_visitor->reach(m); |
1462 | 1461 |
_reached->set(m, true); |
1463 | 1462 |
_list[++_list_back] = m; |
1464 | 1463 |
} else { |
1465 | 1464 |
_visitor->examine(e); |
1466 | 1465 |
} |
1467 | 1466 |
} |
1468 | 1467 |
return n; |
1469 | 1468 |
} |
1470 | 1469 |
|
1471 | 1470 |
/// \brief Processes the next node. |
1472 | 1471 |
/// |
1473 | 1472 |
/// Processes the next node and checks if the given target node |
1474 | 1473 |
/// is reached. If the target node is reachable from the processed |
1475 | 1474 |
/// node, then the \c reach parameter will be set to \c true. |
1476 | 1475 |
/// |
1477 | 1476 |
/// \param target The target node. |
1478 | 1477 |
/// \retval reach Indicates if the target node is reached. |
1479 | 1478 |
/// It should be initially \c false. |
1480 | 1479 |
/// |
1481 | 1480 |
/// \return The processed node. |
1482 | 1481 |
/// |
1483 | 1482 |
/// \pre The queue must not be empty. |
1484 | 1483 |
Node processNextNode(Node target, bool& reach) { |
1485 | 1484 |
Node n = _list[++_list_front]; |
1486 | 1485 |
_visitor->process(n); |
1487 | 1486 |
Arc e; |
1488 | 1487 |
for (_digraph->firstOut(e, n); e != INVALID; _digraph->nextOut(e)) { |
1489 | 1488 |
Node m = _digraph->target(e); |
1490 | 1489 |
if (!(*_reached)[m]) { |
1491 | 1490 |
_visitor->discover(e); |
1492 | 1491 |
_visitor->reach(m); |
1493 | 1492 |
_reached->set(m, true); |
1494 | 1493 |
_list[++_list_back] = m; |
1495 | 1494 |
reach = reach || (target == m); |
1496 | 1495 |
} else { |
1497 | 1496 |
_visitor->examine(e); |
1498 | 1497 |
} |
1499 | 1498 |
} |
1500 | 1499 |
return n; |
1501 | 1500 |
} |
1502 | 1501 |
|
1503 | 1502 |
/// \brief Processes the next node. |
1504 | 1503 |
/// |
1505 | 1504 |
/// Processes the next node and checks if at least one of reached |
1506 | 1505 |
/// nodes has \c true value in the \c nm node map. If one node |
1507 | 1506 |
/// with \c true value is reachable from the processed node, then the |
1508 | 1507 |
/// \c rnode parameter will be set to the first of such nodes. |
1509 | 1508 |
/// |
1510 | 1509 |
/// \param nm A \c bool (or convertible) node map that indicates the |
1511 | 1510 |
/// possible targets. |
1512 | 1511 |
/// \retval rnode The reached target node. |
1513 | 1512 |
/// It should be initially \c INVALID. |
1514 | 1513 |
/// |
1515 | 1514 |
/// \return The processed node. |
1516 | 1515 |
/// |
1517 | 1516 |
/// \pre The queue must not be empty. |
1518 | 1517 |
template <typename NM> |
1519 | 1518 |
Node processNextNode(const NM& nm, Node& rnode) { |
1520 | 1519 |
Node n = _list[++_list_front]; |
1521 | 1520 |
_visitor->process(n); |
1522 | 1521 |
Arc e; |
1523 | 1522 |
for (_digraph->firstOut(e, n); e != INVALID; _digraph->nextOut(e)) { |
1524 | 1523 |
Node m = _digraph->target(e); |
1525 | 1524 |
if (!(*_reached)[m]) { |
1526 | 1525 |
_visitor->discover(e); |
1527 | 1526 |
_visitor->reach(m); |
1528 | 1527 |
_reached->set(m, true); |
1529 | 1528 |
_list[++_list_back] = m; |
1530 | 1529 |
if (nm[m] && rnode == INVALID) rnode = m; |
1531 | 1530 |
} else { |
1532 | 1531 |
_visitor->examine(e); |
1533 | 1532 |
} |
1534 | 1533 |
} |
1535 | 1534 |
return n; |
1536 | 1535 |
} |
1537 | 1536 |
|
1538 | 1537 |
/// \brief The next node to be processed. |
1539 | 1538 |
/// |
1540 | 1539 |
/// Returns the next node to be processed or \c INVALID if the queue |
1541 | 1540 |
/// is empty. |
1542 | 1541 |
Node nextNode() const { |
1543 | 1542 |
return _list_front != _list_back ? _list[_list_front + 1] : INVALID; |
1544 | 1543 |
} |
1545 | 1544 |
|
1546 | 1545 |
/// \brief Returns \c false if there are nodes |
1547 | 1546 |
/// to be processed. |
1548 | 1547 |
/// |
1549 | 1548 |
/// Returns \c false if there are nodes |
1550 | 1549 |
/// to be processed in the queue. |
1551 | 1550 |
bool emptyQueue() const { return _list_front == _list_back; } |
1552 | 1551 |
|
1553 | 1552 |
/// \brief Returns the number of the nodes to be processed. |
1554 | 1553 |
/// |
1555 | 1554 |
/// Returns the number of the nodes to be processed in the queue. |
1556 | 1555 |
int queueSize() const { return _list_back - _list_front; } |
1557 | 1556 |
|
1558 | 1557 |
/// \brief Executes the algorithm. |
1559 | 1558 |
/// |
1560 | 1559 |
/// Executes the algorithm. |
1561 | 1560 |
/// |
1562 | 1561 |
/// This method runs the %BFS algorithm from the root node(s) |
1563 | 1562 |
/// in order to compute the shortest path to each node. |
1564 | 1563 |
/// |
1565 | 1564 |
/// The algorithm computes |
1566 | 1565 |
/// - the shortest path tree (forest), |
1567 | 1566 |
/// - the distance of each node from the root(s). |
1568 | 1567 |
/// |
1569 | 1568 |
/// \pre init() must be called and at least one root node should be added |
1570 | 1569 |
/// with addSource() before using this function. |
1571 | 1570 |
/// |
1572 | 1571 |
/// \note <tt>b.start()</tt> is just a shortcut of the following code. |
1573 | 1572 |
/// \code |
1574 | 1573 |
/// while ( !b.emptyQueue() ) { |
1575 | 1574 |
/// b.processNextNode(); |
1576 | 1575 |
/// } |
1577 | 1576 |
/// \endcode |
1578 | 1577 |
void start() { |
1579 | 1578 |
while ( !emptyQueue() ) processNextNode(); |
1580 | 1579 |
} |
1581 | 1580 |
|
1582 | 1581 |
/// \brief Executes the algorithm until the given target node is reached. |
1583 | 1582 |
/// |
1584 | 1583 |
/// Executes the algorithm until the given target node is reached. |
1585 | 1584 |
/// |
1586 | 1585 |
/// This method runs the %BFS algorithm from the root node(s) |
1587 | 1586 |
/// in order to compute the shortest path to \c dest. |
1588 | 1587 |
/// |
1589 | 1588 |
/// The algorithm computes |
1590 | 1589 |
/// - the shortest path to \c dest, |
1591 | 1590 |
/// - the distance of \c dest from the root(s). |
1592 | 1591 |
/// |
1593 | 1592 |
/// \pre init() must be called and at least one root node should be |
1594 | 1593 |
/// added with addSource() before using this function. |
1595 | 1594 |
/// |
1596 | 1595 |
/// \note <tt>b.start(t)</tt> is just a shortcut of the following code. |
1597 | 1596 |
/// \code |
1598 | 1597 |
/// bool reach = false; |
1599 | 1598 |
/// while ( !b.emptyQueue() && !reach ) { |
1600 | 1599 |
/// b.processNextNode(t, reach); |
1601 | 1600 |
/// } |
1602 | 1601 |
/// \endcode |
1603 | 1602 |
void start(Node dest) { |
1604 | 1603 |
bool reach = false; |
1605 | 1604 |
while ( !emptyQueue() && !reach ) processNextNode(dest, reach); |
1606 | 1605 |
} |
1607 | 1606 |
|
1608 | 1607 |
/// \brief Executes the algorithm until a condition is met. |
1609 | 1608 |
/// |
1610 | 1609 |
/// Executes the algorithm until a condition is met. |
1611 | 1610 |
/// |
1612 | 1611 |
/// This method runs the %BFS algorithm from the root node(s) in |
1613 | 1612 |
/// order to compute the shortest path to a node \c v with |
1614 | 1613 |
/// <tt>nm[v]</tt> true, if such a node can be found. |
1615 | 1614 |
/// |
1616 | 1615 |
/// \param nm must be a bool (or convertible) node map. The |
1617 | 1616 |
/// algorithm will stop when it reaches a node \c v with |
1618 | 1617 |
/// <tt>nm[v]</tt> true. |
1619 | 1618 |
/// |
1620 | 1619 |
/// \return The reached node \c v with <tt>nm[v]</tt> true or |
1621 | 1620 |
/// \c INVALID if no such node was found. |
1622 | 1621 |
/// |
1623 | 1622 |
/// \pre init() must be called and at least one root node should be |
1624 | 1623 |
/// added with addSource() before using this function. |
1625 | 1624 |
/// |
1626 | 1625 |
/// \note <tt>b.start(nm)</tt> is just a shortcut of the following code. |
1 | 1 |
/* -*- mode: C++; indent-tabs-mode: nil; -*- |
2 | 2 |
* |
3 | 3 |
* This file is a part of LEMON, a generic C++ optimization library. |
4 | 4 |
* |
5 | 5 |
* Copyright (C) 2003-2008 |
6 | 6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
7 | 7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
8 | 8 |
* |
9 | 9 |
* Permission to use, modify and distribute this software is granted |
10 | 10 |
* provided that this copyright notice appears in all copies. For |
11 | 11 |
* precise terms see the accompanying LICENSE file. |
12 | 12 |
* |
13 | 13 |
* This software is provided "AS IS" with no warranty of any kind, |
14 | 14 |
* express or implied, and with no claim as to its suitability for any |
15 | 15 |
* purpose. |
16 | 16 |
* |
17 | 17 |
*/ |
18 | 18 |
|
19 | 19 |
#ifndef LEMON_BITS_BASE_EXTENDER_H |
20 | 20 |
#define LEMON_BITS_BASE_EXTENDER_H |
21 | 21 |
|
22 | 22 |
#include <lemon/core.h> |
23 | 23 |
#include <lemon/error.h> |
24 | 24 |
|
25 | 25 |
#include <lemon/bits/map_extender.h> |
26 | 26 |
#include <lemon/bits/default_map.h> |
27 | 27 |
|
28 | 28 |
#include <lemon/concept_check.h> |
29 | 29 |
#include <lemon/concepts/maps.h> |
30 | 30 |
|
31 | 31 |
///\ingroup digraphbits |
32 | 32 |
///\file |
33 | 33 |
///\brief Extenders for the digraph types |
34 | 34 |
namespace lemon { |
35 | 35 |
|
36 | 36 |
/// \ingroup digraphbits |
37 | 37 |
/// |
38 | 38 |
/// \brief BaseDigraph to BaseGraph extender |
39 | 39 |
template <typename Base> |
40 | 40 |
class UndirDigraphExtender : public Base { |
41 | 41 |
|
42 | 42 |
public: |
43 | 43 |
|
44 | 44 |
typedef Base Parent; |
45 | 45 |
typedef typename Parent::Arc Edge; |
46 | 46 |
typedef typename Parent::Node Node; |
47 | 47 |
|
48 | 48 |
typedef True UndirectedTag; |
49 | 49 |
|
50 | 50 |
class Arc : public Edge { |
51 | 51 |
friend class UndirDigraphExtender; |
52 | 52 |
|
53 | 53 |
protected: |
54 | 54 |
bool forward; |
55 | 55 |
|
56 | 56 |
Arc(const Edge &ue, bool _forward) : |
57 | 57 |
Edge(ue), forward(_forward) {} |
58 | 58 |
|
59 | 59 |
public: |
60 | 60 |
Arc() {} |
61 | 61 |
|
62 |
// |
|
62 |
// Invalid arc constructor |
|
63 | 63 |
Arc(Invalid i) : Edge(i), forward(true) {} |
64 | 64 |
|
65 | 65 |
bool operator==(const Arc &that) const { |
66 | 66 |
return forward==that.forward && Edge(*this)==Edge(that); |
67 | 67 |
} |
68 | 68 |
bool operator!=(const Arc &that) const { |
69 | 69 |
return forward!=that.forward || Edge(*this)!=Edge(that); |
70 | 70 |
} |
71 | 71 |
bool operator<(const Arc &that) const { |
72 | 72 |
return forward<that.forward || |
73 | 73 |
(!(that.forward<forward) && Edge(*this)<Edge(that)); |
74 | 74 |
} |
75 | 75 |
}; |
76 | 76 |
|
77 |
/// First node of the edge |
|
78 |
Node u(const Edge &e) const { |
|
79 |
return Parent::source(e); |
|
80 |
} |
|
77 | 81 |
|
78 |
|
|
79 |
using Parent::source; |
|
80 |
|
|
81 |
/// Source of the given Arc. |
|
82 |
/// Source of the given arc |
|
82 | 83 |
Node source(const Arc &e) const { |
83 | 84 |
return e.forward ? Parent::source(e) : Parent::target(e); |
84 | 85 |
} |
85 | 86 |
|
86 |
|
|
87 |
/// Second node of the edge |
|
88 |
Node v(const Edge &e) const { |
|
89 |
return Parent::target(e); |
|
90 |
} |
|
87 | 91 |
|
88 |
/// Target of the given |
|
92 |
/// Target of the given arc |
|
89 | 93 |
Node target(const Arc &e) const { |
90 | 94 |
return e.forward ? Parent::target(e) : Parent::source(e); |
91 | 95 |
} |
92 | 96 |
|
93 | 97 |
/// \brief Directed arc from an edge. |
94 | 98 |
/// |
95 |
/// Returns a directed arc corresponding to the specified Edge. |
|
96 |
/// If the given bool is true the given edge and the |
|
97 |
/// returned arc have the same source node. |
|
98 |
static Arc direct(const Edge &ue, bool d) { |
|
99 |
|
|
99 |
/// Returns a directed arc corresponding to the specified edge. |
|
100 |
/// If the given bool is true, the first node of the given edge and |
|
101 |
/// the source node of the returned arc are the same. |
|
102 |
static Arc direct(const Edge &e, bool d) { |
|
103 |
return Arc(e, d); |
|
100 | 104 |
} |
101 | 105 |
|
102 |
/// Returns whether the given directed arc is same orientation as the |
|
103 |
/// corresponding edge. |
|
106 |
/// Returns whether the given directed arc has the same orientation |
|
107 |
/// as the corresponding edge. |
|
104 | 108 |
/// |
105 | 109 |
/// \todo reference to the corresponding point of the undirected digraph |
106 | 110 |
/// concept. "What does the direction of an edge mean?" |
107 |
static bool direction(const Arc &e) { return e.forward; } |
|
108 |
|
|
111 |
static bool direction(const Arc &a) { return a.forward; } |
|
109 | 112 |
|
110 | 113 |
using Parent::first; |
111 | 114 |
using Parent::next; |
112 | 115 |
|
113 | 116 |
void first(Arc &e) const { |
114 | 117 |
Parent::first(e); |
115 | 118 |
e.forward=true; |
116 | 119 |
} |
117 | 120 |
|
118 | 121 |
void next(Arc &e) const { |
119 | 122 |
if( e.forward ) { |
120 | 123 |
e.forward = false; |
121 | 124 |
} |
122 | 125 |
else { |
123 | 126 |
Parent::next(e); |
124 | 127 |
e.forward = true; |
125 | 128 |
} |
126 | 129 |
} |
127 | 130 |
|
128 | 131 |
void firstOut(Arc &e, const Node &n) const { |
129 | 132 |
Parent::firstIn(e,n); |
130 | 133 |
if( Edge(e) != INVALID ) { |
131 | 134 |
e.forward = false; |
132 | 135 |
} |
133 | 136 |
else { |
134 | 137 |
Parent::firstOut(e,n); |
135 | 138 |
e.forward = true; |
136 | 139 |
} |
137 | 140 |
} |
138 | 141 |
void nextOut(Arc &e) const { |
139 | 142 |
if( ! e.forward ) { |
140 | 143 |
Node n = Parent::target(e); |
141 | 144 |
Parent::nextIn(e); |
142 | 145 |
if( Edge(e) == INVALID ) { |
143 | 146 |
Parent::firstOut(e, n); |
144 | 147 |
e.forward = true; |
145 | 148 |
} |
146 | 149 |
} |
147 | 150 |
else { |
148 | 151 |
Parent::nextOut(e); |
149 | 152 |
} |
150 | 153 |
} |
151 | 154 |
|
152 | 155 |
void firstIn(Arc &e, const Node &n) const { |
153 | 156 |
Parent::firstOut(e,n); |
154 | 157 |
if( Edge(e) != INVALID ) { |
155 | 158 |
e.forward = false; |
156 | 159 |
} |
157 | 160 |
else { |
158 | 161 |
Parent::firstIn(e,n); |
159 | 162 |
e.forward = true; |
160 | 163 |
} |
161 | 164 |
} |
162 | 165 |
void nextIn(Arc &e) const { |
163 | 166 |
if( ! e.forward ) { |
164 | 167 |
Node n = Parent::source(e); |
165 | 168 |
Parent::nextOut(e); |
166 | 169 |
if( Edge(e) == INVALID ) { |
167 | 170 |
Parent::firstIn(e, n); |
168 | 171 |
e.forward = true; |
169 | 172 |
} |
170 | 173 |
} |
171 | 174 |
else { |
172 | 175 |
Parent::nextIn(e); |
173 | 176 |
} |
174 | 177 |
} |
175 | 178 |
|
176 | 179 |
void firstInc(Edge &e, bool &d, const Node &n) const { |
177 | 180 |
d = true; |
178 | 181 |
Parent::firstOut(e, n); |
179 | 182 |
if (e != INVALID) return; |
180 | 183 |
d = false; |
181 | 184 |
Parent::firstIn(e, n); |
182 | 185 |
} |
183 | 186 |
|
184 | 187 |
void nextInc(Edge &e, bool &d) const { |
185 | 188 |
if (d) { |
186 | 189 |
Node s = Parent::source(e); |
187 | 190 |
Parent::nextOut(e); |
188 | 191 |
if (e != INVALID) return; |
189 | 192 |
d = false; |
190 | 193 |
Parent::firstIn(e, s); |
191 | 194 |
} else { |
192 | 195 |
Parent::nextIn(e); |
193 | 196 |
} |
194 | 197 |
} |
195 | 198 |
|
196 | 199 |
Node nodeFromId(int ix) const { |
197 | 200 |
return Parent::nodeFromId(ix); |
198 | 201 |
} |
199 | 202 |
|
200 | 203 |
Arc arcFromId(int ix) const { |
201 | 204 |
return direct(Parent::arcFromId(ix >> 1), bool(ix & 1)); |
202 | 205 |
} |
203 | 206 |
|
204 | 207 |
Edge edgeFromId(int ix) const { |
205 | 208 |
return Parent::arcFromId(ix); |
206 | 209 |
} |
207 | 210 |
|
208 | 211 |
int id(const Node &n) const { |
209 | 212 |
return Parent::id(n); |
210 | 213 |
} |
211 | 214 |
|
212 | 215 |
int id(const Edge &e) const { |
213 | 216 |
return Parent::id(e); |
214 | 217 |
} |
215 | 218 |
|
216 | 219 |
int id(const Arc &e) const { |
217 | 220 |
return 2 * Parent::id(e) + int(e.forward); |
218 | 221 |
} |
219 | 222 |
|
220 | 223 |
int maxNodeId() const { |
221 | 224 |
return Parent::maxNodeId(); |
222 | 225 |
} |
223 | 226 |
|
224 | 227 |
int maxArcId() const { |
225 | 228 |
return 2 * Parent::maxArcId() + 1; |
226 | 229 |
} |
227 | 230 |
|
228 | 231 |
int maxEdgeId() const { |
229 | 232 |
return Parent::maxArcId(); |
230 | 233 |
} |
231 | 234 |
|
232 |
|
|
233 | 235 |
int arcNum() const { |
234 | 236 |
return 2 * Parent::arcNum(); |
235 | 237 |
} |
236 | 238 |
|
237 | 239 |
int edgeNum() const { |
238 | 240 |
return Parent::arcNum(); |
239 | 241 |
} |
240 | 242 |
|
241 | 243 |
Arc findArc(Node s, Node t, Arc p = INVALID) const { |
242 | 244 |
if (p == INVALID) { |
243 | 245 |
Edge arc = Parent::findArc(s, t); |
244 | 246 |
if (arc != INVALID) return direct(arc, true); |
245 | 247 |
arc = Parent::findArc(t, s); |
246 | 248 |
if (arc != INVALID) return direct(arc, false); |
247 | 249 |
} else if (direction(p)) { |
248 | 250 |
Edge arc = Parent::findArc(s, t, p); |
249 | 251 |
if (arc != INVALID) return direct(arc, true); |
250 | 252 |
arc = Parent::findArc(t, s); |
251 | 253 |
if (arc != INVALID) return direct(arc, false); |
252 | 254 |
} else { |
253 | 255 |
Edge arc = Parent::findArc(t, s, p); |
254 | 256 |
if (arc != INVALID) return direct(arc, false); |
255 | 257 |
} |
256 | 258 |
return INVALID; |
257 | 259 |
} |
258 | 260 |
|
259 | 261 |
Edge findEdge(Node s, Node t, Edge p = INVALID) const { |
260 | 262 |
if (s != t) { |
261 | 263 |
if (p == INVALID) { |
262 | 264 |
Edge arc = Parent::findArc(s, t); |
263 | 265 |
if (arc != INVALID) return arc; |
264 | 266 |
arc = Parent::findArc(t, s); |
265 | 267 |
