1 | /* -*- mode: C++; indent-tabs-mode: nil; -*- |
---|
2 | * |
---|
3 | * This file is a part of LEMON, a generic C++ optimization library. |
---|
4 | * |
---|
5 | * Copyright (C) 2003-2008 |
---|
6 | * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
---|
7 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
---|
8 | * |
---|
9 | * Permission to use, modify and distribute this software is granted |
---|
10 | * provided that this copyright notice appears in all copies. For |
---|
11 | * precise terms see the accompanying LICENSE file. |
---|
12 | * |
---|
13 | * This software is provided "AS IS" with no warranty of any kind, |
---|
14 | * express or implied, and with no claim as to its suitability for any |
---|
15 | * purpose. |
---|
16 | * |
---|
17 | */ |
---|
18 | |
---|
19 | #ifndef LEMON_SMART_GRAPH_H |
---|
20 | #define LEMON_SMART_GRAPH_H |
---|
21 | |
---|
22 | ///\ingroup graphs |
---|
23 | ///\file |
---|
24 | ///\brief SmartDigraph and SmartGraph classes. |
---|
25 | |
---|
26 | #include <vector> |
---|
27 | |
---|
28 | #include <lemon/core.h> |
---|
29 | #include <lemon/error.h> |
---|
30 | #include <lemon/bits/graph_extender.h> |
---|
31 | |
---|
32 | namespace lemon { |
---|
33 | |
---|
34 | class SmartDigraph; |
---|
35 | ///Base of SmartDigraph |
---|
36 | |
---|
37 | ///Base of SmartDigraph |
---|
38 | /// |
---|
39 | class SmartDigraphBase { |
---|
40 | protected: |
---|
41 | |
---|
42 | struct NodeT |
---|
43 | { |
---|
44 | int first_in, first_out; |
---|
45 | NodeT() {} |
---|
46 | }; |
---|
47 | struct ArcT |
---|
48 | { |
---|
49 | int target, source, next_in, next_out; |
---|
50 | ArcT() {} |
---|
51 | }; |
---|
52 | |
---|
53 | std::vector<NodeT> nodes; |
---|
54 | std::vector<ArcT> arcs; |
---|
55 | |
---|
56 | public: |
---|
57 | |
---|
58 | typedef SmartDigraphBase Graph; |
---|
59 | |
---|
60 | class Node; |
---|
61 | class Arc; |
---|
62 | |
---|
63 | public: |
---|
64 | |
---|
65 | SmartDigraphBase() : nodes(), arcs() { } |
---|
66 | SmartDigraphBase(const SmartDigraphBase &_g) |
---|
67 | : nodes(_g.nodes), arcs(_g.arcs) { } |
---|
68 | |
---|
69 | typedef True NodeNumTag; |
---|
70 | typedef True EdgeNumTag; |
---|
71 | |
---|
72 | int nodeNum() const { return nodes.size(); } |
---|
73 | int arcNum() const { return arcs.size(); } |
---|
74 | |
---|
75 | int maxNodeId() const { return nodes.size()-1; } |
---|
76 | int maxArcId() const { return arcs.size()-1; } |
---|
77 | |
---|
78 | Node addNode() { |
---|
79 | int n = nodes.size(); |
---|
80 | nodes.push_back(NodeT()); |
---|
81 | nodes[n].first_in = -1; |
---|
82 | nodes[n].first_out = -1; |
---|
83 | return Node(n); |
---|
84 | } |
---|
85 | |
---|
86 | Arc addArc(Node u, Node v) { |
---|
87 | int n = arcs.size(); |
---|
88 | arcs.push_back(ArcT()); |
---|
89 | arcs[n].source = u._id; |
---|
90 | arcs[n].target = v._id; |
---|
91 | arcs[n].next_out = nodes[u._id].first_out; |
---|
92 | arcs[n].next_in = nodes[v._id].first_in; |
---|
93 | nodes[u._id].first_out = nodes[v._id].first_in = n; |
---|
94 | |
---|
95 | return Arc(n); |
---|
96 | } |
---|
97 | |
---|
98 | void clear() { |
---|
99 | arcs.clear(); |
---|
100 | nodes.clear(); |
---|
101 | } |
---|
102 | |
---|
103 | Node source(Arc a) const { return Node(arcs[a._id].source); } |
---|
104 | Node target(Arc a) const { return Node(arcs[a._id].target); } |
---|
105 | |
---|
106 | static int id(Node v) { return v._id; } |
---|