if (arc != INVALID) return arc; |
266 | 268 |
} else if (Parent::s(p) == s) { |
267 | 269 |
Edge arc = Parent::findArc(s, t, p); |
268 | 270 |
if (arc != INVALID) return arc; |
269 | 271 |
arc = Parent::findArc(t, s); |
270 | 272 |
if (arc != INVALID) return arc; |
271 | 273 |
} else { |
272 | 274 |
Edge arc = Parent::findArc(t, s, p); |
273 | 275 |
if (arc != INVALID) return arc; |
274 | 276 |
} |
275 | 277 |
} else { |
276 | 278 |
return Parent::findArc(s, t, p); |
277 | 279 |
} |
278 | 280 |
return INVALID; |
279 | 281 |
} |
280 | 282 |
}; |
281 | 283 |
|
282 | 284 |
template <typename Base> |
283 | 285 |
class BidirBpGraphExtender : public Base { |
284 | 286 |
public: |
285 | 287 |
typedef Base Parent; |
286 | 288 |
typedef BidirBpGraphExtender Digraph; |
287 | 289 |
|
288 | 290 |
typedef typename Parent::Node Node; |
289 | 291 |
typedef typename Parent::Edge Edge; |
290 | 292 |
|
291 | 293 |
|
292 | 294 |
using Parent::first; |
293 | 295 |
using Parent::next; |
294 | 296 |
|
295 | 297 |
using Parent::id; |
296 | 298 |
|
297 | 299 |
class Red : public Node { |
298 | 300 |
friend class BidirBpGraphExtender; |
299 | 301 |
public: |
300 | 302 |
Red() {} |
301 | 303 |
Red(const Node& node) : Node(node) { |
302 | 304 |
LEMON_ASSERT(Parent::red(node) || node == INVALID, |
303 | 305 |
typename Parent::NodeSetError()); |
304 | 306 |
} |
305 | 307 |
Red& operator=(const Node& node) { |
306 | 308 |
LEMON_ASSERT(Parent::red(node) || node == INVALID, |
307 | 309 |
typename Parent::NodeSetError()); |
308 | 310 |
Node::operator=(node); |
309 | 311 |
return *this; |
310 | 312 |
} |
311 | 313 |
Red(Invalid) : Node(INVALID) {} |
312 | 314 |
Red& operator=(Invalid) { |
313 | 315 |
Node::operator=(INVALID); |
314 | 316 |
return *this; |
315 | 317 |
} |
316 | 318 |
}; |
317 | 319 |
|
318 | 320 |
void first(Red& node) const { |
319 | 321 |
Parent::firstRed(static_cast<Node&>(node)); |
320 | 322 |
} |
321 | 323 |
void next(Red& node) const { |
322 | 324 |
Parent::nextRed(static_cast<Node&>(node)); |
323 | 325 |
} |
324 | 326 |
|
325 | 327 |
int id(const Red& node) const { |
326 | 328 |
return Parent::redId(node); |
327 | 329 |
} |
328 | 330 |
|
329 | 331 |
class Blue : public Node { |
330 | 332 |
friend class BidirBpGraphExtender; |
331 | 333 |
public: |
332 | 334 |
Blue() {} |
333 | 335 |
Blue(const Node& node) : Node(node) { |
334 | 336 |
LEMON_ASSERT(Parent::blue(node) || node == INVALID, |
335 | 337 |
typename Parent::NodeSetError()); |
336 | 338 |
} |
337 | 339 |
Blue& operator=(const Node& node) { |
338 | 340 |
LEMON_ASSERT(Parent::blue(node) || node == INVALID, |
339 | 341 |
typename Parent::NodeSetError()); |
340 | 342 |
Node::operator=(node); |
341 | 343 |
return *this; |
342 | 344 |
} |
343 | 345 |
Blue(Invalid) : Node(INVALID) {} |
344 | 346 |
Blue& operator=(Invalid) { |
345 | 347 |
Node::operator=(INVALID); |
346 | 348 |
return *this; |
347 | 349 |
} |
348 | 350 |
}; |
349 | 351 |
|
350 | 352 |
void first(Blue& node) const { |
351 | 353 |
Parent::firstBlue(static_cast<Node&>(node)); |
352 | 354 |
} |
353 | 355 |
void next(Blue& node) const { |
354 | 356 |
Parent::nextBlue(static_cast<Node&>(node)); |
355 | 357 |
} |
356 | 358 |
|
357 | 359 |
int id(const Blue& node) const { |
358 | 360 |
return Parent::redId(node); |
359 | 361 |
} |
360 | 362 |
|
361 | 363 |
Node source(const Edge& arc) const { |
362 | 364 |
return red(arc); |
363 | 365 |
} |
364 | 366 |
Node target(const Edge& arc) const { |
365 | 367 |
return blue(arc); |
366 | 368 |
} |
367 | 369 |
|
368 | 370 |
void firstInc(Edge& arc, bool& dir, const Node& node) const { |
369 | 371 |
if (Parent::red(node)) { |
370 | 372 |
Parent::firstFromRed(arc, node); |
371 | 373 |
dir = true; |
372 | 374 |
} else { |
373 | 375 |
Parent::firstFromBlue(arc, node); |
374 | 376 |
dir = static_cast<Edge&>(arc) == INVALID; |
375 | 377 |
} |
376 | 378 |
} |
377 | 379 |
void nextInc(Edge& arc, bool& dir) const { |
378 | 380 |
if (dir) { |
379 | 381 |
Parent::nextFromRed(arc); |
380 | 382 |
} else { |
381 | 383 |
Parent::nextFromBlue(arc); |
382 | 384 |
if (arc == INVALID) dir = true; |
383 | 385 |
} |
384 | 386 |
} |
385 | 387 |
|
386 | 388 |
class Arc : public Edge { |
387 | 389 |
friend class BidirBpGraphExtender; |
388 | 390 |
protected: |
389 | 391 |
bool forward; |
390 | 392 |
|
391 | 393 |
Arc(const Edge& arc, bool _forward) |
392 | 394 |
: Edge(arc), forward(_forward) {} |
393 | 395 |
|
394 | 396 |
public: |
395 | 397 |
Arc() {} |
396 | 398 |
Arc (Invalid) : Edge(INVALID), forward(true) {} |
397 | 399 |
bool operator==(const Arc& i) const { |
398 | 400 |
return Edge::operator==(i) && forward == i.forward; |
399 | 401 |
} |
400 | 402 |
bool operator!=(const Arc& i) const { |
401 | 403 |
return Edge::operator!=(i) || forward != i.forward; |
402 | 404 |
} |
403 | 405 |
bool operator<(const Arc& i) const { |
404 | 406 |
return Edge::operator<(i) || |
405 | 407 |
(!(i.forward<forward) && Edge(*this)<Edge(i)); |
406 | 408 |
} |
407 | 409 |
}; |
408 | 410 |
|
409 | 411 |
void first(Arc& arc) const { |
410 | 412 |
Parent::first(static_cast<Edge&>(arc)); |
411 | 413 |
arc.forward = true; |
412 | 414 |
} |
413 | 415 |
|
414 | 416 |
void next(Arc& arc) const { |
415 | 417 |
if (!arc.forward) { |
416 | 418 |
Parent::next(static_cast<Edge&>(arc)); |
417 | 419 |
} |
418 | 420 |
arc.forward = !arc.forward; |
419 | 421 |
} |
420 | 422 |
|
421 | 423 |
void firstOut(Arc& arc, const Node& node) const { |
422 | 424 |
if (Parent::red(node)) { |
423 | 425 |
Parent::firstFromRed(arc, node); |
424 | 426 |
arc.forward = true; |
425 | 427 |
} else { |
426 | 428 |
Parent::firstFromBlue(arc, node); |
427 | 429 |
arc.forward = static_cast<Edge&>(arc) == INVALID; |
428 | 430 |
} |
429 | 431 |
} |
430 | 432 |
void nextOut(Arc& arc) const { |
431 | 433 |
if (arc.forward) { |
432 | 434 |
Parent::nextFromRed(arc); |
433 | 435 |
} else { |
434 | 436 |
Parent::nextFromBlue(arc); |
435 | 437 |
arc.forward = static_cast<Edge&>(arc) == INVALID; |
436 | 438 |
} |
437 | 439 |
} |
438 | 440 |
|
439 | 441 |
void firstIn(Arc& arc, const Node& node) const { |
440 | 442 |
if (Parent::blue(node)) { |
441 | 443 |
Parent::firstFromBlue(arc, node); |
442 | 444 |
arc.forward = true; |
443 | 445 |
} else { |
444 | 446 |
Parent::firstFromRed(arc, node); |
445 | 447 |
arc.forward = static_cast<Edge&>(arc) == INVALID; |
446 | 448 |
} |
447 | 449 |
} |
448 | 450 |
void nextIn(Arc& arc) const { |
449 | 451 |
if (arc.forward) { |
450 | 452 |
Parent::nextFromBlue(arc); |
451 | 453 |
} else { |
452 | 454 |
Parent::nextFromRed(arc); |
453 | 455 |
arc.forward = static_cast<Edge&>(arc) == INVALID; |
454 | 456 |
} |
455 | 457 |
} |
456 | 458 |
|
457 | 459 |
Node source(const Arc& arc) const { |
458 | 460 |
return arc.forward ? Parent::red(arc) : Parent::blue(arc); |
459 | 461 |
} |
460 | 462 |
Node target(const Arc& arc) const { |
461 | 463 |
return arc.forward ? Parent::blue(arc) : Parent::red(arc); |
462 | 464 |
} |
463 | 465 |
|
464 | 466 |
int id(const Arc& arc) const { |
465 | 467 |
return (Parent::id(static_cast<const Edge&>(arc)) << 1) + |
466 | 468 |
(arc.forward ? 0 : 1); |
467 | 469 |
} |
468 | 470 |
Arc arcFromId(int ix) const { |
469 | 471 |
return Arc(Parent::fromEdgeId(ix >> 1), (ix & 1) == 0); |
470 | 472 |
} |
471 | 473 |
int maxArcId() const { |
472 | 474 |
return (Parent::maxEdgeId() << 1) + 1; |
473 | 475 |
} |
474 | 476 |
|
475 | 477 |
bool direction(const Arc& arc) const { |
476 | 478 |
return arc.forward; |
477 | 479 |
} |
478 | 480 |
|
479 | 481 |
Arc direct(const Edge& arc, bool dir) const { |
480 | 482 |
return Arc(arc, dir); |
481 | 483 |
} |
482 | 484 |
|
483 | 485 |
int arcNum() const { |
484 | 486 |
return 2 * Parent::edgeNum(); |
485 | 487 |
} |
486 | 488 |
|
487 | 489 |
int edgeNum() const { |
488 | 490 |
return Parent::edgeNum(); |
1 | 1 |
/* -*- mode: C++; indent-tabs-mode: nil; -*- |
2 | 2 |
* |
3 | 3 |
* This file is a part of LEMON, a generic C++ optimization library. |
4 | 4 |
* |
5 | 5 |
* Copyright (C) 2003-2008 |
6 | 6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
7 | 7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
8 | 8 |
* |
9 | 9 |
* Permission to use, modify and distribute this software is granted |
10 | 10 |
* provided that this copyright notice appears in all copies. For |
11 | 11 |
* precise terms see the accompanying LICENSE file. |
12 | 12 |
* |
13 | 13 |
* This software is provided "AS IS" with no warranty of any kind, |
14 | 14 |
* express or implied, and with no claim as to its suitability for any |
15 | 15 |
* purpose. |
16 | 16 |
* |
17 | 17 |
*/ |
18 | 18 |
|
19 | 19 |
#ifndef LEMON_DFS_H |
20 | 20 |
#define LEMON_DFS_H |
21 | 21 |
|
22 | 22 |
///\ingroup search |
23 | 23 |
///\file |
24 | 24 |
///\brief DFS algorithm. |
25 | 25 |
|
26 | 26 |
#include <lemon/list_graph.h> |
27 | 27 |
#include <lemon/bits/path_dump.h> |
28 | 28 |
#include <lemon/core.h> |
29 | 29 |
#include <lemon/error.h> |
30 | 30 |
#include <lemon/assert.h> |
31 | 31 |
#include <lemon/maps.h> |
32 | 32 |
|
33 | 33 |
namespace lemon { |
34 | 34 |
|
35 | 35 |
///Default traits class of Dfs class. |
36 | 36 |
|
37 | 37 |
///Default traits class of Dfs class. |
38 | 38 |
///\tparam GR Digraph type. |
39 | 39 |
template<class GR> |
40 | 40 |
struct DfsDefaultTraits |
41 | 41 |
{ |
42 | 42 |
///The type of the digraph the algorithm runs on. |
43 | 43 |
typedef GR Digraph; |
44 | 44 |
|
45 | 45 |
///\brief The type of the map that stores the predecessor |
46 | 46 |
///arcs of the %DFS paths. |
47 | 47 |
/// |
48 | 48 |
///The type of the map that stores the predecessor |
49 | 49 |
///arcs of the %DFS paths. |
50 | 50 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
51 | 51 |
typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap; |
52 | 52 |
///Instantiates a \ref PredMap. |
53 | 53 |
|
54 | 54 |
///This function instantiates a \ref PredMap. |
55 | 55 |
///\param g is the digraph, to which we would like to define the |
56 | 56 |
///\ref PredMap. |
57 | 57 |
///\todo The digraph alone may be insufficient to initialize |
58 | 58 |
static PredMap *createPredMap(const Digraph &g) |
59 | 59 |
{ |
60 | 60 |
return new PredMap(g); |
61 | 61 |
} |
62 | 62 |
|
63 | 63 |
///The type of the map that indicates which nodes are processed. |
64 | 64 |
|
65 | 65 |
///The type of the map that indicates which nodes are processed. |
66 | 66 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
67 | 67 |
///By default it is a NullMap. |
68 | 68 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
69 | 69 |
///Instantiates a \ref ProcessedMap. |
70 | 70 |
|
71 | 71 |
///This function instantiates a \ref ProcessedMap. |
72 | 72 |
///\param g is the digraph, to which |
73 | 73 |
///we would like to define the \ref ProcessedMap |
74 | 74 |
#ifdef DOXYGEN |
75 | 75 |
static ProcessedMap *createProcessedMap(const Digraph &g) |
76 | 76 |
#else |
77 | 77 |
static ProcessedMap *createProcessedMap(const Digraph &) |
78 | 78 |
#endif |
79 | 79 |
{ |
80 | 80 |
return new ProcessedMap(); |
81 | 81 |
} |
82 | 82 |
|
83 | 83 |
///The type of the map that indicates which nodes are reached. |
84 | 84 |
|
85 | 85 |
///The type of the map that indicates which nodes are reached. |
86 | 86 |
///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept. |
87 | 87 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
88 | 88 |
///Instantiates a \ref ReachedMap. |
89 | 89 |
|
90 | 90 |
///This function instantiates a \ref ReachedMap. |
91 | 91 |
///\param g is the digraph, to which |
92 | 92 |
///we would like to define the \ref ReachedMap. |
93 | 93 |
static ReachedMap *createReachedMap(const Digraph &g) |
94 | 94 |
{ |
95 | 95 |
return new ReachedMap(g); |
96 | 96 |
} |
97 | 97 |
|
98 | 98 |
///The type of the map that stores the distances of the nodes. |
99 | 99 |
|
100 | 100 |
///The type of the map that stores the distances of the nodes. |
101 | 101 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
102 | 102 |
typedef typename Digraph::template NodeMap<int> DistMap; |
103 | 103 |
///Instantiates a \ref DistMap. |
104 | 104 |
|
105 | 105 |
///This function instantiates a \ref DistMap. |
106 | 106 |
///\param g is the digraph, to which we would like to define the |
107 | 107 |
///\ref DistMap. |
108 | 108 |
static DistMap *createDistMap(const Digraph &g) |
109 | 109 |
{ |
110 | 110 |
return new DistMap(g); |
111 | 111 |
} |
112 | 112 |
}; |
113 | 113 |
|
114 | 114 |
///%DFS algorithm class. |
115 | 115 |
|
116 | 116 |
///\ingroup search |
117 | 117 |
///This class provides an efficient implementation of the %DFS algorithm. |
118 | 118 |
/// |
119 | 119 |
///There is also a \ref dfs() "function type interface" for the DFS |
120 | 120 |
///algorithm, which is convenient in the simplier cases and it can be |
121 | 121 |
///used easier. |
122 | 122 |
/// |
123 | 123 |
///\tparam GR The type of the digraph the algorithm runs on. |
124 | 124 |
///The default value is \ref ListDigraph. The value of GR is not used |
125 | 125 |
///directly by \ref Dfs, it is only passed to \ref DfsDefaultTraits. |
126 | 126 |
///\tparam TR Traits class to set various data types used by the algorithm. |
127 | 127 |
///The default traits class is |
128 | 128 |
///\ref DfsDefaultTraits "DfsDefaultTraits<GR>". |
129 | 129 |
///See \ref DfsDefaultTraits for the documentation of |
130 | 130 |
///a Dfs traits class. |
131 | 131 |
#ifdef DOXYGEN |
132 | 132 |
template <typename GR, |
133 | 133 |
typename TR> |
134 | 134 |
#else |
135 | 135 |
template <typename GR=ListDigraph, |
136 | 136 |
typename TR=DfsDefaultTraits<GR> > |
137 | 137 |
#endif |
138 | 138 |
class Dfs { |
139 | 139 |
public: |
140 | 140 |
///\ref Exception for uninitialized parameters. |
141 | 141 |
|
142 | 142 |
///This error represents problems in the initialization of the |
143 | 143 |
///parameters of the algorithm. |
144 | 144 |
class UninitializedParameter : public lemon::UninitializedParameter { |
145 | 145 |
public: |
146 | 146 |
virtual const char* what() const throw() { |
147 | 147 |
return "lemon::Dfs::UninitializedParameter"; |
148 | 148 |
} |
149 | 149 |
}; |
150 | 150 |
|
151 | 151 |
///The type of the digraph the algorithm runs on. |
152 | 152 |
typedef typename TR::Digraph Digraph; |
153 | 153 |
|
154 | 154 |
///\brief The type of the map that stores the predecessor arcs of the |
155 | 155 |
///DFS paths. |
156 | 156 |
typedef typename TR::PredMap PredMap; |
157 | 157 |
///The type of the map that stores the distances of the nodes. |
158 | 158 |
typedef typename TR::DistMap DistMap; |
159 | 159 |
///The type of the map that indicates which nodes are reached. |
160 | 160 |
typedef typename TR::ReachedMap ReachedMap; |
161 | 161 |
///The type of the map that indicates which nodes are processed. |
162 | 162 |
typedef typename TR::ProcessedMap ProcessedMap; |
163 | 163 |
///The type of the paths. |
164 | 164 |
typedef PredMapPath<Digraph, PredMap> Path; |
165 | 165 |
|
166 | 166 |
///The traits class. |
167 | 167 |
typedef TR Traits; |
168 | 168 |
|
169 | 169 |
private: |
170 | 170 |
|
171 | 171 |
typedef typename Digraph::Node Node; |
172 | 172 |
typedef typename Digraph::NodeIt NodeIt; |
173 | 173 |
typedef typename Digraph::Arc Arc; |
174 | 174 |
typedef typename Digraph::OutArcIt OutArcIt; |
175 | 175 |
|
176 | 176 |
//Pointer to the underlying digraph. |
177 | 177 |
const Digraph *G; |
178 | 178 |
//Pointer to the map of predecessor arcs. |
179 | 179 |
PredMap *_pred; |
180 | 180 |
//Indicates if _pred is locally allocated (true) or not. |
181 | 181 |
bool local_pred; |
182 | 182 |
//Pointer to the map of distances. |
183 | 183 |
DistMap *_dist; |
184 | 184 |
//Indicates if _dist is locally allocated (true) or not. |
185 | 185 |
bool local_dist; |
186 | 186 |
//Pointer to the map of reached status of the nodes. |
187 | 187 |
ReachedMap *_reached; |
188 | 188 |
//Indicates if _reached is locally allocated (true) or not. |
189 | 189 |
bool local_reached; |
190 | 190 |
//Pointer to the map of processed status of the nodes. |
191 | 191 |
ProcessedMap *_processed; |
192 | 192 |
//Indicates if _processed is locally allocated (true) or not. |
193 | 193 |
bool local_processed; |
194 | 194 |
|
195 | 195 |
std::vector<typename Digraph::OutArcIt> _stack; |
196 | 196 |
int _stack_head; |
197 | 197 |
|
198 | 198 |
///Creates the maps if necessary. |
199 | 199 |
///\todo Better memory allocation (instead of new). |
200 | 200 |
void create_maps() |
201 | 201 |
{ |
202 | 202 |
if(!_pred) { |
203 | 203 |
local_pred = true; |
204 | 204 |
_pred = Traits::createPredMap(*G); |
205 | 205 |
} |
206 | 206 |
if(!_dist) { |
207 | 207 |
local_dist = true; |
208 | 208 |
_dist = Traits::createDistMap(*G); |
209 | 209 |
} |
210 | 210 |
if(!_reached) { |
211 | 211 |
local_reached = true; |
212 | 212 |
_reached = Traits::createReachedMap(*G); |
213 | 213 |
} |
214 | 214 |
if(!_processed) { |
215 | 215 |
local_processed = true; |
216 | 216 |
_processed = Traits::createProcessedMap(*G); |
217 | 217 |
} |
218 | 218 |