107 | static int id(Arc a) { return a._id; } |
---|
108 | |
---|
109 | static Node nodeFromId(int id) { return Node(id);} |
---|
110 | static Arc arcFromId(int id) { return Arc(id);} |
---|
111 | |
---|
112 | bool valid(Node n) const { |
---|
113 | return n._id >= 0 && n._id < static_cast<int>(nodes.size()); |
---|
114 | } |
---|
115 | bool valid(Arc a) const { |
---|
116 | return a._id >= 0 && a._id < static_cast<int>(arcs.size()); |
---|
117 | } |
---|
118 | |
---|
119 | class Node { |
---|
120 | friend class SmartDigraphBase; |
---|
121 | friend class SmartDigraph; |
---|
122 | |
---|
123 | protected: |
---|
124 | int _id; |
---|
125 | explicit Node(int id) : _id(id) {} |
---|
126 | public: |
---|
127 | Node() {} |
---|
128 | Node (Invalid) : _id(-1) {} |
---|
129 | bool operator==(const Node i) const {return _id == i._id;} |
---|
130 | bool operator!=(const Node i) const {return _id != i._id;} |
---|
131 | bool operator<(const Node i) const {return _id < i._id;} |
---|
132 | }; |
---|
133 | |
---|
134 | |
---|
135 | class Arc { |
---|
136 | friend class SmartDigraphBase; |
---|
137 | friend class SmartDigraph; |
---|
138 | |
---|
139 | protected: |
---|
140 | int _id; |
---|
141 | explicit Arc(int id) : _id(id) {} |
---|
142 | public: |
---|
143 | Arc() { } |
---|
144 | Arc (Invalid) : _id(-1) {} |
---|
145 | bool operator==(const Arc i) const {return _id == i._id;} |
---|
146 | bool operator!=(const Arc i) const {return _id != i._id;} |
---|
147 | bool operator<(const Arc i) const {return _id < i._id;} |
---|
148 | }; |
---|
149 | |
---|
150 | void first(Node& node) const { |
---|
151 | node._id = nodes.size() - 1; |
---|
152 | } |
---|
153 | |
---|
154 | static void next(Node& node) { |
---|
155 | --node._id; |
---|
156 | } |
---|
157 | |
---|
158 | void first(Arc& arc) const { |
---|
159 | arc._id = arcs.size() - 1; |
---|
160 | } |
---|
161 | |
---|
162 | static void next(Arc& arc) { |
---|
163 | --arc._id; |
---|
164 | } |
---|
165 | |
---|
166 | void firstOut(Arc& arc, const Node& node) const { |
---|
167 | arc._id = nodes[node._id].first_out; |
---|
168 | } |
---|
169 | |
---|
170 | void nextOut(Arc& arc) const { |
---|
171 | arc._id = arcs[arc._id].next_out; |
---|
172 | } |
---|
173 | |
---|
174 | void firstIn(Arc& arc, const Node& node) const { |
---|
175 | arc._id = nodes[node._id].first_in; |
---|
176 | } |
---|
177 | |
---|
178 | void nextIn(Arc& arc) const { |
---|
179 | arc._id = arcs[arc._id].next_in; |
---|
180 | } |
---|
181 | |
---|
182 | }; |
---|
183 | |
---|
184 | typedef DigraphExtender<SmartDigraphBase> ExtendedSmartDigraphBase; |
---|
185 | |
---|
186 | ///\ingroup graphs |
---|
187 | /// |
---|
188 | ///\brief A smart directed graph class. |
---|
189 | /// |
---|
190 | ///This is a simple and fast digraph implementation. |
---|
191 | ///It is also quite memory efficient, but at the price |
---|
192 | ///that <b> it does support only limited (only stack-like) |
---|
193 | ///node and arc deletions</b>. |
---|
194 | ///It conforms to the \ref concepts::Digraph "Digraph concept" with |
---|
195 | ///an important extra feature that its maps are real \ref |
---|
196 | ///concepts::ReferenceMap "reference map"s. |
---|
197 | /// |
---|
198 | ///\sa concepts::Digraph. |
---|
199 | class SmartDigraph : public ExtendedSmartDigraphBase { |
---|
200 | public: |
---|
201 | |
---|
202 | typedef ExtendedSmartDigraphBase Parent; |
---|
203 | |
---|
204 | private: |
---|
205 | |