} |
219 | 219 |
|
220 | 220 |
protected: |
221 | 221 |
|
222 | 222 |
Dfs() {} |
223 | 223 |
|
224 | 224 |
public: |
225 | 225 |
|
226 | 226 |
typedef Dfs Create; |
227 | 227 |
|
228 | 228 |
///\name Named template parameters |
229 | 229 |
|
230 | 230 |
///@{ |
231 | 231 |
|
232 | 232 |
template <class T> |
233 |
struct |
|
233 |
struct SetPredMapTraits : public Traits { |
|
234 | 234 |
typedef T PredMap; |
235 | 235 |
static PredMap *createPredMap(const Digraph &) |
236 | 236 |
{ |
237 | 237 |
throw UninitializedParameter(); |
238 | 238 |
} |
239 | 239 |
}; |
240 | 240 |
///\brief \ref named-templ-param "Named parameter" for setting |
241 | 241 |
///\ref PredMap type. |
242 | 242 |
/// |
243 | 243 |
///\ref named-templ-param "Named parameter" for setting |
244 | 244 |
///\ref PredMap type. |
245 | 245 |
template <class T> |
246 |
struct DefPredMap : public Dfs<Digraph, DefPredMapTraits<T> > { |
|
247 |
typedef Dfs<Digraph, DefPredMapTraits<T> > Create; |
|
246 |
struct SetPredMap : public Dfs<Digraph, SetPredMapTraits<T> > { |
|
247 |
typedef Dfs<Digraph, SetPredMapTraits<T> > Create; |
|
248 | 248 |
}; |
249 | 249 |
|
250 | 250 |
template <class T> |
251 |
struct |
|
251 |
struct SetDistMapTraits : public Traits { |
|
252 | 252 |
typedef T DistMap; |
253 | 253 |
static DistMap *createDistMap(const Digraph &) |
254 | 254 |
{ |
255 | 255 |
throw UninitializedParameter(); |
256 | 256 |
} |
257 | 257 |
}; |
258 | 258 |
///\brief \ref named-templ-param "Named parameter" for setting |
259 | 259 |
///\ref DistMap type. |
260 | 260 |
/// |
261 | 261 |
///\ref named-templ-param "Named parameter" for setting |
262 | 262 |
///\ref DistMap type. |
263 | 263 |
template <class T> |
264 |
struct DefDistMap : public Dfs< Digraph, DefDistMapTraits<T> > { |
|
265 |
typedef Dfs<Digraph, DefDistMapTraits<T> > Create; |
|
264 |
struct SetDistMap : public Dfs< Digraph, SetDistMapTraits<T> > { |
|
265 |
typedef Dfs<Digraph, SetDistMapTraits<T> > Create; |
|
266 | 266 |
}; |
267 | 267 |
|
268 | 268 |
template <class T> |
269 |
struct |
|
269 |
struct SetReachedMapTraits : public Traits { |
|
270 | 270 |
typedef T ReachedMap; |
271 | 271 |
static ReachedMap *createReachedMap(const Digraph &) |
272 | 272 |
{ |
273 | 273 |
throw UninitializedParameter(); |
274 | 274 |
} |
275 | 275 |
}; |
276 | 276 |
///\brief \ref named-templ-param "Named parameter" for setting |
277 | 277 |
///\ref ReachedMap type. |
278 | 278 |
/// |
279 | 279 |
///\ref named-templ-param "Named parameter" for setting |
280 | 280 |
///\ref ReachedMap type. |
281 | 281 |
template <class T> |
282 |
struct DefReachedMap : public Dfs< Digraph, DefReachedMapTraits<T> > { |
|
283 |
typedef Dfs< Digraph, DefReachedMapTraits<T> > Create; |
|
282 |
struct SetReachedMap : public Dfs< Digraph, SetReachedMapTraits<T> > { |
|
283 |
typedef Dfs< Digraph, SetReachedMapTraits<T> > Create; |
|
284 | 284 |
}; |
285 | 285 |
|
286 | 286 |
template <class T> |
287 |
struct |
|
287 |
struct SetProcessedMapTraits : public Traits { |
|
288 | 288 |
typedef T ProcessedMap; |
289 | 289 |
static ProcessedMap *createProcessedMap(const Digraph &) |
290 | 290 |
{ |
291 | 291 |
throw UninitializedParameter(); |
292 | 292 |
} |
293 | 293 |
}; |
294 | 294 |
///\brief \ref named-templ-param "Named parameter" for setting |
295 | 295 |
///\ref ProcessedMap type. |
296 | 296 |
/// |
297 | 297 |
///\ref named-templ-param "Named parameter" for setting |
298 | 298 |
///\ref ProcessedMap type. |
299 | 299 |
template <class T> |
300 |
struct DefProcessedMap : public Dfs< Digraph, DefProcessedMapTraits<T> > { |
|
301 |
typedef Dfs< Digraph, DefProcessedMapTraits<T> > Create; |
|
300 |
struct SetProcessedMap : public Dfs< Digraph, SetProcessedMapTraits<T> > { |
|
301 |
typedef Dfs< Digraph, SetProcessedMapTraits<T> > Create; |
|
302 | 302 |
}; |
303 | 303 |
|
304 |
struct |
|
304 |
struct SetStandardProcessedMapTraits : public Traits { |
|
305 | 305 |
typedef typename Digraph::template NodeMap<bool> ProcessedMap; |
306 | 306 |
static ProcessedMap *createProcessedMap(const Digraph &g) |
307 | 307 |
{ |
308 | 308 |
return new ProcessedMap(g); |
309 | 309 |
} |
310 | 310 |
}; |
311 | 311 |
///\brief \ref named-templ-param "Named parameter" for setting |
312 | 312 |
///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>. |
313 | 313 |
/// |
314 | 314 |
///\ref named-templ-param "Named parameter" for setting |
315 | 315 |
///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>. |
316 | 316 |
///If you don't set it explicitly, it will be automatically allocated. |
317 |
template <class T> |
|
318 |
struct DefProcessedMapToBeDefaultMap : |
|
319 |
public Dfs< Digraph, DefDigraphProcessedMapTraits> { |
|
320 |
typedef Dfs< Digraph, DefDigraphProcessedMapTraits> Create; |
|
317 |
struct SetStandardProcessedMap : |
|
318 |
public Dfs< Digraph, SetStandardProcessedMapTraits > { |
|
319 |
typedef Dfs< Digraph, SetStandardProcessedMapTraits > Create; |
|
321 | 320 |
}; |
322 | 321 |
|
323 | 322 |
///@} |
324 | 323 |
|
325 | 324 |
public: |
326 | 325 |
|
327 | 326 |
///Constructor. |
328 | 327 |
|
329 | 328 |
///Constructor. |
330 | 329 |
///\param g The digraph the algorithm runs on. |
331 | 330 |
Dfs(const Digraph &g) : |
332 | 331 |
G(&g), |
333 | 332 |
_pred(NULL), local_pred(false), |
334 | 333 |
_dist(NULL), local_dist(false), |
335 | 334 |
_reached(NULL), local_reached(false), |
336 | 335 |
_processed(NULL), local_processed(false) |
337 | 336 |
{ } |
338 | 337 |
|
339 | 338 |
///Destructor. |
340 | 339 |
~Dfs() |
341 | 340 |
{ |
342 | 341 |
if(local_pred) delete _pred; |
343 | 342 |
if(local_dist) delete _dist; |
344 | 343 |
if(local_reached) delete _reached; |
345 | 344 |
if(local_processed) delete _processed; |
346 | 345 |
} |
347 | 346 |
|
348 | 347 |
///Sets the map that stores the predecessor arcs. |
349 | 348 |
|
350 | 349 |
///Sets the map that stores the predecessor arcs. |
351 | 350 |
///If you don't use this function before calling \ref run(), |
352 | 351 |
///it will allocate one. The destructor deallocates this |
353 | 352 |
///automatically allocated map, of course. |
354 | 353 |
///\return <tt> (*this) </tt> |
355 | 354 |
Dfs &predMap(PredMap &m) |
356 | 355 |
{ |
357 | 356 |
if(local_pred) { |
358 | 357 |
delete _pred; |
359 | 358 |
local_pred=false; |
360 | 359 |
} |
361 | 360 |
_pred = &m; |
362 | 361 |
return *this; |
363 | 362 |
} |
364 | 363 |
|
365 | 364 |
///Sets the map that indicates which nodes are reached. |
366 | 365 |
|
367 | 366 |
///Sets the map that indicates which nodes are reached. |
368 | 367 |
///If you don't use this function before calling \ref run(), |
369 | 368 |
///it will allocate one. The destructor deallocates this |
370 | 369 |
///automatically allocated map, of course. |
371 | 370 |
///\return <tt> (*this) </tt> |
372 | 371 |
Dfs &reachedMap(ReachedMap &m) |
373 | 372 |
{ |
374 | 373 |
if(local_reached) { |
375 | 374 |
delete _reached; |
376 | 375 |
local_reached=false; |
377 | 376 |
} |
378 | 377 |
_reached = &m; |
379 | 378 |
return *this; |
380 | 379 |
} |
381 | 380 |
|
382 | 381 |
///Sets the map that indicates which nodes are processed. |
383 | 382 |
|
384 | 383 |
///Sets the map that indicates which nodes are processed. |
385 | 384 |
///If you don't use this function before calling \ref run(), |
386 | 385 |
///it will allocate one. The destructor deallocates this |
387 | 386 |
///automatically allocated map, of course. |
388 | 387 |
///\return <tt> (*this) </tt> |
389 | 388 |
Dfs &processedMap(ProcessedMap &m) |
390 | 389 |
{ |
391 | 390 |
if(local_processed) { |
392 | 391 |
delete _processed; |
393 | 392 |
local_processed=false; |
394 | 393 |
} |
395 | 394 |
_processed = &m; |
396 | 395 |
return *this; |
397 | 396 |
} |
398 | 397 |
|
399 | 398 |
///Sets the map that stores the distances of the nodes. |
400 | 399 |
|
401 | 400 |
///Sets the map that stores the distances of the nodes calculated by |
402 | 401 |
///the algorithm. |
403 | 402 |
///If you don't use this function before calling \ref run(), |
404 | 403 |
///it will allocate one. The destructor deallocates this |
405 | 404 |
///automatically allocated map, of course. |
406 | 405 |
///\return <tt> (*this) </tt> |
407 | 406 |
Dfs &distMap(DistMap &m) |
408 | 407 |
{ |
409 | 408 |
if(local_dist) { |
410 | 409 |
delete _dist; |
411 | 410 |
local_dist=false; |
412 | 411 |
} |
413 | 412 |
_dist = &m; |
414 | 413 |
return *this; |
415 | 414 |
} |
416 | 415 |
|
417 | 416 |
public: |
418 | 417 |
|
419 | 418 |
///\name Execution control |
420 | 419 |
///The simplest way to execute the algorithm is to use |
421 | 420 |
///one of the member functions called \ref lemon::Dfs::run() "run()". |
422 | 421 |
///\n |
423 | 422 |
///If you need more control on the execution, first you must call |
424 | 423 |
///\ref lemon::Dfs::init() "init()", then you can add a source node |
425 | 424 |
///with \ref lemon::Dfs::addSource() "addSource()". |
426 | 425 |
///Finally \ref lemon::Dfs::start() "start()" will perform the |
427 | 426 |
///actual path computation. |
428 | 427 |
|
429 | 428 |
///@{ |
430 | 429 |
|
431 | 430 |
///Initializes the internal data structures. |
432 | 431 |
|
433 | 432 |
///Initializes the internal data structures. |
434 | 433 |
/// |
435 | 434 |
void init() |
436 | 435 |
{ |
437 | 436 |
create_maps(); |
438 | 437 |
_stack.resize(countNodes(*G)); |
439 | 438 |
_stack_head=-1; |
440 | 439 |
for ( NodeIt u(*G) ; u!=INVALID ; ++u ) { |
441 | 440 |
_pred->set(u,INVALID); |
442 | 441 |
_reached->set(u,false); |
443 | 442 |
_processed->set(u,false); |
444 | 443 |
} |
445 | 444 |
} |
446 | 445 |
|
447 | 446 |
///Adds a new source node. |
448 | 447 |
|
449 | 448 |
///Adds a new source node to the set of nodes to be processed. |
450 | 449 |
/// |
451 | 450 |
///\pre The stack must be empty. (Otherwise the algorithm gives |
452 | 451 |
///false results.) |
453 | 452 |
/// |
454 | 453 |
///\warning Distances will be wrong (or at least strange) in case of |
455 | 454 |
///multiple sources. |
456 | 455 |
void addSource(Node s) |
457 | 456 |
{ |
458 | 457 |
LEMON_DEBUG(emptyQueue(), "The stack is not empty."); |
459 | 458 |
if(!(*_reached)[s]) |
460 | 459 |
{ |
461 | 460 |
_reached->set(s,true); |
462 | 461 |
_pred->set(s,INVALID); |
463 | 462 |
OutArcIt e(*G,s); |
464 | 463 |
if(e!=INVALID) { |
465 | 464 |
_stack[++_stack_head]=e; |
466 | 465 |
_dist->set(s,_stack_head); |
467 | 466 |
} |
468 | 467 |
else { |
469 | 468 |
_processed->set(s,true); |
470 | 469 |
_dist->set(s,0); |
471 | 470 |
} |
472 | 471 |
} |
473 | 472 |
} |
474 | 473 |
|
475 | 474 |
///Processes the next arc. |
476 | 475 |
|
477 | 476 |
///Processes the next arc. |
478 | 477 |
/// |
479 | 478 |
///\return The processed arc. |
480 | 479 |
/// |
481 | 480 |
///\pre The stack must not be empty. |
482 | 481 |
Arc processNextArc() |
483 | 482 |
{ |
484 | 483 |
Node m; |
485 | 484 |
Arc e=_stack[_stack_head]; |
486 | 485 |
if(!(*_reached)[m=G->target(e)]) { |
487 | 486 |
_pred->set(m,e); |
488 | 487 |
_reached->set(m,true); |
489 | 488 |
++_stack_head; |
490 | 489 |
_stack[_stack_head] = OutArcIt(*G, m); |
491 | 490 |
_dist->set(m,_stack_head); |
492 | 491 |
} |
493 | 492 |
else { |
494 | 493 |
m=G->source(e); |
495 | 494 |
++_stack[_stack_head]; |
496 | 495 |
} |
497 | 496 |
while(_stack_head>=0 && _stack[_stack_head]==INVALID) { |
498 | 497 |
_processed->set(m,true); |
499 | 498 |
--_stack_head; |
500 | 499 |
if(_stack_head>=0) { |
501 | 500 |
m=G->source(_stack[_stack_head]); |
502 | 501 |
++_stack[_stack_head]; |
503 | 502 |
} |
504 | 503 |
} |
505 | 504 |
return e; |
506 | 505 |
} |
507 | 506 |
|
508 | 507 |
///Next arc to be processed. |
509 | 508 |
|
510 | 509 |
///Next arc to be processed. |
511 | 510 |
/// |
512 | 511 |
///\return The next arc to be processed or \c INVALID if the stack |
513 | 512 |
///is empty. |
514 | 513 |
OutArcIt nextArc() const |
515 | 514 |
{ |
516 | 515 |
return _stack_head>=0?_stack[_stack_head]:INVALID; |
517 | 516 |
} |
518 | 517 |
|
519 | 518 |
///\brief Returns \c false if there are nodes |
520 | 519 |
///to be processed. |
521 | 520 |
/// |
522 | 521 |
///Returns \c false if there are nodes |
523 | 522 |
///to be processed in the queue (stack). |
524 | 523 |
bool emptyQueue() const { return _stack_head<0; } |
525 | 524 |
|
526 | 525 |
///Returns the number of the nodes to be processed. |
527 | 526 |
|
528 | 527 |
///Returns the number of the nodes to be processed in the queue (stack). |
529 | 528 |
int queueSize() const { return _stack_head+1; } |
530 | 529 |
|
531 | 530 |
///Executes the algorithm. |
532 | 531 |
|
533 | 532 |
///Executes the algorithm. |
534 | 533 |
/// |
535 | 534 |
///This method runs the %DFS algorithm from the root node |
536 | 535 |
///in order to compute the DFS path to each node. |
537 | 536 |
/// |
538 | 537 |
/// The algorithm computes |
539 | 538 |
///- the %DFS tree, |
540 | 539 |
///- the distance of each node from the root in the %DFS tree. |
541 | 540 |
/// |
542 | 541 |
///\pre init() must be called and a root node should be |
543 | 542 |
///added with addSource() before using this function. |
544 | 543 |
/// |
545 | 544 |
///\note <tt>d.start()</tt> is just a shortcut of the following code. |
546 | 545 |
///\code |
547 | 546 |
/// while ( !d.emptyQueue() ) { |
548 | 547 |
/// d.processNextArc(); |
549 | 548 |
/// } |
550 | 549 |
///\endcode |
551 | 550 |
void start() |
552 | 551 |
{ |
553 | 552 |
while ( !emptyQueue() ) processNextArc(); |
554 | 553 |
} |
555 | 554 |
|
556 | 555 |
///Executes the algorithm until the given target node is reached. |
557 | 556 |
|
558 | 557 |
///Executes the algorithm until the given target node is reached. |
559 | 558 |
/// |
560 | 559 |
///This method runs the %DFS algorithm from the root node |
561 | 560 |
///in order to compute the DFS path to \c dest. |
562 | 561 |
/// |
563 | 562 |
///The algorithm computes |
564 | 563 |
///- the %DFS path to \c dest, |
565 | 564 |
///- the distance of \c dest from the root in the %DFS tree. |
566 | 565 |
/// |
567 | 566 |
///\pre init() must be called and a root node should be |
568 | 567 |
///added with addSource() before using this function. |
569 | 568 |
void start(Node dest) |
570 | 569 |
{ |
571 | 570 |
while ( !emptyQueue() && G->target(_stack[_stack_head])!=dest ) |
572 | 571 |
processNextArc(); |
573 | 572 |
} |
574 | 573 |
|
575 | 574 |
///Executes the algorithm until a condition is met. |
576 | 575 |
|
... | ... |
@@ -747,827 +746,827 @@ |
747 | 746 |
///arcs, which form the DFS tree. |
748 | 747 |
/// |
749 | 748 |
///\pre Either \ref run() or \ref init() |
750 | 749 |
///must be called before using this function. |
751 | 750 |
const PredMap &predMap() const { return *_pred;} |
752 | 751 |
|
753 | 752 |
///Checks if a node is reachable from the root(s). |
754 | 753 |
|
755 | 754 |
///Returns \c true if \c v is reachable from the root(s). |
756 | 755 |
///\pre Either \ref run() or \ref start() |
757 | 756 |
///must be called before using this function. |
758 | 757 |
bool reached(Node v) const { return (*_reached)[v]; } |
759 | 758 |
|
760 | 759 |
///@} |
761 | 760 |
}; |
762 | 761 |
|
763 | 762 |
///Default traits class of dfs() function. |
764 | 763 |
|
765 | 764 |
///Default traits class of dfs() function. |
766 | 765 |
///\tparam GR Digraph type. |
767 | 766 |
template<class GR> |
768 | 767 |
struct DfsWizardDefaultTraits |
769 | 768 |
{ |
770 | 769 |
///The type of the digraph the algorithm runs on. |
771 | 770 |
typedef GR Digraph; |
772 | 771 |
|
773 | 772 |
///\brief The type of the map that stores the predecessor |
774 | 773 |
///arcs of the %DFS paths. |
775 | 774 |
/// |
776 | 775 |
///The type of the map that stores the predecessor |
777 | 776 |
///arcs of the %DFS paths. |
778 | 777 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
779 | 778 |
/// |
780 | 779 |
typedef NullMap<typename Digraph::Node,typename Digraph::Arc> PredMap; |
781 | 780 |
///Instantiates a \ref PredMap. |
782 | 781 |
|
783 | 782 |
///This function instantiates a \ref PredMap. |
784 | 783 |
///\param g is the digraph, to which we would like to define the |
785 | 784 |
///\ref PredMap. |
786 | 785 |
///\todo The digraph alone may be insufficient to initialize |
787 | 786 |
#ifdef DOXYGEN |
788 | 787 |
static PredMap *createPredMap(const Digraph &g) |
789 | 788 |
#else |
790 | 789 |
static PredMap *createPredMap(const Digraph &) |
791 | 790 |
#endif |
792 | 791 |
{ |
793 | 792 |
return new PredMap(); |
794 | 793 |
} |
795 | 794 |
|
796 | 795 |
///The type of the map that indicates which nodes are processed. |
797 | 796 |
|
798 | 797 |
///The type of the map that indicates which nodes are processed. |
799 | 798 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
800 | 799 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
801 | 800 |
///Instantiates a \ref ProcessedMap. |
802 | 801 |
|
803 | 802 |
///This function instantiates a \ref ProcessedMap. |
804 | 803 |
///\param g is the digraph, to which |
805 | 804 |