---|
206 | ///SmartDigraph is \e not copy constructible. Use DigraphCopy() instead. |
---|
207 | |
---|
208 | ///SmartDigraph is \e not copy constructible. Use DigraphCopy() instead. |
---|
209 | /// |
---|
210 | SmartDigraph(const SmartDigraph &) : ExtendedSmartDigraphBase() {}; |
---|
211 | ///\brief Assignment of SmartDigraph to another one is \e not allowed. |
---|
212 | ///Use DigraphCopy() instead. |
---|
213 | |
---|
214 | ///Assignment of SmartDigraph to another one is \e not allowed. |
---|
215 | ///Use DigraphCopy() instead. |
---|
216 | void operator=(const SmartDigraph &) {} |
---|
217 | |
---|
218 | public: |
---|
219 | |
---|
220 | /// Constructor |
---|
221 | |
---|
222 | /// Constructor. |
---|
223 | /// |
---|
224 | SmartDigraph() {}; |
---|
225 | |
---|
226 | ///Add a new node to the digraph. |
---|
227 | |
---|
228 | /// \return the new node. |
---|
229 | /// |
---|
230 | Node addNode() { return Parent::addNode(); } |
---|
231 | |
---|
232 | ///Add a new arc to the digraph. |
---|
233 | |
---|
234 | ///Add a new arc to the digraph with source node \c s |
---|
235 | ///and target node \c t. |
---|
236 | ///\return the new arc. |
---|
237 | Arc addArc(const Node& s, const Node& t) { |
---|
238 | return Parent::addArc(s, t); |
---|
239 | } |
---|
240 | |
---|
241 | /// \brief Using this it is possible to avoid the superfluous memory |
---|
242 | /// allocation. |
---|
243 | |
---|
244 | /// Using this it is possible to avoid the superfluous memory |
---|
245 | /// allocation: if you know that the digraph you want to build will |
---|
246 | /// be very large (e.g. it will contain millions of nodes and/or arcs) |
---|
247 | /// then it is worth reserving space for this amount before starting |
---|
248 | /// to build the digraph. |
---|
249 | /// \sa reserveArc |
---|
250 | void reserveNode(int n) { nodes.reserve(n); }; |
---|
251 | |
---|
252 | /// \brief Using this it is possible to avoid the superfluous memory |
---|
253 | /// allocation. |
---|
254 | |
---|
255 | /// Using this it is possible to avoid the superfluous memory |
---|
256 | /// allocation: if you know that the digraph you want to build will |
---|
257 | /// be very large (e.g. it will contain millions of nodes and/or arcs) |
---|
258 | /// then it is worth reserving space for this amount before starting |
---|
259 | /// to build the digraph. |
---|
260 | /// \sa reserveNode |
---|
261 | void reserveArc(int m) { arcs.reserve(m); }; |
---|
262 | |
---|
263 | /// \brief Node validity check |
---|
264 | /// |
---|
265 | /// This function gives back true if the given node is valid, |
---|
266 | /// ie. it is a real node of the graph. |
---|
267 | /// |
---|
268 | /// \warning A removed node (using Snapshot) could become valid again |
---|
269 | /// when new nodes are added to the graph. |
---|
270 | bool valid(Node n) const { return Parent::valid(n); } |
---|
271 | |
---|
272 | /// \brief Arc validity check |
---|
273 | /// |
---|
274 | /// This function gives back true if the given arc is valid, |
---|
275 | /// ie. it is a real arc of the graph. |
---|
276 | /// |
---|
277 | /// \warning A removed arc (using Snapshot) could become valid again |
---|
278 | /// when new arcs are added to the graph. |
---|
279 | bool valid(Arc a) const { return Parent::valid(a); } |
---|
280 | |
---|
281 | ///Clear the digraph. |
---|
282 | |
---|
283 | ///Erase all the nodes and arcs from the digraph. |
---|
284 | /// |
---|
285 | void clear() { |
---|
286 | Parent::clear(); |
---|
287 | } |
---|
288 | |
---|
289 | ///Split a node. |
---|
290 | |
---|
291 | ///This function splits a node. First a new node is added to the digraph, |
---|
292 | ///then the source of each outgoing arc of \c n is moved to this new node. |
---|
293 | ///If \c connect is \c true (this is the default value), then a new arc |
---|
294 | ///from \c n to the newly created node is also added. |
---|
295 | ///\return The newly created node. |
---|
296 | /// |
---|
297 | ///\note The <tt>Arc</tt>s |
---|
298 | ///referencing a moved arc remain |
---|
299 | ///valid. However <tt>InArc</tt>'s and <tt>OutArc</tt>'s |
---|
300 | ///may be invalidated. |
---|
301 | ///\warning This functionality cannot be used together with the Snapshot |
---|
302 | ///feature. |
---|
303 | Node split(Node n, bool connect = true) |
---|
304 | { |
---|
305 | Node b = addNode(); |
---|
306 | nodes[b._id].first_out=nodes[n._id].first_out; |
---|
307 | nodes[n._id].first_out=-1; |
---|
308 | for(int i=nodes[b._id].first_out;i!=-1;i++) arcs[i].source=b._id; |
---|
309 | if(connect) addArc(n,b); |
---|
310 | return b; |
---|
311 | } |
---|
312 | |
---|
313 | public: |
---|
314 | |
---|
315 | class Snapshot; |
---|
316 | |
---|
317 | protected: |
---|
318 | |
---|
319 | void restoreSnapshot(const Snapshot &s) |
---|
320 | { |
---|
321 | while(s.arc_num<arcs.size()) { |
---|
322 | Arc arc = arcFromId(arcs.size()-1); |
---|
323 | Parent::notifier(Arc()).erase(arc); |
---|
324 | nodes[arcs.back().source].first_out=arcs.back().next_out; |
---|
325 | nodes[arcs.back().target].first_in=arcs.back().next_in; |
---|
326 | arcs.pop_back(); |
---|
327 | } |
---|
328 | while(s.node_num<nodes.size()) { |
---|
329 | Node node = nodeFromId(nodes.size()-1); |
---|
330 | Parent::notifier(Node()).erase(node); |
---|
331 | nodes.pop_back(); |
---|
332 | } |
---|
333 | } |
---|
334 | |
---|
335 | public: |
---|
336 | |
---|
337 | ///Class to make a snapshot of the digraph and to restrore to it later. |
---|
338 | |
---|
339 | ///Class to make a snapshot of the digraph and to restrore to it later. |
---|
340 | /// |
---|
341 | ///The newly added nodes and arcs can be removed using the |
---|
342 | ///restore() function. |
---|
343 | ///\note After you restore a state, you cannot restore |
---|
344 | ///a later state, in other word you cannot add again the arcs deleted |
---|
345 | ///by restore() using another one Snapshot instance. |
---|
346 | /// |
---|
347 | ///\warning If you do not use correctly the snapshot that can cause |
---|
348 | ///either broken program, invalid state of the digraph, valid but |
---|
349 | ///not the restored digraph or no change. Because the runtime performance |
---|
350 | ///the validity of the snapshot is not stored. |
---|
351 | class Snapshot |
---|
352 | { |
---|
353 | SmartDigraph *_graph; |
---|
354 | protected: |
---|
355 | friend class SmartDigraph; |
---|
356 | unsigned int node_num; |
---|
357 | unsigned int arc_num; |
---|
358 | public: |
---|
359 | ///Default constructor. |
---|
360 | |
---|
361 | ///Default constructor. |
---|
362 | ///To actually make a snapshot you must call save(). |
---|
363 | /// |
---|
364 | Snapshot() : _graph(0) {} |
---|
365 | ///Constructor that immediately makes a snapshot |
---|
366 | |
---|
367 | ///This constructor immediately makes a snapshot of the digraph. |
---|
368 | ///\param _g The digraph we make a snapshot of. |