///we would like to define the \ref ProcessedMap. |
806 | 805 |
#ifdef DOXYGEN |
807 | 806 |
static ProcessedMap *createProcessedMap(const Digraph &g) |
808 | 807 |
#else |
809 | 808 |
static ProcessedMap *createProcessedMap(const Digraph &) |
810 | 809 |
#endif |
811 | 810 |
{ |
812 | 811 |
return new ProcessedMap(); |
813 | 812 |
} |
814 | 813 |
|
815 | 814 |
///The type of the map that indicates which nodes are reached. |
816 | 815 |
|
817 | 816 |
///The type of the map that indicates which nodes are reached. |
818 | 817 |
///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept. |
819 | 818 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
820 | 819 |
///Instantiates a \ref ReachedMap. |
821 | 820 |
|
822 | 821 |
///This function instantiates a \ref ReachedMap. |
823 | 822 |
///\param g is the digraph, to which |
824 | 823 |
///we would like to define the \ref ReachedMap. |
825 | 824 |
static ReachedMap *createReachedMap(const Digraph &g) |
826 | 825 |
{ |
827 | 826 |
return new ReachedMap(g); |
828 | 827 |
} |
829 | 828 |
|
830 | 829 |
///The type of the map that stores the distances of the nodes. |
831 | 830 |
|
832 | 831 |
///The type of the map that stores the distances of the nodes. |
833 | 832 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
834 | 833 |
/// |
835 | 834 |
typedef NullMap<typename Digraph::Node,int> DistMap; |
836 | 835 |
///Instantiates a \ref DistMap. |
837 | 836 |
|
838 | 837 |
///This function instantiates a \ref DistMap. |
839 | 838 |
///\param g is the digraph, to which we would like to define |
840 | 839 |
///the \ref DistMap |
841 | 840 |
#ifdef DOXYGEN |
842 | 841 |
static DistMap *createDistMap(const Digraph &g) |
843 | 842 |
#else |
844 | 843 |
static DistMap *createDistMap(const Digraph &) |
845 | 844 |
#endif |
846 | 845 |
{ |
847 | 846 |
return new DistMap(); |
848 | 847 |
} |
849 | 848 |
}; |
850 | 849 |
|
851 | 850 |
/// Default traits class used by \ref DfsWizard |
852 | 851 |
|
853 | 852 |
/// To make it easier to use Dfs algorithm |
854 | 853 |
/// we have created a wizard class. |
855 | 854 |
/// This \ref DfsWizard class needs default traits, |
856 | 855 |
/// as well as the \ref Dfs class. |
857 | 856 |
/// The \ref DfsWizardBase is a class to be the default traits of the |
858 | 857 |
/// \ref DfsWizard class. |
859 | 858 |
template<class GR> |
860 | 859 |
class DfsWizardBase : public DfsWizardDefaultTraits<GR> |
861 | 860 |
{ |
862 | 861 |
|
863 | 862 |
typedef DfsWizardDefaultTraits<GR> Base; |
864 | 863 |
protected: |
865 | 864 |
//The type of the nodes in the digraph. |
866 | 865 |
typedef typename Base::Digraph::Node Node; |
867 | 866 |
|
868 | 867 |
//Pointer to the digraph the algorithm runs on. |
869 | 868 |
void *_g; |
870 | 869 |
//Pointer to the map of reached nodes. |
871 | 870 |
void *_reached; |
872 | 871 |
//Pointer to the map of processed nodes. |
873 | 872 |
void *_processed; |
874 | 873 |
//Pointer to the map of predecessors arcs. |
875 | 874 |
void *_pred; |
876 | 875 |
//Pointer to the map of distances. |
877 | 876 |
void *_dist; |
878 | 877 |
//Pointer to the source node. |
879 | 878 |
Node _source; |
880 | 879 |
|
881 | 880 |
public: |
882 | 881 |
/// Constructor. |
883 | 882 |
|
884 | 883 |
/// This constructor does not require parameters, therefore it initiates |
885 | 884 |
/// all of the attributes to default values (0, INVALID). |
886 | 885 |
DfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0), |
887 | 886 |
_dist(0), _source(INVALID) {} |
888 | 887 |
|
889 | 888 |
/// Constructor. |
890 | 889 |
|
891 | 890 |
/// This constructor requires some parameters, |
892 | 891 |
/// listed in the parameters list. |
893 | 892 |
/// Others are initiated to 0. |
894 | 893 |
/// \param g The digraph the algorithm runs on. |
895 | 894 |
/// \param s The source node. |
896 | 895 |
DfsWizardBase(const GR &g, Node s=INVALID) : |
897 | 896 |
_g(reinterpret_cast<void*>(const_cast<GR*>(&g))), |
898 | 897 |
_reached(0), _processed(0), _pred(0), _dist(0), _source(s) {} |
899 | 898 |
|
900 | 899 |
}; |
901 | 900 |
|
902 | 901 |
/// Auxiliary class for the function type interface of DFS algorithm. |
903 | 902 |
|
904 | 903 |
/// This auxiliary class is created to implement the function type |
905 | 904 |
/// interface of \ref Dfs algorithm. It uses the functions and features |
906 | 905 |
/// of the plain \ref Dfs, but it is much simpler to use it. |
907 | 906 |
/// It should only be used through the \ref dfs() function, which makes |
908 | 907 |
/// it easier to use the algorithm. |
909 | 908 |
/// |
910 | 909 |
/// Simplicity means that the way to change the types defined |
911 | 910 |
/// in the traits class is based on functions that returns the new class |
912 | 911 |
/// and not on templatable built-in classes. |
913 | 912 |
/// When using the plain \ref Dfs |
914 | 913 |
/// the new class with the modified type comes from |
915 | 914 |
/// the original class by using the :: |
916 | 915 |
/// operator. In the case of \ref DfsWizard only |
917 | 916 |
/// a function have to be called, and it will |
918 | 917 |
/// return the needed class. |
919 | 918 |
/// |
920 | 919 |
/// It does not have own \ref run() method. When its \ref run() method |
921 | 920 |
/// is called, it initiates a plain \ref Dfs object, and calls the |
922 | 921 |
/// \ref Dfs::run() method of it. |
923 | 922 |
template<class TR> |
924 | 923 |
class DfsWizard : public TR |
925 | 924 |
{ |
926 | 925 |
typedef TR Base; |
927 | 926 |
|
928 | 927 |
///The type of the digraph the algorithm runs on. |
929 | 928 |
typedef typename TR::Digraph Digraph; |
930 | 929 |
|
931 | 930 |
typedef typename Digraph::Node Node; |
932 | 931 |
typedef typename Digraph::NodeIt NodeIt; |
933 | 932 |
typedef typename Digraph::Arc Arc; |
934 | 933 |
typedef typename Digraph::OutArcIt OutArcIt; |
935 | 934 |
|
936 | 935 |
///\brief The type of the map that stores the predecessor |
937 | 936 |
///arcs of the shortest paths. |
938 | 937 |
typedef typename TR::PredMap PredMap; |
939 | 938 |
///\brief The type of the map that stores the distances of the nodes. |
940 | 939 |
typedef typename TR::DistMap DistMap; |
941 | 940 |
///\brief The type of the map that indicates which nodes are reached. |
942 | 941 |
typedef typename TR::ReachedMap ReachedMap; |
943 | 942 |
///\brief The type of the map that indicates which nodes are processed. |
944 | 943 |
typedef typename TR::ProcessedMap ProcessedMap; |
945 | 944 |
|
946 | 945 |
public: |
947 | 946 |
|
948 | 947 |
/// Constructor. |
949 | 948 |
DfsWizard() : TR() {} |
950 | 949 |
|
951 | 950 |
/// Constructor that requires parameters. |
952 | 951 |
|
953 | 952 |
/// Constructor that requires parameters. |
954 | 953 |
/// These parameters will be the default values for the traits class. |
955 | 954 |
DfsWizard(const Digraph &g, Node s=INVALID) : |
956 | 955 |
TR(g,s) {} |
957 | 956 |
|
958 | 957 |
///Copy constructor |
959 | 958 |
DfsWizard(const TR &b) : TR(b) {} |
960 | 959 |
|
961 | 960 |
~DfsWizard() {} |
962 | 961 |
|
963 | 962 |
///Runs DFS algorithm from a source node. |
964 | 963 |
|
965 | 964 |
///Runs DFS algorithm from a source node. |
966 | 965 |
///The node can be given with the \ref source() function. |
967 | 966 |
void run() |
968 | 967 |
{ |
969 | 968 |
if(Base::_source==INVALID) throw UninitializedParameter(); |
970 | 969 |
Dfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g)); |
971 | 970 |
if(Base::_reached) |
972 | 971 |
alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached)); |
973 | 972 |
if(Base::_processed) |
974 | 973 |
alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed)); |
975 | 974 |
if(Base::_pred) |
976 | 975 |
alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred)); |
977 | 976 |
if(Base::_dist) |
978 | 977 |
alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist)); |
979 | 978 |
alg.run(Base::_source); |
980 | 979 |
} |
981 | 980 |
|
982 | 981 |
///Runs DFS algorithm from the given node. |
983 | 982 |
|
984 | 983 |
///Runs DFS algorithm from the given node. |
985 | 984 |
///\param s is the given source. |
986 | 985 |
void run(Node s) |
987 | 986 |
{ |
988 | 987 |
Base::_source=s; |
989 | 988 |
run(); |
990 | 989 |
} |
991 | 990 |
|
992 | 991 |
/// Sets the source node, from which the Dfs algorithm runs. |
993 | 992 |
|
994 | 993 |
/// Sets the source node, from which the Dfs algorithm runs. |
995 | 994 |
/// \param s is the source node. |
996 | 995 |
DfsWizard<TR> &source(Node s) |
997 | 996 |
{ |
998 | 997 |
Base::_source=s; |
999 | 998 |
return *this; |
1000 | 999 |
} |
1001 | 1000 |
|
1002 | 1001 |
template<class T> |
1003 |
struct |
|
1002 |
struct SetPredMapBase : public Base { |
|
1004 | 1003 |
typedef T PredMap; |
1005 | 1004 |
static PredMap *createPredMap(const Digraph &) { return 0; }; |
1006 |
|
|
1005 |
SetPredMapBase(const TR &b) : TR(b) {} |
|
1007 | 1006 |
}; |
1008 | 1007 |
///\brief \ref named-templ-param "Named parameter" |
1009 | 1008 |
///for setting \ref PredMap object. |
1010 | 1009 |
/// |
1011 | 1010 |
///\ref named-templ-param "Named parameter" |
1012 | 1011 |
///for setting \ref PredMap object. |
1013 | 1012 |
template<class T> |
1014 |
DfsWizard< |
|
1013 |
DfsWizard<SetPredMapBase<T> > predMap(const T &t) |
|
1015 | 1014 |
{ |
1016 | 1015 |
Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1017 |
return DfsWizard< |
|
1016 |
return DfsWizard<SetPredMapBase<T> >(*this); |
|
1018 | 1017 |
} |
1019 | 1018 |
|
1020 | 1019 |
template<class T> |
1021 |
struct |
|
1020 |
struct SetReachedMapBase : public Base { |
|
1022 | 1021 |
typedef T ReachedMap; |
1023 | 1022 |
static ReachedMap *createReachedMap(const Digraph &) { return 0; }; |
1024 |
|
|
1023 |
SetReachedMapBase(const TR &b) : TR(b) {} |
|
1025 | 1024 |
}; |
1026 | 1025 |
///\brief \ref named-templ-param "Named parameter" |
1027 | 1026 |
///for setting \ref ReachedMap object. |
1028 | 1027 |
/// |
1029 | 1028 |
/// \ref named-templ-param "Named parameter" |
1030 | 1029 |
///for setting \ref ReachedMap object. |
1031 | 1030 |
template<class T> |
1032 |
DfsWizard< |
|
1031 |
DfsWizard<SetReachedMapBase<T> > reachedMap(const T &t) |
|
1033 | 1032 |
{ |
1034 | 1033 |
Base::_reached=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1035 |
return DfsWizard< |
|
1034 |
return DfsWizard<SetReachedMapBase<T> >(*this); |
|
1036 | 1035 |
} |
1037 | 1036 |
|
1038 | 1037 |
template<class T> |
1039 |
struct |
|
1038 |
struct SetProcessedMapBase : public Base { |
|
1040 | 1039 |
typedef T ProcessedMap; |
1041 | 1040 |
static ProcessedMap *createProcessedMap(const Digraph &) { return 0; }; |
1042 |
|
|
1041 |
SetProcessedMapBase(const TR &b) : TR(b) {} |
|
1043 | 1042 |
}; |
1044 | 1043 |
///\brief \ref named-templ-param "Named parameter" |
1045 | 1044 |
///for setting \ref ProcessedMap object. |
1046 | 1045 |
/// |
1047 | 1046 |
/// \ref named-templ-param "Named parameter" |
1048 | 1047 |
///for setting \ref ProcessedMap object. |
1049 | 1048 |
template<class T> |
1050 |
DfsWizard< |
|
1049 |
DfsWizard<SetProcessedMapBase<T> > processedMap(const T &t) |
|
1051 | 1050 |
{ |
1052 | 1051 |
Base::_processed=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1053 |
return DfsWizard< |
|
1052 |
return DfsWizard<SetProcessedMapBase<T> >(*this); |
|
1054 | 1053 |
} |
1055 | 1054 |
|
1056 | 1055 |
template<class T> |
1057 |
struct |
|
1056 |
struct SetDistMapBase : public Base { |
|
1058 | 1057 |
typedef T DistMap; |
1059 | 1058 |
static DistMap *createDistMap(const Digraph &) { return 0; }; |
1060 |
|
|
1059 |
SetDistMapBase(const TR &b) : TR(b) {} |
|
1061 | 1060 |
}; |
1062 | 1061 |
///\brief \ref named-templ-param "Named parameter" |
1063 | 1062 |
///for setting \ref DistMap object. |
1064 | 1063 |
/// |
1065 | 1064 |
///\ref named-templ-param "Named parameter" |
1066 | 1065 |
///for setting \ref DistMap object. |
1067 | 1066 |
template<class T> |
1068 |
DfsWizard< |
|
1067 |
DfsWizard<SetDistMapBase<T> > distMap(const T &t) |
|
1069 | 1068 |
{ |
1070 | 1069 |
Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1071 |
return DfsWizard< |
|
1070 |
return DfsWizard<SetDistMapBase<T> >(*this); |
|
1072 | 1071 |
} |
1073 | 1072 |
|
1074 | 1073 |
}; |
1075 | 1074 |
|
1076 | 1075 |
///Function type interface for Dfs algorithm. |
1077 | 1076 |
|
1078 | 1077 |
///\ingroup search |
1079 | 1078 |
///Function type interface for Dfs algorithm. |
1080 | 1079 |
/// |
1081 | 1080 |
///This function also has several |
1082 | 1081 |
///\ref named-templ-func-param "named parameters", |
1083 | 1082 |
///they are declared as the members of class \ref DfsWizard. |
1084 | 1083 |
///The following |
1085 | 1084 |
///example shows how to use these parameters. |
1086 | 1085 |
///\code |
1087 | 1086 |
/// dfs(g,source).predMap(preds).run(); |
1088 | 1087 |
///\endcode |
1089 | 1088 |
///\warning Don't forget to put the \ref DfsWizard::run() "run()" |
1090 | 1089 |
///to the end of the parameter list. |
1091 | 1090 |
///\sa DfsWizard |
1092 | 1091 |
///\sa Dfs |
1093 | 1092 |
template<class GR> |
1094 | 1093 |
DfsWizard<DfsWizardBase<GR> > |
1095 | 1094 |
dfs(const GR &g,typename GR::Node s=INVALID) |
1096 | 1095 |
{ |
1097 | 1096 |
return DfsWizard<DfsWizardBase<GR> >(g,s); |
1098 | 1097 |
} |
1099 | 1098 |
|
1100 | 1099 |
#ifdef DOXYGEN |
1101 | 1100 |
/// \brief Visitor class for DFS. |
1102 | 1101 |
/// |
1103 | 1102 |
/// This class defines the interface of the DfsVisit events, and |
1104 | 1103 |
/// it could be the base of a real visitor class. |
1105 | 1104 |
template <typename _Digraph> |
1106 | 1105 |
struct DfsVisitor { |
1107 | 1106 |
typedef _Digraph Digraph; |
1108 | 1107 |
typedef typename Digraph::Arc Arc; |
1109 | 1108 |
typedef typename Digraph::Node Node; |
1110 | 1109 |
/// \brief Called for the source node of the DFS. |
1111 | 1110 |
/// |
1112 | 1111 |
/// This function is called for the source node of the DFS. |
1113 | 1112 |
void start(const Node& node) {} |
1114 | 1113 |
/// \brief Called when the source node is leaved. |
1115 | 1114 |
/// |
1116 | 1115 |
/// This function is called when the source node is leaved. |
1117 | 1116 |
void stop(const Node& node) {} |
1118 | 1117 |
/// \brief Called when a node is reached first time. |
1119 | 1118 |
/// |
1120 | 1119 |
/// This function is called when a node is reached first time. |
1121 | 1120 |
void reach(const Node& node) {} |
1122 | 1121 |
/// \brief Called when an arc reaches a new node. |
1123 | 1122 |
/// |
1124 | 1123 |
/// This function is called when the DFS finds an arc whose target node |
1125 | 1124 |
/// is not reached yet. |
1126 | 1125 |
void discover(const Arc& arc) {} |
1127 | 1126 |
/// \brief Called when an arc is examined but its target node is |
1128 | 1127 |
/// already discovered. |
1129 | 1128 |
/// |
1130 | 1129 |
/// This function is called when an arc is examined but its target node is |
1131 | 1130 |
/// already discovered. |
1132 | 1131 |
void examine(const Arc& arc) {} |
1133 | 1132 |
/// \brief Called when the DFS steps back from a node. |
1134 | 1133 |
/// |
1135 | 1134 |
/// This function is called when the DFS steps back from a node. |
1136 | 1135 |
void leave(const Node& node) {} |
1137 | 1136 |
/// \brief Called when the DFS steps back on an arc. |
1138 | 1137 |
/// |
1139 | 1138 |
/// This function is called when the DFS steps back on an arc. |
1140 | 1139 |
void backtrack(const Arc& arc) {} |
1141 | 1140 |
}; |
1142 | 1141 |
#else |
1143 | 1142 |
template <typename _Digraph> |
1144 | 1143 |
struct DfsVisitor { |
1145 | 1144 |
typedef _Digraph Digraph; |
1146 | 1145 |
typedef typename Digraph::Arc Arc; |
1147 | 1146 |
typedef typename Digraph::Node Node; |
1148 | 1147 |
void start(const Node&) {} |
1149 | 1148 |
void stop(const Node&) {} |
1150 | 1149 |
void reach(const Node&) {} |
1151 | 1150 |
void discover(const Arc&) {} |
1152 | 1151 |
void examine(const Arc&) {} |
1153 | 1152 |
void leave(const Node&) {} |
1154 | 1153 |
void backtrack(const Arc&) {} |
1155 | 1154 |
|
1156 | 1155 |
template <typename _Visitor> |
1157 | 1156 |
struct Constraints { |
1158 | 1157 |
void constraints() { |
1159 | 1158 |
Arc arc; |
1160 | 1159 |
Node node; |
1161 | 1160 |
visitor.start(node); |
1162 | 1161 |
visitor.stop(arc); |
1163 | 1162 |
visitor.reach(node); |
1164 | 1163 |
visitor.discover(arc); |
1165 | 1164 |
visitor.examine(arc); |
1166 | 1165 |
visitor.leave(node); |
1167 | 1166 |
visitor.backtrack(arc); |
1168 | 1167 |
} |
1169 | 1168 |
_Visitor& visitor; |
1170 | 1169 |
}; |
1171 | 1170 |
}; |
1172 | 1171 |
#endif |
1173 | 1172 |
|
1174 | 1173 |
/// \brief Default traits class of DfsVisit class. |
1175 | 1174 |
/// |
1176 | 1175 |
/// Default traits class of DfsVisit class. |
1177 | 1176 |
/// \tparam _Digraph The type of the digraph the algorithm runs on. |
1178 | 1177 |
template<class _Digraph> |
1179 | 1178 |
struct DfsVisitDefaultTraits { |
1180 | 1179 |
|
1181 | 1180 |
/// \brief The type of the digraph the algorithm runs on. |
1182 | 1181 |