---|
369 | Snapshot(SmartDigraph &graph) : _graph(&graph) { |
---|
370 | node_num=_graph->nodes.size(); |
---|
371 | arc_num=_graph->arcs.size(); |
---|
372 | } |
---|
373 | |
---|
374 | ///Make a snapshot. |
---|
375 | |
---|
376 | ///Make a snapshot of the digraph. |
---|
377 | /// |
---|
378 | ///This function can be called more than once. In case of a repeated |
---|
379 | ///call, the previous snapshot gets lost. |
---|
380 | ///\param _g The digraph we make the snapshot of. |
---|
381 | void save(SmartDigraph &graph) |
---|
382 | { |
---|
383 | _graph=&graph; |
---|
384 | node_num=_graph->nodes.size(); |
---|
385 | arc_num=_graph->arcs.size(); |
---|
386 | } |
---|
387 | |
---|
388 | ///Undo the changes until a snapshot. |
---|
389 | |
---|
390 | ///Undo the changes until a snapshot created by save(). |
---|
391 | /// |
---|
392 | ///\note After you restored a state, you cannot restore |
---|
393 | ///a later state, in other word you cannot add again the arcs deleted |
---|
394 | ///by restore(). |
---|
395 | void restore() |
---|
396 | { |
---|
397 | _graph->restoreSnapshot(*this); |
---|
398 | } |
---|
399 | }; |
---|
400 | }; |
---|
401 | |
---|
402 | |
---|
403 | class SmartGraphBase { |
---|
404 | |
---|
405 | protected: |
---|
406 | |
---|
407 | struct NodeT { |
---|
408 | int first_out; |
---|
409 | }; |
---|
410 | |
---|
411 | struct ArcT { |
---|
412 | int target; |
---|
413 | int next_out; |
---|
414 | }; |
---|
415 | |
---|
416 | std::vector<NodeT> nodes; |
---|
417 | std::vector<ArcT> arcs; |
---|
418 | |
---|
419 | int first_free_arc; |
---|
420 | |
---|
421 | public: |
---|
422 | |
---|
423 | typedef SmartGraphBase Digraph; |
---|
424 | |
---|
425 | class Node; |
---|
426 | class Arc; |
---|
427 | class Edge; |
---|
428 | |
---|
429 | class Node { |
---|
430 | friend class SmartGraphBase; |
---|
431 | protected: |
---|
432 | |
---|
433 | int _id; |
---|
434 | explicit Node(int id) { _id = id;} |
---|
435 | |
---|
436 | public: |
---|
437 | Node() {} |
---|
438 | Node (Invalid) { _id = -1; } |
---|
439 | bool operator==(const Node& node) const {return _id == node._id;} |
---|
440 | bool operator!=(const Node& node) const {return _id != node._id;} |
---|
441 | bool operator<(const Node& node) const {return _id < node._id;} |
---|
442 | }; |
---|
443 | |
---|
444 | class Edge { |
---|
445 | friend class SmartGraphBase; |
---|
446 | protected: |
---|
447 | |
---|
448 | int _id; |
---|
449 | explicit Edge(int id) { _id = id;} |
---|
450 | |
---|
451 | public: |
---|
452 | Edge() {} |
---|
453 | Edge (Invalid) { _id = -1; } |
---|
454 | bool operator==(const Edge& arc) const {return _id == arc._id;} |
---|
455 | bool operator!=(const Edge& arc) const {return _id != arc._id;} |
---|
456 | bool operator<(const Edge& arc) const {return _id < arc._id;} |
---|
457 | }; |
---|
458 | |
---|
459 | class Arc { |
---|
460 | friend class SmartGraphBase; |
---|
461 | protected: |
---|
462 | |
---|
463 | int _id; |
---|
464 | explicit Arc(int id) { _id = id;} |
---|
465 | |
---|
466 | public: |
---|
467 | operator Edge() const { |
---|
468 | return _id != -1 ? edgeFromId(_id / 2) : INVALID; |
---|
469 | } |
---|
470 | |
---|
471 | Arc() {} |
---|
472 | Arc (Invalid) { _id = -1; } |
---|
473 | bool operator==(const Arc& arc) const {return _id == arc._id;} |
---|
474 | bool operator!=(const Arc& arc) const {return _id != arc._id;} |
---|