typedef _Digraph Digraph; |
1183 | 1182 |
|
1184 | 1183 |
/// \brief The type of the map that indicates which nodes are reached. |
1185 | 1184 |
/// |
1186 | 1185 |
/// The type of the map that indicates which nodes are reached. |
1187 | 1186 |
/// It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept. |
1188 | 1187 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
1189 | 1188 |
|
1190 | 1189 |
/// \brief Instantiates a \ref ReachedMap. |
1191 | 1190 |
/// |
1192 | 1191 |
/// This function instantiates a \ref ReachedMap. |
1193 | 1192 |
/// \param digraph is the digraph, to which |
1194 | 1193 |
/// we would like to define the \ref ReachedMap. |
1195 | 1194 |
static ReachedMap *createReachedMap(const Digraph &digraph) { |
1196 | 1195 |
return new ReachedMap(digraph); |
1197 | 1196 |
} |
1198 | 1197 |
|
1199 | 1198 |
}; |
1200 | 1199 |
|
1201 | 1200 |
/// \ingroup search |
1202 | 1201 |
/// |
1203 | 1202 |
/// \brief %DFS algorithm class with visitor interface. |
1204 | 1203 |
/// |
1205 | 1204 |
/// This class provides an efficient implementation of the %DFS algorithm |
1206 | 1205 |
/// with visitor interface. |
1207 | 1206 |
/// |
1208 | 1207 |
/// The %DfsVisit class provides an alternative interface to the Dfs |
1209 | 1208 |
/// class. It works with callback mechanism, the DfsVisit object calls |
1210 | 1209 |
/// the member functions of the \c Visitor class on every DFS event. |
1211 | 1210 |
/// |
1212 | 1211 |
/// This interface of the DFS algorithm should be used in special cases |
1213 | 1212 |
/// when extra actions have to be performed in connection with certain |
1214 | 1213 |
/// events of the DFS algorithm. Otherwise consider to use Dfs or dfs() |
1215 | 1214 |
/// instead. |
1216 | 1215 |
/// |
1217 | 1216 |
/// \tparam _Digraph The type of the digraph the algorithm runs on. |
1218 | 1217 |
/// The default value is |
1219 | 1218 |
/// \ref ListDigraph. The value of _Digraph is not used directly by |
1220 | 1219 |
/// \ref DfsVisit, it is only passed to \ref DfsVisitDefaultTraits. |
1221 | 1220 |
/// \tparam _Visitor The Visitor type that is used by the algorithm. |
1222 | 1221 |
/// \ref DfsVisitor "DfsVisitor<_Digraph>" is an empty visitor, which |
1223 | 1222 |
/// does not observe the DFS events. If you want to observe the DFS |
1224 | 1223 |
/// events, you should implement your own visitor class. |
1225 | 1224 |
/// \tparam _Traits Traits class to set various data types used by the |
1226 | 1225 |
/// algorithm. The default traits class is |
1227 | 1226 |
/// \ref DfsVisitDefaultTraits "DfsVisitDefaultTraits<_Digraph>". |
1228 | 1227 |
/// See \ref DfsVisitDefaultTraits for the documentation of |
1229 | 1228 |
/// a DFS visit traits class. |
1230 | 1229 |
#ifdef DOXYGEN |
1231 | 1230 |
template <typename _Digraph, typename _Visitor, typename _Traits> |
1232 | 1231 |
#else |
1233 | 1232 |
template <typename _Digraph = ListDigraph, |
1234 | 1233 |
typename _Visitor = DfsVisitor<_Digraph>, |
1235 | 1234 |
typename _Traits = DfsDefaultTraits<_Digraph> > |
1236 | 1235 |
#endif |
1237 | 1236 |
class DfsVisit { |
1238 | 1237 |
public: |
1239 | 1238 |
|
1240 | 1239 |
/// \brief \ref Exception for uninitialized parameters. |
1241 | 1240 |
/// |
1242 | 1241 |
/// This error represents problems in the initialization |
1243 | 1242 |
/// of the parameters of the algorithm. |
1244 | 1243 |
class UninitializedParameter : public lemon::UninitializedParameter { |
1245 | 1244 |
public: |
1246 | 1245 |
virtual const char* what() const throw() |
1247 | 1246 |
{ |
1248 | 1247 |
return "lemon::DfsVisit::UninitializedParameter"; |
1249 | 1248 |
} |
1250 | 1249 |
}; |
1251 | 1250 |
|
1252 | 1251 |
///The traits class. |
1253 | 1252 |
typedef _Traits Traits; |
1254 | 1253 |
|
1255 | 1254 |
///The type of the digraph the algorithm runs on. |
1256 | 1255 |
typedef typename Traits::Digraph Digraph; |
1257 | 1256 |
|
1258 | 1257 |
///The visitor type used by the algorithm. |
1259 | 1258 |
typedef _Visitor Visitor; |
1260 | 1259 |
|
1261 | 1260 |
///The type of the map that indicates which nodes are reached. |
1262 | 1261 |
typedef typename Traits::ReachedMap ReachedMap; |
1263 | 1262 |
|
1264 | 1263 |
private: |
1265 | 1264 |
|
1266 | 1265 |
typedef typename Digraph::Node Node; |
1267 | 1266 |
typedef typename Digraph::NodeIt NodeIt; |
1268 | 1267 |
typedef typename Digraph::Arc Arc; |
1269 | 1268 |
typedef typename Digraph::OutArcIt OutArcIt; |
1270 | 1269 |
|
1271 | 1270 |
//Pointer to the underlying digraph. |
1272 | 1271 |
const Digraph *_digraph; |
1273 | 1272 |
//Pointer to the visitor object. |
1274 | 1273 |
Visitor *_visitor; |
1275 | 1274 |
//Pointer to the map of reached status of the nodes. |
1276 | 1275 |
ReachedMap *_reached; |
1277 | 1276 |
//Indicates if _reached is locally allocated (true) or not. |
1278 | 1277 |
bool local_reached; |
1279 | 1278 |
|
1280 | 1279 |
std::vector<typename Digraph::Arc> _stack; |
1281 | 1280 |
int _stack_head; |
1282 | 1281 |
|
1283 | 1282 |
///Creates the maps if necessary. |
1284 | 1283 |
///\todo Better memory allocation (instead of new). |
1285 | 1284 |
void create_maps() { |
1286 | 1285 |
if(!_reached) { |
1287 | 1286 |
local_reached = true; |
1288 | 1287 |
_reached = Traits::createReachedMap(*_digraph); |
1289 | 1288 |
} |
1290 | 1289 |
} |
1291 | 1290 |
|
1292 | 1291 |
protected: |
1293 | 1292 |
|
1294 | 1293 |
DfsVisit() {} |
1295 | 1294 |
|
1296 | 1295 |
public: |
1297 | 1296 |
|
1298 | 1297 |
typedef DfsVisit Create; |
1299 | 1298 |
|
1300 | 1299 |
/// \name Named template parameters |
1301 | 1300 |
|
1302 | 1301 |
///@{ |
1303 | 1302 |
template <class T> |
1304 |
struct |
|
1303 |
struct SetReachedMapTraits : public Traits { |
|
1305 | 1304 |
typedef T ReachedMap; |
1306 | 1305 |
static ReachedMap *createReachedMap(const Digraph &digraph) { |
1307 | 1306 |
throw UninitializedParameter(); |
1308 | 1307 |
} |
1309 | 1308 |
}; |
1310 | 1309 |
/// \brief \ref named-templ-param "Named parameter" for setting |
1311 | 1310 |
/// ReachedMap type. |
1312 | 1311 |
/// |
1313 | 1312 |
/// \ref named-templ-param "Named parameter" for setting ReachedMap type. |
1314 | 1313 |
template <class T> |
1315 |
struct DefReachedMap : public DfsVisit< Digraph, Visitor, |
|
1316 |
DefReachedMapTraits<T> > { |
|
1317 |
|
|
1314 |
struct SetReachedMap : public DfsVisit< Digraph, Visitor, |
|
1315 |
SetReachedMapTraits<T> > { |
|
1316 |
typedef DfsVisit< Digraph, Visitor, SetReachedMapTraits<T> > Create; |
|
1318 | 1317 |
}; |
1319 | 1318 |
///@} |
1320 | 1319 |
|
1321 | 1320 |
public: |
1322 | 1321 |
|
1323 | 1322 |
/// \brief Constructor. |
1324 | 1323 |
/// |
1325 | 1324 |
/// Constructor. |
1326 | 1325 |
/// |
1327 | 1326 |
/// \param digraph The digraph the algorithm runs on. |
1328 | 1327 |
/// \param visitor The visitor object of the algorithm. |
1329 | 1328 |
DfsVisit(const Digraph& digraph, Visitor& visitor) |
1330 | 1329 |
: _digraph(&digraph), _visitor(&visitor), |
1331 | 1330 |
_reached(0), local_reached(false) {} |
1332 | 1331 |
|
1333 | 1332 |
/// \brief Destructor. |
1334 | 1333 |
~DfsVisit() { |
1335 | 1334 |
if(local_reached) delete _reached; |
1336 | 1335 |
} |
1337 | 1336 |
|
1338 | 1337 |
/// \brief Sets the map that indicates which nodes are reached. |
1339 | 1338 |
/// |
1340 | 1339 |
/// Sets the map that indicates which nodes are reached. |
1341 | 1340 |
/// If you don't use this function before calling \ref run(), |
1342 | 1341 |
/// it will allocate one. The destructor deallocates this |
1343 | 1342 |
/// automatically allocated map, of course. |
1344 | 1343 |
/// \return <tt> (*this) </tt> |
1345 | 1344 |
DfsVisit &reachedMap(ReachedMap &m) { |
1346 | 1345 |
if(local_reached) { |
1347 | 1346 |
delete _reached; |
1348 | 1347 |
local_reached=false; |
1349 | 1348 |
} |
1350 | 1349 |
_reached = &m; |
1351 | 1350 |
return *this; |
1352 | 1351 |
} |
1353 | 1352 |
|
1354 | 1353 |
public: |
1355 | 1354 |
|
1356 | 1355 |
/// \name Execution control |
1357 | 1356 |
/// The simplest way to execute the algorithm is to use |
1358 | 1357 |
/// one of the member functions called \ref lemon::DfsVisit::run() |
1359 | 1358 |
/// "run()". |
1360 | 1359 |
/// \n |
1361 | 1360 |
/// If you need more control on the execution, first you must call |
1362 | 1361 |
/// \ref lemon::DfsVisit::init() "init()", then you can add several |
1363 | 1362 |
/// source nodes with \ref lemon::DfsVisit::addSource() "addSource()". |
1364 | 1363 |
/// Finally \ref lemon::DfsVisit::start() "start()" will perform the |
1365 | 1364 |
/// actual path computation. |
1366 | 1365 |
|
1367 | 1366 |
/// @{ |
1368 | 1367 |
|
1369 | 1368 |
/// \brief Initializes the internal data structures. |
1370 | 1369 |
/// |
1371 | 1370 |
/// Initializes the internal data structures. |
1372 | 1371 |
void init() { |
1373 | 1372 |
create_maps(); |
1374 | 1373 |
_stack.resize(countNodes(*_digraph)); |
1375 | 1374 |
_stack_head = -1; |
1376 | 1375 |
for (NodeIt u(*_digraph) ; u != INVALID ; ++u) { |
1377 | 1376 |
_reached->set(u, false); |
1378 | 1377 |
} |
1379 | 1378 |
} |
1380 | 1379 |
|
1381 | 1380 |
///Adds a new source node. |
1382 | 1381 |
|
1383 | 1382 |
///Adds a new source node to the set of nodes to be processed. |
1384 | 1383 |
/// |
1385 | 1384 |
///\pre The stack must be empty. (Otherwise the algorithm gives |
1386 | 1385 |
///false results.) |
1387 | 1386 |
/// |
1388 | 1387 |
///\warning Distances will be wrong (or at least strange) in case of |
1389 | 1388 |
///multiple sources. |
1390 | 1389 |
void addSource(Node s) |
1391 | 1390 |
{ |
1392 | 1391 |
LEMON_DEBUG(emptyQueue(), "The stack is not empty."); |
1393 | 1392 |
if(!(*_reached)[s]) { |
1394 | 1393 |
_reached->set(s,true); |
1395 | 1394 |
_visitor->start(s); |
1396 | 1395 |
_visitor->reach(s); |
1397 | 1396 |
Arc e; |
1398 | 1397 |
_digraph->firstOut(e, s); |
1399 | 1398 |
if (e != INVALID) { |
1400 | 1399 |
_stack[++_stack_head] = e; |
1401 | 1400 |
} else { |
1402 | 1401 |
_visitor->leave(s); |
1403 | 1402 |
} |
1404 | 1403 |
} |
1405 | 1404 |
} |
1406 | 1405 |
|
1407 | 1406 |
/// \brief Processes the next arc. |
1408 | 1407 |
/// |
1409 | 1408 |
/// Processes the next arc. |
1410 | 1409 |
/// |
1411 | 1410 |
/// \return The processed arc. |
1412 | 1411 |
/// |
1413 | 1412 |
/// \pre The stack must not be empty. |
1414 | 1413 |
Arc processNextArc() { |
1415 | 1414 |
Arc e = _stack[_stack_head]; |
1416 | 1415 |
Node m = _digraph->target(e); |
1417 | 1416 |
if(!(*_reached)[m]) { |
1418 | 1417 |
_visitor->discover(e); |
1419 | 1418 |
_visitor->reach(m); |
1420 | 1419 |
_reached->set(m, true); |
1421 | 1420 |
_digraph->firstOut(_stack[++_stack_head], m); |
1422 | 1421 |
} else { |
1423 | 1422 |
_visitor->examine(e); |
1424 | 1423 |
m = _digraph->source(e); |
1425 | 1424 |
_digraph->nextOut(_stack[_stack_head]); |
1426 | 1425 |
} |
1427 | 1426 |
while (_stack_head>=0 && _stack[_stack_head] == INVALID) { |
1428 | 1427 |
_visitor->leave(m); |
1429 | 1428 |
--_stack_head; |
1430 | 1429 |
if (_stack_head >= 0) { |
1431 | 1430 |
_visitor->backtrack(_stack[_stack_head]); |
1432 | 1431 |
m = _digraph->source(_stack[_stack_head]); |
1433 | 1432 |
_digraph->nextOut(_stack[_stack_head]); |
1434 | 1433 |
} else { |
1435 | 1434 |
_visitor->stop(m); |
1436 | 1435 |
} |
1437 | 1436 |
} |
1438 | 1437 |
return e; |
1439 | 1438 |
} |
1440 | 1439 |
|
1441 | 1440 |
/// \brief Next arc to be processed. |
1442 | 1441 |
/// |
1443 | 1442 |
/// Next arc to be processed. |
1444 | 1443 |
/// |
1445 | 1444 |
/// \return The next arc to be processed or INVALID if the stack is |
1446 | 1445 |
/// empty. |
1447 | 1446 |
Arc nextArc() const { |
1448 | 1447 |
return _stack_head >= 0 ? _stack[_stack_head] : INVALID; |
1449 | 1448 |
} |
1450 | 1449 |
|
1451 | 1450 |
/// \brief Returns \c false if there are nodes |
1452 | 1451 |
/// to be processed. |
1453 | 1452 |
/// |
1454 | 1453 |
/// Returns \c false if there are nodes |
1455 | 1454 |
/// to be processed in the queue (stack). |
1456 | 1455 |
bool emptyQueue() const { return _stack_head < 0; } |
1457 | 1456 |
|
1458 | 1457 |
/// \brief Returns the number of the nodes to be processed. |
1459 | 1458 |
/// |
1460 | 1459 |
/// Returns the number of the nodes to be processed in the queue (stack). |
1461 | 1460 |
int queueSize() const { return _stack_head + 1; } |
1462 | 1461 |
|
1463 | 1462 |
/// \brief Executes the algorithm. |
1464 | 1463 |
/// |
1465 | 1464 |
/// Executes the algorithm. |
1466 | 1465 |
/// |
1467 | 1466 |
/// This method runs the %DFS algorithm from the root node |
1468 | 1467 |
/// in order to compute the %DFS path to each node. |
1469 | 1468 |
/// |
1470 | 1469 |
/// The algorithm computes |
1471 | 1470 |
/// - the %DFS tree, |
1472 | 1471 |
/// - the distance of each node from the root in the %DFS tree. |
1473 | 1472 |
/// |
1474 | 1473 |
/// \pre init() must be called and a root node should be |
1475 | 1474 |
/// added with addSource() before using this function. |
1476 | 1475 |
/// |
1477 | 1476 |
/// \note <tt>d.start()</tt> is just a shortcut of the following code. |
1478 | 1477 |
/// \code |
1479 | 1478 |
/// while ( !d.emptyQueue() ) { |
1480 | 1479 |
/// d.processNextArc(); |
1481 | 1480 |
/// } |
1482 | 1481 |
/// \endcode |
1483 | 1482 |
void start() { |
1484 | 1483 |
while ( !emptyQueue() ) processNextArc(); |
1485 | 1484 |
} |
1486 | 1485 |
|
1487 | 1486 |
/// \brief Executes the algorithm until the given target node is reached. |
1488 | 1487 |
/// |
1489 | 1488 |
/// Executes the algorithm until the given target node is reached. |
1490 | 1489 |
/// |
1491 | 1490 |
/// This method runs the %DFS algorithm from the root node |
1492 | 1491 |
/// in order to compute the DFS path to \c dest. |
1493 | 1492 |
/// |
1494 | 1493 |
/// The algorithm computes |
1495 | 1494 |
/// - the %DFS path to \c dest, |
1496 | 1495 |
/// - the distance of \c dest from the root in the %DFS tree. |
1497 | 1496 |
/// |
1498 | 1497 |
/// \pre init() must be called and a root node should be added |
1499 | 1498 |
/// with addSource() before using this function. |
1500 | 1499 |
void start(Node dest) { |
1501 | 1500 |
while ( !emptyQueue() && _digraph->target(_stack[_stack_head]) != dest ) |
1502 | 1501 |
processNextArc(); |
1503 | 1502 |
} |
1504 | 1503 |
|
1505 | 1504 |
/// \brief Executes the algorithm until a condition is met. |
1506 | 1505 |
/// |
1507 | 1506 |
/// Executes the algorithm until a condition is met. |
1508 | 1507 |
/// |
1509 | 1508 |
/// This method runs the %DFS algorithm from the root node |
1510 | 1509 |
/// until an arc \c a with <tt>am[a]</tt> true is found. |
1511 | 1510 |
/// |
1512 | 1511 |
/// \param am A \c bool (or convertible) arc map. The algorithm |
1513 | 1512 |
/// will stop when it reaches an arc \c a with <tt>am[a]</tt> true. |
1514 | 1513 |
/// |
1515 | 1514 |
/// \return The reached arc \c a with <tt>am[a]</tt> true or |
1516 | 1515 |
/// \c INVALID if no such arc was found. |
1517 | 1516 |
/// |
1518 | 1517 |
/// \pre init() must be called and a root node should be added |
1519 | 1518 |
/// with addSource() before using this function. |
1520 | 1519 |
/// |
1521 | 1520 |
/// \warning Contrary to \ref Bfs and \ref Dijkstra, \c am is an arc map, |
1522 | 1521 |
/// not a node map. |
1523 | 1522 |
template <typename AM> |
1524 | 1523 |
Arc start(const AM &am) { |
1525 | 1524 |
while ( !emptyQueue() && !am[_stack[_stack_head]] ) |
1526 | 1525 |
processNextArc(); |
1527 | 1526 |
return emptyQueue() ? INVALID : _stack[_stack_head]; |
1528 | 1527 |
} |
1529 | 1528 |
|
1530 | 1529 |
/// \brief Runs the algorithm from the given node. |
1531 | 1530 |
/// |
1532 | 1531 |
/// This method runs the %DFS algorithm from node \c s. |
1533 | 1532 |
/// in order to compute the DFS path to each node. |
1534 | 1533 |
/// |
1535 | 1534 |
/// The algorithm computes |
1536 | 1535 |
/// - the %DFS tree, |
1537 | 1536 |
/// - the distance of each node from the root in the %DFS tree. |
1538 | 1537 |
/// |
1539 | 1538 |
/// \note <tt>d.run(s)</tt> is just a shortcut of the following code. |
1540 | 1539 |
///\code |
1541 | 1540 |
/// d.init(); |
1542 | 1541 |
/// d.addSource(s); |
1543 | 1542 |
/// d.start(); |
1544 | 1543 |
///\endcode |
1545 | 1544 |
void run(Node s) { |
1546 | 1545 |
init(); |
1547 | 1546 |
addSource(s); |
1548 | 1547 |
start(); |
1549 | 1548 |
} |
1550 | 1549 |
|
1551 | 1550 |
/// \brief Finds the %DFS path between \c s and \c t. |
1552 | 1551 |
|
1553 | 1552 |
/// This method runs the %DFS algorithm from node \c s |
1554 | 1553 |
/// in order to compute the DFS path to \c t. |
1555 | 1554 |
/// |
1556 | 1555 |
/// \return The length of the <tt>s</tt>--<tt>t</tt> DFS path, |
1557 | 1556 |
/// if \c t is reachable form \c s, \c 0 otherwise. |
1558 | 1557 |
/// |
1559 | 1558 |
/// \note Apart from the return value, <tt>d.run(s,t)</tt> is |
1560 | 1559 |
/// just a shortcut of the following code. |
1561 | 1560 |
///\code |
1562 | 1561 |
/// d.init(); |
1563 | 1562 |
/// d.addSource(s); |
1564 | 1563 |
/// d.start(t); |
1565 | 1564 |
///\endcode |
1566 | 1565 |
int run(Node s,Node t) { |
1567 | 1566 |
init(); |
1568 | 1567 |
addSource(s); |
1569 | 1568 |
start(t); |
1570 | 1569 |
return reached(t)?_stack_head+1:0; |
1571 | 1570 |
} |
1572 | 1571 |
|
1573 | 1572 |
/// \brief Runs the algorithm to visit all nodes in the digraph. |
... | ... |
@@ -78,651 +78,650 @@ |
78 | 78 |
|
79 | 79 |
///Default traits class of Dijkstra class. |
80 | 80 |
|
81 | 81 |
///Default traits class of Dijkstra class. |
82 | 82 |
///\tparam GR The type of the digraph. |
83 | 83 |
///\tparam LM The type of the length map. |
84 | 84 |
template<class GR, class LM> |
85 | 85 |
struct DijkstraDefaultTraits |
86 | 86 |
{ |
87 | 87 |
///The type of the digraph the algorithm runs on. |
88 | 88 |
typedef GR Digraph; |
89 | 89 |
|
90 | 90 |
///The type of the map that stores the arc lengths. |
91 | 91 |
|
92 | 92 |
///The type of the map that stores the arc lengths. |
93 | 93 |
///It must meet the \ref concepts::ReadMap "ReadMap" concept. |
94 | 94 |
typedef LM LengthMap; |
95 | 95 |
///The type of the length of the arcs. |
96 | 96 |
typedef typename LM::Value Value; |
97 | 97 |
|
98 | 98 |
/// Operation traits for Dijkstra algorithm. |
99 | 99 |
|
100 | 100 |
/// This class defines the operations that are used in the algorithm. |
101 | 101 |
/// \see DijkstraDefaultOperationTraits |
102 | 102 |
typedef DijkstraDefaultOperationTraits<Value> OperationTraits; |
103 | 103 |
|
104 | 104 |
/// The cross reference type used by the heap. |
105 | 105 |
|
106 | 106 |
/// The cross reference type used by the heap. |
107 | 107 |
/// Usually it is \c Digraph::NodeMap<int>. |
108 | 108 |
typedef typename Digraph::template NodeMap<int> HeapCrossRef; |
109 | 109 |
///Instantiates a \ref HeapCrossRef. |
110 | 110 |
|
111 | 111 |
///This function instantiates a \ref HeapCrossRef. |
112 | 112 |
/// \param g is the digraph, to which we would like to define the |
113 | 113 |
/// \ref HeapCrossRef. |
114 | 114 |
static HeapCrossRef *createHeapCrossRef(const Digraph &g) |
115 | 115 |
{ |
116 | 116 |
return new HeapCrossRef(g); |
117 | 117 |
} |
118 | 118 |
|
119 | 119 |
///The heap type used by the Dijkstra algorithm. |
120 | 120 |
|
121 | 121 |
///The heap type used by the Dijkstra algorithm. |
122 | 122 |
/// |
123 | 123 |
///\sa BinHeap |
124 | 124 |
///\sa Dijkstra |
125 | 125 |
typedef BinHeap<typename LM::Value, HeapCrossRef, std::less<Value> > Heap; |
126 | 126 |
///Instantiates a \ref Heap. |
127 | 127 |
|
128 | 128 |
///This function instantiates a \ref Heap. |
129 | 129 |
static Heap *createHeap(HeapCrossRef& r) |
130 | 130 |
{ |
131 | 131 |
return new Heap(r); |
132 | 132 |
} |
133 | 133 |
|
134 | 134 |
///\brief The type of the map that stores the predecessor |
135 | 135 |
///arcs of the shortest paths. |
136 | 136 |
/// |
137 | 137 |
///The type of the map that stores the predecessor |
138 | 138 |
///arcs of the shortest paths. |
139 | 139 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
140 | 140 |
typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap; |
141 | 141 |
///Instantiates a \ref PredMap. |
142 | 142 |
|
143 | 143 |
///This function instantiates a \ref PredMap. |
144 | 144 |
///\param g is the digraph, to which we would like to define the |
145 | 145 |
///\ref PredMap. |
146 | 146 |
///\todo The digraph alone may be insufficient for the initialization |
147 | 147 |
static PredMap *createPredMap(const Digraph &g) |
148 | 148 |
{ |
149 | 149 |
return new PredMap(g); |
150 | 150 |
} |
151 | 151 |
|
152 | 152 |
///The type of the map that indicates which nodes are processed. |
153 | 153 |
|
154 | 154 |
///The type of the map that indicates which nodes are processed. |
155 | 155 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
156 | 156 |
///By default it is a NullMap. |
157 | 157 |
///\todo If it is set to a real map, |
158 | 158 |
///Dijkstra::processed() should read this. |
159 | 159 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
160 | 160 |
///Instantiates a \ref ProcessedMap. |
161 | 161 |
|
162 | 162 |
///This function instantiates a \ref ProcessedMap. |
163 | 163 |
///\param g is the digraph, to which |
164 | 164 |
///we would like to define the \ref ProcessedMap |
165 | 165 |
#ifdef DOXYGEN |
166 | 166 |
static ProcessedMap *createProcessedMap(const Digraph &g) |
167 | 167 |
#else |
168 | 168 |
static ProcessedMap *createProcessedMap(const Digraph &) |
169 | 169 |
#endif |
170 | 170 |
{ |
171 | 171 |
return new ProcessedMap(); |
172 | 172 |
} |
173 | 173 |
|
174 | 174 |
///The type of the map that stores the distances of the nodes. |
175 | 175 |
|
176 | 176 |
///The type of the map that stores the distances of the nodes. |
177 | 177 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
178 | 178 |
typedef typename Digraph::template NodeMap<typename LM::Value> DistMap; |
179 | 179 |
///Instantiates a \ref DistMap. |
180 | 180 |
|
181 | 181 |
///This function instantiates a \ref DistMap. |
182 | 182 |
///\param g is the digraph, to which we would like to define |
183 | 183 |
///the \ref DistMap |
184 | 184 |
static DistMap *createDistMap(const Digraph &g) |
185 | 185 |
{ |
186 | 186 |
return new DistMap(g); |
187 | 187 |
} |
188 | 188 |
}; |
189 | 189 |
|
190 | 190 |
///%Dijkstra algorithm class. |
191 | 191 |
|
192 | 192 |
/// \ingroup shortest_path |
193 | 193 |
///This class provides an efficient implementation of the %Dijkstra algorithm. |
194 | 194 |
/// |
195 | 195 |
///The arc lengths are passed to the algorithm using a |
196 | 196 |
///\ref concepts::ReadMap "ReadMap", |
197 | 197 |
///so it is easy to change it to any kind of length. |
198 | 198 |
///The type of the length is determined by the |
199 | 199 |
///\ref concepts::ReadMap::Value "Value" of the length map. |
200 | 200 |
///It is also possible to change the underlying priority heap. |
201 | 201 |
/// |
202 | 202 |
///There is also a \ref dijkstra() "function type interface" for the |
203 | 203 |
///%Dijkstra algorithm, which is convenient in the simplier cases and |
204 | 204 |
///it can be used easier. |
205 | 205 |
/// |
206 | 206 |
///\tparam GR The type of the digraph the algorithm runs on. |
207 | 207 |
///The default value is \ref ListDigraph. |
208 | 208 |
///The value of GR is not used directly by \ref Dijkstra, it is only |
209 | 209 |
///passed to \ref DijkstraDefaultTraits. |
210 | 210 |
///\tparam LM A readable arc map that determines the lengths of the |
211 | 211 |
///arcs. It is read once for each arc, so the map may involve in |
212 | 212 |
///relatively time consuming process to compute the arc lengths if |
213 | 213 |
///it is necessary. The default map type is \ref |
214 | 214 |
///concepts::Digraph::ArcMap "Digraph::ArcMap<int>". |
215 | 215 |
///The value of LM is not used directly by \ref Dijkstra, it is only |
216 | 216 |
///passed to \ref DijkstraDefaultTraits. |
217 | 217 |
///\tparam TR Traits class to set various data types used by the algorithm. |
218 | 218 |
///The default traits class is \ref DijkstraDefaultTraits |
219 | 219 |
///"DijkstraDefaultTraits<GR,LM>". See \ref DijkstraDefaultTraits |
220 | 220 |
///for the documentation of a Dijkstra traits class. |
221 | 221 |
#ifdef DOXYGEN |
222 | 222 |
template <typename GR, typename LM, typename TR> |
223 | 223 |
#else |
224 | 224 |
template <typename GR=ListDigraph, |
225 | 225 |
typename LM=typename GR::template ArcMap<int>, |
226 | 226 |
typename TR=DijkstraDefaultTraits<GR,LM> > |
227 | 227 |
#endif |
228 | 228 |
class Dijkstra { |
229 | 229 |
public: |
230 | 230 |
///\ref Exception for uninitialized parameters. |
231 | 231 |
|
232 | 232 |
///This error represents problems in the initialization of the |
233 | 233 |
///parameters of the algorithm. |
234 | 234 |
class UninitializedParameter : public lemon::UninitializedParameter { |
235 | 235 |
public: |
236 | 236 |
virtual const char* what() const throw() { |
237 | 237 |
return "lemon::Dijkstra::UninitializedParameter"; |
238 | 238 |
} |
239 | 239 |
}; |
240 | 240 |
|
241 | 241 |
///The type of the digraph the algorithm runs on. |
242 | 242 |
typedef typename TR::Digraph Digraph; |
243 | 243 |
|
244 | 244 |
///The type of the length of the arcs. |
245 | 245 |
typedef typename TR::LengthMap::Value Value; |
246 | 246 |
///The type of the map that stores the arc lengths. |
247 | 247 |
typedef typename TR::LengthMap LengthMap; |
248 | 248 |
///\brief The type of the map that stores the predecessor arcs of the |
249 | 249 |
///shortest paths. |
250 | 250 |
typedef typename TR::PredMap PredMap; |
251 | 251 |
///The type of the map that stores the distances of the nodes. |
252 | 252 |
typedef typename TR::DistMap DistMap; |
253 | 253 |
///The type of the map that indicates which nodes are processed. |
254 | 254 |
typedef typename TR::ProcessedMap ProcessedMap; |
255 | 255 |
///The type of the paths. |
256 | 256 |
typedef PredMapPath<Digraph, PredMap> Path; |
257 | 257 |
///The cross reference type used for the current heap. |
258 | 258 |
typedef typename TR::HeapCrossRef HeapCrossRef; |
259 | 259 |
///The heap type used by the algorithm. |
260 | 260 |
typedef typename TR::Heap Heap; |
261 | 261 |
///The operation traits class. |
262 | 262 |
typedef typename TR::OperationTraits OperationTraits; |
263 | 263 |
|
264 | 264 |
///The traits class. |
265 | 265 |
typedef TR Traits; |
266 | 266 |
|
267 | 267 |
private: |
268 | 268 |
|
269 | 269 |
typedef typename Digraph::Node Node; |
270 | 270 |
typedef typename Digraph::NodeIt NodeIt; |
271 | 271 |
typedef typename Digraph::Arc Arc; |
272 | 272 |
typedef typename Digraph::OutArcIt OutArcIt; |
273 | 273 |
|
274 | 274 |
//Pointer to the underlying digraph. |
275 | 275 |
const Digraph *G; |
276 | 276 |
//Pointer to the length map. |
277 | 277 |
const LengthMap *length; |
278 | 278 |
//Pointer to the map of predecessors arcs. |
279 | 279 |
PredMap *_pred; |
280 | 280 |
//Indicates if _pred is locally allocated (true) or not. |
281 | 281 |
bool local_pred; |
282 | 282 |
//Pointer to the map of distances. |
283 | 283 |
DistMap *_dist; |
284 | 284 |
//Indicates if _dist is locally allocated (true) or not. |
285 | 285 |
bool local_dist; |
286 | 286 |
//Pointer to the map of processed status of the nodes. |
287 | 287 |
ProcessedMap *_processed; |
288 | 288 |
//Indicates if _processed is locally allocated (true) or not. |
289 | 289 |
bool local_processed; |
290 | 290 |
//Pointer to the heap cross references. |
291 | 291 |
HeapCrossRef *_heap_cross_ref; |
292 | 292 |
//Indicates if _heap_cross_ref is locally allocated (true) or not. |
293 | 293 |
bool local_heap_cross_ref; |
294 | 294 |
//Pointer to the heap. |
295 | 295 |
Heap *_heap; |
296 | 296 |
//Indicates if _heap is locally allocated (true) or not. |
297 | 297 |
bool local_heap; |
298 | 298 |
|
299 | 299 |
///Creates the maps if necessary. |
300 | 300 |
///\todo Better memory allocation (instead of new). |
301 | 301 |
void create_maps() |
302 | 302 |
{ |
303 | 303 |
if(!_pred) { |
304 | 304 |
local_pred = true; |
305 | 305 |
_pred = Traits::createPredMap(*G); |
306 | 306 |
} |
307 | 307 |
if(!_dist) { |
308 | 308 |
local_dist = true; |
309 | 309 |
_dist = Traits::createDistMap(*G); |
310 | 310 |
} |
311 | 311 |
if(!_processed) { |
312 | 312 |
local_processed = true; |
313 | 313 |
_processed = Traits::createProcessedMap(*G); |
314 | 314 |
} |
315 | 315 |
if (!_heap_cross_ref) { |
316 | 316 |
local_heap_cross_ref = true; |
317 | 317 |
_heap_cross_ref = Traits::createHeapCrossRef(*G); |
318 | 318 |
} |
319 | 319 |
if (!_heap) { |
320 | 320 |
local_heap = true; |
321 | 321 |
_heap = Traits::createHeap(*_heap_cross_ref); |
322 | 322 |
} |
323 | 323 |
} |
324 | 324 |
|
325 | 325 |
public: |
326 | 326 |
|
327 | 327 |
typedef Dijkstra Create; |
328 | 328 |
|
329 | 329 |
///\name Named template parameters |
330 | 330 |
|
331 | 331 |
///@{ |
332 | 332 |
|
333 | 333 |
template <class T> |
334 |
struct |
|
334 |
struct SetPredMapTraits : public Traits { |
|
335 | 335 |
typedef T PredMap; |
336 | 336 |
static PredMap *createPredMap(const Digraph &) |
337 | 337 |
{ |
338 | 338 |
throw UninitializedParameter(); |
339 | 339 |
} |
340 | 340 |
}; |
341 | 341 |
///\brief \ref named-templ-param "Named parameter" for setting |
342 | 342 |
///\ref PredMap type. |
343 | 343 |
/// |
344 | 344 |
///\ref named-templ-param "Named parameter" for setting |
345 | 345 |
///\ref PredMap type. |
346 | 346 |
template <class T> |
347 |
struct DefPredMap |
|
348 |
: public Dijkstra< Digraph, LengthMap, DefPredMapTraits<T> > { |
|
349 |
|
|
347 |
struct SetPredMap |
|
348 |
: public Dijkstra< Digraph, LengthMap, SetPredMapTraits<T> > { |
|
349 |
typedef Dijkstra< Digraph, LengthMap, SetPredMapTraits<T> > Create; |
|
350 | 350 |
}; |
351 | 351 |
|
352 | 352 |
template <class T> |
353 |
struct |
|
353 |
struct SetDistMapTraits : public Traits { |
|
354 | 354 |
typedef T DistMap; |
355 | 355 |
static DistMap *createDistMap(const Digraph &) |
356 | 356 |
{ |
357 | 357 |
throw UninitializedParameter(); |
358 | 358 |
} |
359 | 359 |
}; |
360 | 360 |
///\brief \ref named-templ-param "Named parameter" for setting |
361 | 361 |
///\ref DistMap type. |
362 | 362 |
/// |
363 | 363 |
///\ref named-templ-param "Named parameter" for setting |
364 | 364 |
///\ref DistMap type. |
365 | 365 |
template <class T> |
366 |
struct DefDistMap |
|
367 |
: public Dijkstra< Digraph, LengthMap, DefDistMapTraits<T> > { |
|
368 |
|
|
366 |
struct SetDistMap |
|
367 |
: public Dijkstra< Digraph, LengthMap, SetDistMapTraits<T> > { |
|
368 |
typedef Dijkstra< Digraph, LengthMap, SetDistMapTraits<T> > Create; |
|
369 | 369 |
}; |
370 | 370 |
|
371 | 371 |
template <class T> |
372 |
struct |
|
372 |
struct SetProcessedMapTraits : public Traits { |
|
373 | 373 |
typedef T ProcessedMap; |
374 | 374 |
static ProcessedMap *createProcessedMap(const Digraph &) |
375 | 375 |
{ |
376 | 376 |
throw UninitializedParameter(); |
377 | 377 |
} |
378 | 378 |
}; |
379 | 379 |
///\brief \ref named-templ-param "Named parameter" for setting |
380 | 380 |
///\ref ProcessedMap type. |
381 | 381 |
/// |
382 | 382 |
///\ref named-templ-param "Named parameter" for setting |
383 | 383 |
///\ref ProcessedMap type. |
384 | 384 |
template <class T> |
385 |
struct DefProcessedMap |
|
386 |
: public Dijkstra< Digraph, LengthMap, DefProcessedMapTraits<T> > { |
|
387 |
|
|
385 |
struct SetProcessedMap |
|
386 |
: public Dijkstra< Digraph, LengthMap, SetProcessedMapTraits<T> > { |
|
387 |
typedef Dijkstra< Digraph, LengthMap, SetProcessedMapTraits<T> > Create; |
|
388 | 388 |
}; |
389 | 389 |
|
390 |
struct |
|
390 |
struct SetStandardProcessedMapTraits : public Traits { |
|
391 | 391 |
typedef typename Digraph::template NodeMap<bool> ProcessedMap; |
392 | 392 |
static ProcessedMap *createProcessedMap(const Digraph &g) |
393 | 393 |
{ |
394 | 394 |
return new ProcessedMap(g); |
395 | 395 |
} |
396 | 396 |
}; |
397 | 397 |
///\brief \ref named-templ-param "Named parameter" for setting |
398 | 398 |
///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>. |
399 | 399 |
/// |
400 | 400 |
///\ref named-templ-param "Named parameter" for setting |
401 | 401 |
///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>. |
402 | 402 |
///If you don't set it explicitly, it will be automatically allocated. |
403 |
template <class T> |
|
404 |
struct DefProcessedMapToBeDefaultMap |
|
405 |
: public Dijkstra< Digraph, LengthMap, DefDigraphProcessedMapTraits> { |
|
406 |
typedef Dijkstra< Digraph, LengthMap, DefDigraphProcessedMapTraits> |
|
403 |
struct SetStandardProcessedMap |
|
404 |
: public Dijkstra< Digraph, LengthMap, SetStandardProcessedMapTraits > { |
|
405 |
typedef Dijkstra< Digraph, LengthMap, SetStandardProcessedMapTraits > |
|
407 | 406 |
Create; |
408 | 407 |
}; |
409 | 408 |
|
410 | 409 |
template <class H, class CR> |
411 |
struct |
|
410 |
struct SetHeapTraits : public Traits { |
|
412 | 411 |
typedef CR HeapCrossRef; |
413 | 412 |
typedef H Heap; |
414 | 413 |
static HeapCrossRef *createHeapCrossRef(const Digraph &) { |
415 | 414 |
throw UninitializedParameter(); |
416 | 415 |
} |
417 | 416 |
static Heap *createHeap(HeapCrossRef &) |
418 | 417 |
{ |
419 | 418 |
throw UninitializedParameter(); |
420 | 419 |
} |
421 | 420 |
}; |
422 | 421 |
///\brief \ref named-templ-param "Named parameter" for setting |
423 | 422 |
///heap and cross reference type |
424 | 423 |
/// |
425 | 424 |
///\ref named-templ-param "Named parameter" for setting heap and cross |
426 | 425 |
///reference type. |
427 | 426 |
template <class H, class CR = typename Digraph::template NodeMap<int> > |
428 |
struct DefHeap |
|
429 |
: public Dijkstra< Digraph, LengthMap, DefHeapTraits<H, CR> > { |
|
430 |
|
|
427 |
struct SetHeap |
|
428 |
: public Dijkstra< Digraph, LengthMap, SetHeapTraits<H, CR> > { |
|
429 |
typedef Dijkstra< Digraph, LengthMap, SetHeapTraits<H, CR> > Create; |
|
431 | 430 |
}; |
432 | 431 |
|
433 | 432 |
template <class H, class CR> |
434 |
struct |
|
433 |
struct SetStandardHeapTraits : public Traits { |
|
435 | 434 |
typedef CR HeapCrossRef; |
436 | 435 |
typedef H Heap; |
437 | 436 |
static HeapCrossRef *createHeapCrossRef(const Digraph &G) { |
438 | 437 |
return new HeapCrossRef(G); |
439 | 438 |
} |
440 | 439 |
static Heap *createHeap(HeapCrossRef &R) |
441 | 440 |
{ |
442 | 441 |
return new Heap(R); |
443 | 442 |
} |
444 | 443 |
}; |
445 | 444 |
///\brief \ref named-templ-param "Named parameter" for setting |
446 | 445 |
///heap and cross reference type with automatic allocation |
447 | 446 |
/// |
448 | 447 |
///\ref named-templ-param "Named parameter" for setting heap and cross |
449 | 448 |
///reference type. It can allocate the heap and the cross reference |
450 | 449 |
///object if the cross reference's constructor waits for the digraph as |
451 | 450 |
///parameter and the heap's constructor waits for the cross reference. |
452 | 451 |
template <class H, class CR = typename Digraph::template NodeMap<int> > |
453 |
struct DefStandardHeap |
|
454 |
: public Dijkstra< Digraph, LengthMap, DefStandardHeapTraits<H, CR> > { |
|
455 |
|
|
452 |
struct SetStandardHeap |
|
453 |
: public Dijkstra< Digraph, LengthMap, SetStandardHeapTraits<H, CR> > { |
|
454 |
typedef Dijkstra< Digraph, LengthMap, SetStandardHeapTraits<H, CR> > |
|
456 | 455 |
Create; |
457 | 456 |
}; |
458 | 457 |
|
459 | 458 |
template <class T> |
460 |
struct |
|
459 |
struct SetOperationTraitsTraits : public Traits { |
|
461 | 460 |
typedef T OperationTraits; |
462 | 461 |
}; |
463 | 462 |
|
464 | 463 |
/// \brief \ref named-templ-param "Named parameter" for setting |
465 | 464 |
///\ref OperationTraits type |
466 | 465 |
/// |
467 | 466 |
///\ref named-templ-param "Named parameter" for setting |
468 | 467 |
///\ref OperationTraits type. |
469 | 468 |
template <class T> |
470 |
struct DefOperationTraits |
|
471 |
: public Dijkstra<Digraph, LengthMap, DefOperationTraitsTraits<T> > { |
|
472 |
|
|
469 |
struct SetOperationTraits |
|
470 |
: public Dijkstra<Digraph, LengthMap, SetOperationTraitsTraits<T> > { |
|
471 |
typedef Dijkstra<Digraph, LengthMap, SetOperationTraitsTraits<T> > |
|
473 | 472 |
Create; |
474 | 473 |
}; |
475 | 474 |
|
476 | 475 |
///@} |
477 | 476 |
|
478 | 477 |
protected: |
479 | 478 |
|
480 | 479 |
Dijkstra() {} |
481 | 480 |
|
482 | 481 |
public: |
483 | 482 |
|
484 | 483 |
///Constructor. |
485 | 484 |
|
486 | 485 |
///Constructor. |
487 | 486 |
///\param _g The digraph the algorithm runs on. |
488 | 487 |
///\param _length The length map used by the algorithm. |
489 | 488 |
Dijkstra(const Digraph& _g, const LengthMap& _length) : |
490 | 489 |
G(&_g), length(&_length), |
491 | 490 |
_pred(NULL), local_pred(false), |
492 | 491 |
_dist(NULL), local_dist(false), |
493 | 492 |
_processed(NULL), local_processed(false), |
494 | 493 |
_heap_cross_ref(NULL), local_heap_cross_ref(false), |
495 | 494 |
_heap(NULL), local_heap(false) |
496 | 495 |
{ } |
497 | 496 |
|
498 | 497 |
///Destructor. |
499 | 498 |
~Dijkstra() |
500 | 499 |
{ |
501 | 500 |
if(local_pred) delete _pred; |
502 | 501 |
if(local_dist) delete _dist; |
503 | 502 |
if(local_processed) delete _processed; |
504 | 503 |
if(local_heap_cross_ref) delete _heap_cross_ref; |
505 | 504 |
if(local_heap) delete _heap; |
506 | 505 |
} |
507 | 506 |
|
508 | 507 |
///Sets the length map. |
509 | 508 |
|
510 | 509 |
///Sets the length map. |
511 | 510 |
///\return <tt> (*this) </tt> |
512 | 511 |
Dijkstra &lengthMap(const LengthMap &m) |
513 | 512 |
{ |
514 | 513 |
length = &m; |
515 | 514 |
return *this; |
516 | 515 |
} |
517 | 516 |
|
518 | 517 |
///Sets the map that stores the predecessor arcs. |
519 | 518 |
|
520 | 519 |
///Sets the map that stores the predecessor arcs. |
521 | 520 |
///If you don't use this function before calling \ref run(), |
522 | 521 |
///it will allocate one. The destructor deallocates this |
523 | 522 |
///automatically allocated map, of course. |
524 | 523 |
///\return <tt> (*this) </tt> |
525 | 524 |
Dijkstra &predMap(PredMap &m) |
526 | 525 |
{ |
527 | 526 |
if(local_pred) { |
528 | 527 |
delete _pred; |
529 | 528 |
local_pred=false; |
530 | 529 |
} |
531 | 530 |
_pred = &m; |
532 | 531 |
return *this; |
533 | 532 |
} |
534 | 533 |
|
535 | 534 |
///Sets the map that indicates which nodes are processed. |
536 | 535 |
|
537 | 536 |
///Sets the map that indicates which nodes are processed. |
538 | 537 |
///If you don't use this function before calling \ref run(), |
539 | 538 |
///it will allocate one. The destructor deallocates this |
540 | 539 |
///automatically allocated map, of course. |
541 | 540 |
///\return <tt> (*this) </tt> |
542 | 541 |
Dijkstra &processedMap(ProcessedMap &m) |
543 | 542 |
{ |
544 | 543 |
if(local_processed) { |
545 | 544 |
delete _processed; |
546 | 545 |
local_processed=false; |
547 | 546 |
} |
548 | 547 |
_processed = &m; |
549 | 548 |
return *this; |
550 | 549 |
} |
551 | 550 |
|
552 | 551 |
///Sets the map that stores the distances of the nodes. |
553 | 552 |
|
554 | 553 |
///Sets the map that stores the distances of the nodes calculated by the |
555 | 554 |
///algorithm. |
556 | 555 |
///If you don't use this function before calling \ref run(), |
557 | 556 |
///it will allocate one. The destructor deallocates this |
558 | 557 |
///automatically allocated map, of course. |
559 | 558 |
///\return <tt> (*this) </tt> |
560 | 559 |
Dijkstra &distMap(DistMap &m) |
561 | 560 |
{ |
562 | 561 |
if(local_dist) { |
563 | 562 |
delete _dist; |
564 | 563 |
local_dist=false; |
565 | 564 |
} |
566 | 565 |
_dist = &m; |
567 | 566 |
return *this; |
568 | 567 |
} |
569 | 568 |
|
570 | 569 |
///Sets the heap and the cross reference used by algorithm. |
571 | 570 |
|
572 | 571 |
///Sets the heap and the cross reference used by algorithm. |
573 | 572 |
///If you don't use this function before calling \ref run(), |
574 | 573 |
///it will allocate one. The destructor deallocates this |
575 | 574 |
///automatically allocated heap and cross reference, of course. |
576 | 575 |
///\return <tt> (*this) </tt> |
577 | 576 |
Dijkstra &heap(Heap& hp, HeapCrossRef &cr) |
578 | 577 |
{ |
579 | 578 |
if(local_heap_cross_ref) { |
580 | 579 |
delete _heap_cross_ref; |
581 | 580 |
local_heap_cross_ref=false; |
582 | 581 |
} |
583 | 582 |
_heap_cross_ref = &cr; |
584 | 583 |
if(local_heap) { |
585 | 584 |
delete _heap; |
586 | 585 |
local_heap=false; |
587 | 586 |
} |
588 | 587 |
_heap = &hp; |
589 | 588 |
return *this; |
590 | 589 |
} |
591 | 590 |
|
592 | 591 |
private: |
593 | 592 |
|
594 | 593 |
void finalizeNodeData(Node v,Value dst) |
595 | 594 |
{ |
596 | 595 |
_processed->set(v,true); |
597 | 596 |
_dist->set(v, dst); |
598 | 597 |
} |
599 | 598 |
|
600 | 599 |
public: |
601 | 600 |
|
602 | 601 |
///\name Execution control |
603 | 602 |
///The simplest way to execute the algorithm is to use one of the |
604 | 603 |
///member functions called \ref lemon::Dijkstra::run() "run()". |
605 | 604 |
///\n |
606 | 605 |
///If you need more control on the execution, first you must call |
607 | 606 |
///\ref lemon::Dijkstra::init() "init()", then you can add several |
608 | 607 |
///source nodes with \ref lemon::Dijkstra::addSource() "addSource()". |
609 | 608 |
///Finally \ref lemon::Dijkstra::start() "start()" will perform the |
610 | 609 |
///actual path computation. |
611 | 610 |
|
612 | 611 |
///@{ |
613 | 612 |
|
614 | 613 |
///Initializes the internal data structures. |
615 | 614 |
|
616 | 615 |
///Initializes the internal data structures. |
617 | 616 |
/// |
618 | 617 |
void init() |
619 | 618 |
{ |
620 | 619 |
create_maps(); |
621 | 620 |
_heap->clear(); |
622 | 621 |
for ( NodeIt u(*G) ; u!=INVALID ; ++u ) { |
623 | 622 |
_pred->set(u,INVALID); |
624 | 623 |
_processed->set(u,false); |
625 | 624 |
_heap_cross_ref->set(u,Heap::PRE_HEAP); |
626 | 625 |
} |
627 | 626 |
} |
628 | 627 |
|
629 | 628 |
///Adds a new source node. |
630 | 629 |
|
631 | 630 |
///Adds a new source node to the priority heap. |
632 | 631 |
///The optional second parameter is the initial distance of the node. |
633 | 632 |
/// |
634 | 633 |
///The function checks if the node has already been added to the heap and |
635 | 634 |
///it is pushed to the heap only if either it was not in the heap |
636 | 635 |
///or the shortest path found till then is shorter than \c dst. |
637 | 636 |
void addSource(Node s,Value dst=OperationTraits::zero()) |
638 | 637 |
{ |
639 | 638 |
if(_heap->state(s) != Heap::IN_HEAP) { |
640 | 639 |
_heap->push(s,dst); |
641 | 640 |
} else if(OperationTraits::less((*_heap)[s], dst)) { |
642 | 641 |
_heap->set(s,dst); |
643 | 642 |
_pred->set(s,INVALID); |
644 | 643 |
} |
645 | 644 |
} |
646 | 645 |
|
647 | 646 |
///Processes the next node in the priority heap |
648 | 647 |
|
649 | 648 |
///Processes the next node in the priority heap. |
650 | 649 |
/// |
651 | 650 |
///\return The processed node. |
652 | 651 |
/// |
653 | 652 |
///\warning The priority heap must not be empty. |
654 | 653 |
Node processNextNode() |
655 | 654 |
{ |
656 | 655 |
Node v=_heap->top(); |
657 | 656 |
Value oldvalue=_heap->prio(); |
658 | 657 |
_heap->pop(); |
659 | 658 |
finalizeNodeData(v,oldvalue); |
660 | 659 |
|
661 | 660 |
for(OutArcIt e(*G,v); e!=INVALID; ++e) { |
662 | 661 |
Node w=G->target(e); |
663 | 662 |
switch(_heap->state(w)) { |
664 | 663 |
case Heap::PRE_HEAP: |
665 | 664 |
_heap->push(w,OperationTraits::plus(oldvalue, (*length)[e])); |
666 | 665 |
_pred->set(w,e); |
667 | 666 |
break; |
668 | 667 |
case Heap::IN_HEAP: |
669 | 668 |
{ |
670 | 669 |
Value newvalue = OperationTraits::plus(oldvalue, (*length)[e]); |
671 | 670 |
if ( OperationTraits::less(newvalue, (*_heap)[w]) ) { |
672 | 671 |
_heap->decrease(w, newvalue); |
673 | 672 |
_pred->set(w,e); |
674 | 673 |
} |
675 | 674 |
} |
676 | 675 |
break; |
677 | 676 |
case Heap::POST_HEAP: |
678 | 677 |
break; |
679 | 678 |
} |
680 | 679 |
} |
681 | 680 |
return v; |
682 | 681 |
} |
683 | 682 |
|
684 | 683 |
///The next node to be processed. |
685 | 684 |
|
686 | 685 |
///Returns the next node to be processed or \c INVALID if the |
687 | 686 |
///priority heap is empty. |
688 | 687 |
Node nextNode() const |
689 | 688 |
{ |
690 | 689 |
return !_heap->empty()?_heap->top():INVALID; |
691 | 690 |
} |
692 | 691 |
|
693 | 692 |
///\brief Returns \c false if there are nodes |
694 | 693 |
///to be processed. |
695 | 694 |
/// |
696 | 695 |
///Returns \c false if there are nodes |
697 | 696 |
///to be processed in the priority heap. |
698 | 697 |
bool emptyQueue() const { return _heap->empty(); } |
699 | 698 |
|
700 | 699 |
///Returns the number of the nodes to be processed in the priority heap |
701 | 700 |
|
702 | 701 |
///Returns the number of the nodes to be processed in the priority heap. |
703 | 702 |
/// |
704 | 703 |
int queueSize() const { return _heap->size(); } |
705 | 704 |
|
706 | 705 |
///Executes the algorithm. |
707 | 706 |
|
708 | 707 |
///Executes the algorithm. |
709 | 708 |
/// |
710 | 709 |
///This method runs the %Dijkstra algorithm from the root node(s) |
711 | 710 |
///in order to compute the shortest path to each node. |
712 | 711 |
/// |
713 | 712 |
///The algorithm computes |
714 | 713 |
///- the shortest path tree (forest), |
715 | 714 |
///- the distance of each node from the root(s). |
716 | 715 |
/// |
717 | 716 |
///\pre init() must be called and at least one root node should be |
718 | 717 |
///added with addSource() before using this function. |
719 | 718 |
/// |
720 | 719 |
///\note <tt>d.start()</tt> is just a shortcut of the following code. |
721 | 720 |
///\code |
722 | 721 |
/// while ( !d.emptyQueue() ) { |
723 | 722 |
/// d.processNextNode(); |
724 | 723 |
/// } |
725 | 724 |
///\endcode |
726 | 725 |
void start() |
727 | 726 |
{ |
728 | 727 |
while ( !emptyQueue() ) processNextNode(); |
... | ... |
@@ -952,338 +951,338 @@ |
952 | 951 |
|
953 | 952 |
/// The cross reference type used by the heap. |
954 | 953 |
/// Usually it is \c Digraph::NodeMap<int>. |
955 | 954 |
typedef typename Digraph::template NodeMap<int> HeapCrossRef; |
956 | 955 |
///Instantiates a \ref HeapCrossRef. |
957 | 956 |
|
958 | 957 |
///This function instantiates a \ref HeapCrossRef. |
959 | 958 |
/// \param g is the digraph, to which we would like to define the |
960 | 959 |
/// HeapCrossRef. |
961 | 960 |
/// \todo The digraph alone may be insufficient for the initialization |
962 | 961 |
static HeapCrossRef *createHeapCrossRef(const Digraph &g) |
963 | 962 |
{ |
964 | 963 |
return new HeapCrossRef(g); |
965 | 964 |
} |
966 | 965 |
|
967 | 966 |
///The heap type used by the Dijkstra algorithm. |
968 | 967 |
|
969 | 968 |
///The heap type used by the Dijkstra algorithm. |
970 | 969 |
/// |
971 | 970 |
///\sa BinHeap |
972 | 971 |
///\sa Dijkstra |
973 | 972 |
typedef BinHeap<Value, typename Digraph::template NodeMap<int>, |
974 | 973 |
std::less<Value> > Heap; |
975 | 974 |
|
976 | 975 |
///Instantiates a \ref Heap. |
977 | 976 |
|
978 | 977 |
///This function instantiates a \ref Heap. |
979 | 978 |
/// \param r is the HeapCrossRef which is used. |
980 | 979 |
static Heap *createHeap(HeapCrossRef& r) |
981 | 980 |
{ |
982 | 981 |
return new Heap(r); |
983 | 982 |
} |
984 | 983 |
|
985 | 984 |
///\brief The type of the map that stores the predecessor |
986 | 985 |
///arcs of the shortest paths. |
987 | 986 |
/// |
988 | 987 |
///The type of the map that stores the predecessor |
989 | 988 |
///arcs of the shortest paths. |
990 | 989 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
991 | 990 |
typedef NullMap <typename Digraph::Node,typename Digraph::Arc> PredMap; |
992 | 991 |
///Instantiates a \ref PredMap. |
993 | 992 |
|
994 | 993 |
///This function instantiates a \ref PredMap. |
995 | 994 |
///\param g is the digraph, to which we would like to define the |
996 | 995 |
///\ref PredMap. |
997 | 996 |
///\todo The digraph alone may be insufficient to initialize |
998 | 997 |
#ifdef DOXYGEN |
999 | 998 |
static PredMap *createPredMap(const Digraph &g) |
1000 | 999 |
#else |
1001 | 1000 |
static PredMap *createPredMap(const Digraph &) |
1002 | 1001 |
#endif |
1003 | 1002 |
{ |
1004 | 1003 |
return new PredMap(); |
1005 | 1004 |
} |
1006 | 1005 |
|
1007 | 1006 |
///The type of the map that indicates which nodes are processed. |
1008 | 1007 |
|
1009 | 1008 |
///The type of the map that indicates which nodes are processed. |
1010 | 1009 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
1011 | 1010 |
///By default it is a NullMap. |
1012 | 1011 |
///\todo If it is set to a real map, |
1013 | 1012 |
///Dijkstra::processed() should read this. |
1014 | 1013 |
///\todo named parameter to set this type, function to read and write. |
1015 | 1014 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
1016 | 1015 |
///Instantiates a \ref ProcessedMap. |
1017 | 1016 |
|
1018 | 1017 |
///This function instantiates a \ref ProcessedMap. |
1019 | 1018 |
///\param g is the digraph, to which |
1020 | 1019 |
///we would like to define the \ref ProcessedMap. |
1021 | 1020 |
#ifdef DOXYGEN |
1022 | 1021 |
static ProcessedMap *createProcessedMap(const Digraph &g) |
1023 | 1022 |
#else |
1024 | 1023 |
static ProcessedMap *createProcessedMap(const Digraph &) |
1025 | 1024 |
#endif |
1026 | 1025 |
{ |
1027 | 1026 |
return new ProcessedMap(); |
1028 | 1027 |
} |
1029 | 1028 |
|
1030 | 1029 |
///The type of the map that stores the distances of the nodes. |
1031 | 1030 |
|
1032 | 1031 |
///The type of the map that stores the distances of the nodes. |
1033 | 1032 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
1034 | 1033 |
typedef NullMap<typename Digraph::Node,Value> DistMap; |
1035 | 1034 |
///Instantiates a \ref DistMap. |
1036 | 1035 |
|
1037 | 1036 |
///This function instantiates a \ref DistMap. |
1038 | 1037 |
///\param g is the digraph, to which we would like to define |
1039 | 1038 |
///the \ref DistMap |
1040 | 1039 |
#ifdef DOXYGEN |
1041 | 1040 |
static DistMap *createDistMap(const Digraph &g) |
1042 | 1041 |
#else |
1043 | 1042 |
static DistMap *createDistMap(const Digraph &) |
1044 | 1043 |
#endif |
1045 | 1044 |
{ |
1046 | 1045 |
return new DistMap(); |
1047 | 1046 |
} |
1048 | 1047 |
}; |
1049 | 1048 |
|
1050 | 1049 |
/// Default traits class used by \ref DijkstraWizard |
1051 | 1050 |
|
1052 | 1051 |
/// To make it easier to use Dijkstra algorithm |
1053 | 1052 |
/// we have created a wizard class. |
1054 | 1053 |
/// This \ref DijkstraWizard class needs default traits, |
1055 | 1054 |
/// as well as the \ref Dijkstra class. |
1056 | 1055 |
/// The \ref DijkstraWizardBase is a class to be the default traits of the |
1057 | 1056 |
/// \ref DijkstraWizard class. |
1058 | 1057 |
/// \todo More named parameters are required... |
1059 | 1058 |
template<class GR,class LM> |
1060 | 1059 |
class DijkstraWizardBase : public DijkstraWizardDefaultTraits<GR,LM> |
1061 | 1060 |
{ |
1062 | 1061 |
typedef DijkstraWizardDefaultTraits<GR,LM> Base; |
1063 | 1062 |
protected: |
1064 | 1063 |
//The type of the nodes in the digraph. |
1065 | 1064 |
typedef typename Base::Digraph::Node Node; |
1066 | 1065 |
|
1067 | 1066 |
//Pointer to the digraph the algorithm runs on. |
1068 | 1067 |
void *_g; |
1069 | 1068 |
//Pointer to the length map |
1070 | 1069 |
void *_length; |
1071 | 1070 |
//Pointer to the map of processed nodes. |
1072 | 1071 |
void *_processed; |
1073 | 1072 |
//Pointer to the map of predecessors arcs. |
1074 | 1073 |
void *_pred; |
1075 | 1074 |
//Pointer to the map of distances. |
1076 | 1075 |
void *_dist; |
1077 | 1076 |
//Pointer to the source node. |
1078 | 1077 |
Node _source; |
1079 | 1078 |
|
1080 | 1079 |
public: |
1081 | 1080 |
/// Constructor. |
1082 | 1081 |
|
1083 | 1082 |
/// This constructor does not require parameters, therefore it initiates |
1084 | 1083 |
/// all of the attributes to default values (0, INVALID). |
1085 | 1084 |
DijkstraWizardBase() : _g(0), _length(0), _processed(0), _pred(0), |
1086 | 1085 |
_dist(0), _source(INVALID) {} |
1087 | 1086 |
|
1088 | 1087 |
/// Constructor. |
1089 | 1088 |
|
1090 | 1089 |
/// This constructor requires some parameters, |
1091 | 1090 |
/// listed in the parameters list. |
1092 | 1091 |
/// Others are initiated to 0. |
1093 | 1092 |
/// \param g The digraph the algorithm runs on. |
1094 | 1093 |
/// \param l The length map. |
1095 | 1094 |
/// \param s The source node. |
1096 | 1095 |
DijkstraWizardBase(const GR &g,const LM &l, Node s=INVALID) : |
1097 | 1096 |
_g(reinterpret_cast<void*>(const_cast<GR*>(&g))), |
1098 | 1097 |
_length(reinterpret_cast<void*>(const_cast<LM*>(&l))), |
1099 | 1098 |
_processed(0), _pred(0), _dist(0), _source(s) {} |
1100 | 1099 |
|
1101 | 1100 |
}; |
1102 | 1101 |
|
1103 | 1102 |
/// Auxiliary class for the function type interface of Dijkstra algorithm. |
1104 | 1103 |
|
1105 | 1104 |
/// This auxiliary class is created to implement the function type |
1106 | 1105 |
/// interface of \ref Dijkstra algorithm. It uses the functions and features |
1107 | 1106 |
/// of the plain \ref Dijkstra, but it is much simpler to use it. |
1108 | 1107 |
/// It should only be used through the \ref dijkstra() function, which makes |
1109 | 1108 |
/// it easier to use the algorithm. |
1110 | 1109 |
/// |
1111 | 1110 |
/// Simplicity means that the way to change the types defined |
1112 | 1111 |
/// in the traits class is based on functions that returns the new class |
1113 | 1112 |
/// and not on templatable built-in classes. |
1114 | 1113 |
/// When using the plain \ref Dijkstra |
1115 | 1114 |
/// the new class with the modified type comes from |
1116 | 1115 |
/// the original class by using the :: |
1117 | 1116 |
/// operator. In the case of \ref DijkstraWizard only |
1118 | 1117 |
/// a function have to be called, and it will |
1119 | 1118 |
/// return the needed class. |
1120 | 1119 |
/// |
1121 | 1120 |
/// It does not have own \ref run() method. When its \ref run() method |
1122 | 1121 |
/// is called, it initiates a plain \ref Dijkstra object, and calls the |
1123 | 1122 |
/// \ref Dijkstra::run() method of it. |
1124 | 1123 |
template<class TR> |
1125 | 1124 |
class DijkstraWizard : public TR |
1126 | 1125 |
{ |
1127 | 1126 |
typedef TR Base; |
1128 | 1127 |
|
1129 | 1128 |
///The type of the digraph the algorithm runs on. |
1130 | 1129 |
typedef typename TR::Digraph Digraph; |
1131 | 1130 |
|
1132 | 1131 |
typedef typename Digraph::Node Node; |
1133 | 1132 |
typedef typename Digraph::NodeIt NodeIt; |
1134 | 1133 |
typedef typename Digraph::Arc Arc; |
1135 | 1134 |
typedef typename Digraph::OutArcIt OutArcIt; |
1136 | 1135 |
|
1137 | 1136 |
///The type of the map that stores the arc lengths. |
1138 | 1137 |
typedef typename TR::LengthMap LengthMap; |
1139 | 1138 |
///The type of the length of the arcs. |
1140 | 1139 |
typedef typename LengthMap::Value Value; |
1141 | 1140 |
///\brief The type of the map that stores the predecessor |
1142 | 1141 |
///arcs of the shortest paths. |
1143 | 1142 |
typedef typename TR::PredMap PredMap; |
1144 | 1143 |
///The type of the map that stores the distances of the nodes. |
1145 | 1144 |
typedef typename TR::DistMap DistMap; |
1146 | 1145 |
///The type of the map that indicates which nodes are processed. |
1147 | 1146 |
typedef typename TR::ProcessedMap ProcessedMap; |
1148 | 1147 |
///The heap type used by the dijkstra algorithm. |
1149 | 1148 |
typedef typename TR::Heap Heap; |
1150 | 1149 |
|
1151 | 1150 |
public: |
1152 | 1151 |
|
1153 | 1152 |
/// Constructor. |
1154 | 1153 |
DijkstraWizard() : TR() {} |
1155 | 1154 |
|
1156 | 1155 |
/// Constructor that requires parameters. |
1157 | 1156 |
|
1158 | 1157 |
/// Constructor that requires parameters. |
1159 | 1158 |
/// These parameters will be the default values for the traits class. |
1160 | 1159 |
DijkstraWizard(const Digraph &g,const LengthMap &l, Node s=INVALID) : |
1161 | 1160 |
TR(g,l,s) {} |
1162 | 1161 |
|
1163 | 1162 |
///Copy constructor |
1164 | 1163 |
DijkstraWizard(const TR &b) : TR(b) {} |
1165 | 1164 |
|
1166 | 1165 |
~DijkstraWizard() {} |
1167 | 1166 |
|
1168 | 1167 |
///Runs Dijkstra algorithm from a source node. |
1169 | 1168 |
|
1170 | 1169 |
///Runs Dijkstra algorithm from a source node. |
1171 | 1170 |
///The node can be given with the \ref source() function. |
1172 | 1171 |
void run() |
1173 | 1172 |
{ |
1174 | 1173 |
if(Base::_source==INVALID) throw UninitializedParameter(); |
1175 | 1174 |
Dijkstra<Digraph,LengthMap,TR> |
1176 | 1175 |
dij(*reinterpret_cast<const Digraph*>(Base::_g), |
1177 | 1176 |
*reinterpret_cast<const LengthMap*>(Base::_length)); |
1178 | 1177 |
if(Base::_processed) |
1179 | 1178 |
dij.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed)); |
1180 | 1179 |
if(Base::_pred) |
1181 | 1180 |
dij.predMap(*reinterpret_cast<PredMap*>(Base::_pred)); |
1182 | 1181 |
if(Base::_dist) |
1183 | 1182 |
dij.distMap(*reinterpret_cast<DistMap*>(Base::_dist)); |
1184 | 1183 |
dij.run(Base::_source); |
1185 | 1184 |
} |
1186 | 1185 |
|
1187 | 1186 |
///Runs Dijkstra algorithm from the given node. |
1188 | 1187 |
|
1189 | 1188 |
///Runs Dijkstra algorithm from the given node. |
1190 | 1189 |
///\param s is the given source. |
1191 | 1190 |
void run(Node s) |
1192 | 1191 |
{ |
1193 | 1192 |
Base::_source=s; |
1194 | 1193 |
run(); |
1195 | 1194 |
} |
1196 | 1195 |
|
1197 | 1196 |
/// Sets the source node, from which the Dijkstra algorithm runs. |
1198 | 1197 |
|
1199 | 1198 |
/// Sets the source node, from which the Dijkstra algorithm runs. |
1200 | 1199 |
/// \param s is the source node. |
1201 | 1200 |
DijkstraWizard<TR> &source(Node s) |
1202 | 1201 |
{ |
1203 | 1202 |
Base::_source=s; |
1204 | 1203 |
return *this; |
1205 | 1204 |
} |
1206 | 1205 |
|
1207 | 1206 |
template<class T> |
1208 |
struct |
|
1207 |
struct SetPredMapBase : public Base { |
|
1209 | 1208 |
typedef T PredMap; |
1210 | 1209 |
static PredMap *createPredMap(const Digraph &) { return 0; }; |
1211 |
|
|
1210 |
SetPredMapBase(const TR &b) : TR(b) {} |
|
1212 | 1211 |
}; |
1213 | 1212 |
///\brief \ref named-templ-param "Named parameter" |
1214 | 1213 |
///for setting \ref PredMap object. |
1215 | 1214 |
/// |
1216 | 1215 |
///\ref named-templ-param "Named parameter" |
1217 | 1216 |
///for setting \ref PredMap object. |
1218 | 1217 |
template<class T> |
1219 |
DijkstraWizard< |
|
1218 |
DijkstraWizard<SetPredMapBase<T> > predMap(const T &t) |
|
1220 | 1219 |
{ |
1221 | 1220 |
Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1222 |
return DijkstraWizard< |
|
1221 |
return DijkstraWizard<SetPredMapBase<T> >(*this); |
|
1223 | 1222 |
} |
1224 | 1223 |
|
1225 | 1224 |
template<class T> |
1226 |
struct |
|
1225 |
struct SetProcessedMapBase : public Base { |
|
1227 | 1226 |
typedef T ProcessedMap; |
1228 | 1227 |
static ProcessedMap *createProcessedMap(const Digraph &) { return 0; }; |
1229 |
|
|
1228 |
SetProcessedMapBase(const TR &b) : TR(b) {} |
|
1230 | 1229 |
}; |
1231 | 1230 |
///\brief \ref named-templ-param "Named parameter" |
1232 | 1231 |
///for setting \ref ProcessedMap object. |
1233 | 1232 |
/// |
1234 | 1233 |
/// \ref named-templ-param "Named parameter" |
1235 | 1234 |
///for setting \ref ProcessedMap object. |
1236 | 1235 |
template<class T> |
1237 |
DijkstraWizard< |
|
1236 |
DijkstraWizard<SetProcessedMapBase<T> > processedMap(const T &t) |
|
1238 | 1237 |
{ |
1239 | 1238 |
Base::_processed=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1240 |
return DijkstraWizard< |
|
1239 |
return DijkstraWizard<SetProcessedMapBase<T> >(*this); |
|
1241 | 1240 |
} |
1242 | 1241 |
|
1243 | 1242 |
template<class T> |
1244 |
struct |
|
1243 |
struct SetDistMapBase : public Base { |
|
1245 | 1244 |
typedef T DistMap; |
1246 | 1245 |
static DistMap *createDistMap(const Digraph &) { return 0; }; |
1247 |
|
|
1246 |
SetDistMapBase(const TR &b) : TR(b) {} |
|
1248 | 1247 |
}; |
1249 | 1248 |
///\brief \ref named-templ-param "Named parameter" |
1250 | 1249 |
///for setting \ref DistMap object. |
1251 | 1250 |
/// |
1252 | 1251 |
///\ref named-templ-param "Named parameter" |
1253 | 1252 |
///for setting \ref DistMap object. |
1254 | 1253 |
template<class T> |
1255 |
DijkstraWizard< |
|
1254 |
DijkstraWizard<SetDistMapBase<T> > distMap(const T &t) |
|
1256 | 1255 |
{ |
1257 | 1256 |
Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t)); |
1258 |
return DijkstraWizard< |
|
1257 |
return DijkstraWizard<SetDistMapBase<T> >(*this); |
|
1259 | 1258 |
} |
1260 | 1259 |
|
1261 | 1260 |
}; |
1262 | 1261 |
|
1263 | 1262 |
///Function type interface for Dijkstra algorithm. |
1264 | 1263 |
|
1265 | 1264 |
/// \ingroup shortest_path |
1266 | 1265 |
///Function type interface for Dijkstra algorithm. |
1267 | 1266 |
/// |
1268 | 1267 |
///This function also has several |
1269 | 1268 |
///\ref named-templ-func-param "named parameters", |
1270 | 1269 |
///they are declared as the members of class \ref DijkstraWizard. |
1271 | 1270 |
///The following |
1272 | 1271 |
///example shows how to use these parameters. |
1273 | 1272 |
///\code |
1274 | 1273 |
/// dijkstra(g,length,source).predMap(preds).run(); |
1275 | 1274 |
///\endcode |
1276 | 1275 |
///\warning Don't forget to put the \ref DijkstraWizard::run() "run()" |
1277 | 1276 |
///to the end of the parameter list. |
1278 | 1277 |
///\sa DijkstraWizard |
1279 | 1278 |
///\sa Dijkstra |
1280 | 1279 |
template<class GR, class LM> |
1281 | 1280 |
DijkstraWizard<DijkstraWizardBase<GR,LM> > |
1282 | 1281 |
dijkstra(const GR &g,const LM &l,typename GR::Node s=INVALID) |
1283 | 1282 |
{ |
1284 | 1283 |
return DijkstraWizard<DijkstraWizardBase<GR,LM> >(g,l,s); |
1285 | 1284 |
} |
1286 | 1285 |
|
1287 | 1286 |
} //END OF NAMESPACE LEMON |
1288 | 1287 |
|
1289 | 1288 |
#endif |
1 | 1 |
/* -*- mode: C++; indent-tabs-mode: nil; -*- |
2 | 2 |
* |
3 | 3 |
* This file is a part of LEMON, a generic C++ optimization library. |
4 | 4 |
* |
5 | 5 |
* Copyright (C) 2003-2008 |
6 | 6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
7 | 7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
8 | 8 |
* |
9 | 9 |
* Permission to use, modify and distribute this software is granted |
10 | 10 |
* provided that this copyright notice appears in all copies. For |
11 | 11 |
* precise terms see the accompanying LICENSE file. |
12 | 12 |
* |
13 | 13 |
* This software is provided "AS IS" with no warranty of any kind, |
14 | 14 |
* express or implied, and with no claim as to its suitability for any |
15 | 15 |
* purpose. |
16 | 16 |
* |
17 | 17 |
*/ |
18 | 18 |
|
19 | 19 |
#include <iostream> |
20 | 20 |
#include <fstream> |
21 | 21 |
#include <string> |
22 | 22 |
#include <vector> |
23 | 23 |
|
24 | 24 |
#include <lemon/concept_check.h> |
25 | 25 |
#include <lemon/concepts/heap.h> |
26 | 26 |
|
27 | 27 |
#include <lemon/smart_graph.h> |
28 | 28 |
|
29 | 29 |
#include <lemon/lgf_reader.h> |
30 | 30 |
#include <lemon/dijkstra.h> |
31 | 31 |
#include <lemon/maps.h> |
32 | 32 |
|
33 | 33 |
#include <lemon/bin_heap.h> |
34 | 34 |
|
35 | 35 |
#include "test_tools.h" |
36 | 36 |
|
37 | 37 |
using namespace lemon; |
38 | 38 |
using namespace lemon::concepts; |
39 | 39 |
|
40 | 40 |
typedef ListDigraph Digraph; |
41 | 41 |
DIGRAPH_TYPEDEFS(Digraph); |
42 | 42 |
|
43 | 43 |
char test_lgf[] = |
44 | 44 |
"@nodes\n" |
45 | 45 |
"label\n" |
46 | 46 |
"0\n" |
47 | 47 |
"1\n" |
48 | 48 |
"2\n" |
49 | 49 |
"3\n" |
50 | 50 |
"4\n" |
51 | 51 |
"5\n" |
52 | 52 |
"6\n" |
53 | 53 |
"7\n" |
54 | 54 |
"8\n" |
55 | 55 |
"9\n" |
56 | 56 |
"@arcs\n" |
57 | 57 |
" label capacity\n" |
58 | 58 |
"0 5 0 94\n" |
59 | 59 |
"3 9 1 11\n" |
60 | 60 |
"8 7 2 83\n" |
61 | 61 |
"1 2 3 94\n" |
62 | 62 |
"5 7 4 35\n" |
63 | 63 |
"7 4 5 84\n" |
64 | 64 |
"9 5 6 38\n" |
65 | 65 |
"0 4 7 96\n" |
66 | 66 |
"6 7 8 6\n" |
67 | 67 |
"3 1 9 27\n" |
68 | 68 |
"5 2 10 77\n" |
69 | 69 |
"5 6 11 69\n" |
70 | 70 |
"6 5 12 41\n" |
71 | 71 |
"4 6 13 70\n" |
72 | 72 |
"3 2 14 45\n" |
73 | 73 |
"7 9 15 93\n" |
74 | 74 |
"5 9 16 50\n" |
75 | 75 |
"9 0 17 94\n" |
76 | 76 |
"9 6 18 67\n" |
77 | 77 |
"0 9 19 86\n" |
78 | 78 |
"@attributes\n" |
79 | 79 |
"source 3\n"; |
80 | 80 |
|
81 | 81 |
int test_seq[] = { 2, 28, 19, 27, 33, 25, 13, 41, 10, 26, 1, 9, 4, 34}; |
82 | 82 |
int test_inc[] = {20, 28, 34, 16, 0, 46, 44, 0, 42, 32, 14, 8, 6, 37}; |
83 | 83 |
|
84 | 84 |
int test_len = sizeof(test_seq) / sizeof(test_seq[0]); |
85 | 85 |
|
86 | 86 |
template <typename Heap> |
87 | 87 |
void heapSortTest() { |
88 | 88 |
RangeMap<int> map(test_len, -1); |
89 | 89 |
|
90 | 90 |
Heap heap(map); |
91 | 91 |
|
92 | 92 |
std::vector<int> v(test_len); |
93 | 93 |
|
94 | 94 |
for (int i = 0; i < test_len; ++i) { |
95 | 95 |
v[i] = test_seq[i]; |
96 | 96 |
heap.push(i, v[i]); |
97 | 97 |
} |
98 | 98 |
std::sort(v.begin(), v.end()); |
99 | 99 |
for (int i = 0; i < test_len; ++i) { |
100 | 100 |
check(v[i] == heap.prio() ,"Wrong order in heap sort."); |
101 | 101 |
heap.pop(); |
102 | 102 |
} |
103 | 103 |
} |
104 | 104 |
|
105 | 105 |
template <typename Heap> |
106 | 106 |
void heapIncreaseTest() { |
107 | 107 |
RangeMap<int> map(test_len, -1); |
108 | 108 |
|
109 | 109 |
Heap heap(map); |
110 | 110 |
|
111 | 111 |
std::vector<int> v(test_len); |
112 | 112 |
|
113 | 113 |
for (int i = 0; i < test_len; ++i) { |
114 | 114 |
v[i] = test_seq[i]; |
115 | 115 |
heap.push(i, v[i]); |
116 | 116 |
} |
117 | 117 |
for (int i = 0; i < test_len; ++i) { |
118 | 118 |
v[i] += test_inc[i]; |
119 | 119 |
heap.increase(i, v[i]); |
120 | 120 |
} |
121 | 121 |
std::sort(v.begin(), v.end()); |
122 | 122 |
for (int i = 0; i < test_len; ++i) { |
123 | 123 |
check(v[i] == heap.prio() ,"Wrong order in heap increase test."); |
124 | 124 |
heap.pop(); |
125 | 125 |
} |
126 | 126 |
} |
127 | 127 |
|
128 | 128 |
|
129 | 129 |
|
130 | 130 |
template <typename Heap> |
131 | 131 |
void dijkstraHeapTest(const Digraph& digraph, const IntArcMap& length, |
132 | 132 |
Node source) { |
133 | 133 |
|
134 |
typename Dijkstra<Digraph, IntArcMap>::template |
|
134 |
typename Dijkstra<Digraph, IntArcMap>::template SetStandardHeap<Heap>:: |
|
135 | 135 |
Create dijkstra(digraph, length); |
136 | 136 |
|
137 | 137 |
dijkstra.run(source); |
138 | 138 |
|
139 | 139 |
for(ArcIt a(digraph); a != INVALID; ++a) { |
140 | 140 |
Node s = digraph.source(a); |
141 | 141 |
Node t = digraph.target(a); |
142 | 142 |
if (dijkstra.reached(s)) { |
143 | 143 |
check( dijkstra.dist(t) - dijkstra.dist(s) <= length[a], |
144 | 144 |
"Error in a shortest path tree!"); |
145 | 145 |
} |
146 | 146 |
} |
147 | 147 |
|
148 | 148 |
for(NodeIt n(digraph); n != INVALID; ++n) { |
149 | 149 |
if ( dijkstra.reached(n) && dijkstra.predArc(n) != INVALID ) { |
150 | 150 |
Arc a = dijkstra.predArc(n); |
151 | 151 |
Node s = digraph.source(a); |
152 | 152 |
check( dijkstra.dist(n) - dijkstra.dist(s) == length[a], |
153 | 153 |
"Error in a shortest path tree!"); |
154 | 154 |
} |
155 | 155 |
} |
156 | 156 |
|
157 | 157 |
} |
158 | 158 |
|
159 | 159 |
int main() { |
160 | 160 |
|
161 | 161 |
typedef int Item; |
162 | 162 |
typedef int Prio; |
163 | 163 |
typedef RangeMap<int> ItemIntMap; |
164 | 164 |
|
165 | 165 |
Digraph digraph; |
166 | 166 |
IntArcMap length(digraph); |
167 | 167 |
Node source; |
168 | 168 |
|
169 | 169 |
std::istringstream input(test_lgf); |
170 | 170 |
digraphReader(input, digraph). |
171 | 171 |
arcMap("capacity", length). |
172 | 172 |
node("source", source). |
173 | 173 |
run(); |
174 | 174 |
|
175 | 175 |
{ |
176 | 176 |
typedef BinHeap<Prio, ItemIntMap> IntHeap; |
177 | 177 |
checkConcept<Heap<Prio, ItemIntMap>, IntHeap>(); |
178 | 178 |
heapSortTest<IntHeap>(); |
179 | 179 |
heapIncreaseTest<IntHeap>(); |
180 | 180 |
|
181 | 181 |
typedef BinHeap<Prio, IntNodeMap > NodeHeap; |
182 | 182 |
checkConcept<Heap<Prio, IntNodeMap >, NodeHeap>(); |
183 | 183 |
dijkstraHeapTest<NodeHeap>(digraph, length, source); |
184 | 184 |
} |
185 | 185 |
|
186 | 186 |
return 0; |
187 | 187 |
} |
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