475 | bool operator<(const Arc& arc) const {return _id < arc._id;} |
---|
476 | }; |
---|
477 | |
---|
478 | |
---|
479 | |
---|
480 | SmartGraphBase() |
---|
481 | : nodes(), arcs() {} |
---|
482 | |
---|
483 | |
---|
484 | int maxNodeId() const { return nodes.size()-1; } |
---|
485 | int maxEdgeId() const { return arcs.size() / 2 - 1; } |
---|
486 | int maxArcId() const { return arcs.size()-1; } |
---|
487 | |
---|
488 | Node source(Arc e) const { return Node(arcs[e._id ^ 1].target); } |
---|
489 | Node target(Arc e) const { return Node(arcs[e._id].target); } |
---|
490 | |
---|
491 | Node u(Edge e) const { return Node(arcs[2 * e._id].target); } |
---|
492 | Node v(Edge e) const { return Node(arcs[2 * e._id + 1].target); } |
---|
493 | |
---|
494 | static bool direction(Arc e) { |
---|
495 | return (e._id & 1) == 1; |
---|
496 | } |
---|
497 | |
---|
498 | static Arc direct(Edge e, bool d) { |
---|
499 | return Arc(e._id * 2 + (d ? 1 : 0)); |
---|
500 | } |
---|
501 | |
---|
502 | void first(Node& node) const { |
---|
503 | node._id = nodes.size() - 1; |
---|
504 | } |
---|
505 | |
---|
506 | void next(Node& node) const { |
---|
507 | --node._id; |
---|
508 | } |
---|
509 | |
---|
510 | void first(Arc& arc) const { |
---|
511 | arc._id = arcs.size() - 1; |
---|
512 | } |
---|
513 | |
---|
514 | void next(Arc& arc) const { |
---|
515 | --arc._id; |
---|
516 | } |
---|
517 | |
---|
518 | void first(Edge& arc) const { |
---|
519 | arc._id = arcs.size() / 2 - 1; |
---|
520 | } |
---|
521 | |
---|
522 | void next(Edge& arc) const { |
---|
523 | --arc._id; |
---|
524 | } |
---|
525 | |
---|
526 | void firstOut(Arc &arc, const Node& v) const { |
---|
527 | arc._id = nodes[v._id].first_out; |
---|
528 | } |
---|
529 | void nextOut(Arc &arc) const { |
---|
530 | arc._id = arcs[arc._id].next_out; |
---|
531 | } |
---|
532 | |
---|
533 | void firstIn(Arc &arc, const Node& v) const { |
---|
534 | arc._id = ((nodes[v._id].first_out) ^ 1); |
---|
535 | if (arc._id == -2) arc._id = -1; |
---|
536 | } |
---|
537 | void nextIn(Arc &arc) const { |
---|
538 | arc._id = ((arcs[arc._id ^ 1].next_out) ^ 1); |
---|
539 | if (arc._id == -2) arc._id = -1; |
---|
540 | } |
---|
541 | |
---|
542 | void firstInc(Edge &arc, bool& d, const Node& v) const { |
---|
543 | int de = nodes[v._id].first_out; |
---|
544 | if (de != -1) { |
---|
545 | arc._id = de / 2; |
---|
546 | d = ((de & 1) == 1); |
---|
547 | } else { |
---|
548 | arc._id = -1; |
---|
549 | d = true; |
---|
550 | } |
---|
551 | } |
---|
552 | void nextInc(Edge &arc, bool& d) const { |
---|
553 | int de = (arcs[(arc._id * 2) | (d ? 1 : 0)].next_out); |
---|
554 | if (de != -1) { |
---|
555 | arc._id = de / 2; |
---|
556 | d = ((de & 1) == 1); |
---|
557 | } else { |
---|
558 | arc._id = -1; |
---|
559 | d = true; |
---|
560 | } |
---|
561 | } |
---|
562 | |
---|
563 | static int id(Node v) { return v._id; } |
---|
564 | static int id(Arc e) { return e._id; } |
---|
565 | static int id(Edge e) { return e._id; } |
---|
566 | |
---|
567 | static Node nodeFromId(int id) { return Node(id);} |
---|
568 | static Arc arcFromId(int id) { return Arc(id);} |
---|
569 | static Edge edgeFromId(int id) { return Edge(id);} |
---|
570 | |
---|
571 | bool valid(Node n) const { |
---|
572 | return n._id >= 0 && n._id < static_cast<int>(nodes.size()); |
---|
573 | } |
---|
574 | bool valid(Arc a) const { |
---|
575 | return a._id >= 0 && a._id < static_cast<int>(arcs.size()); |
---|
576 | } |
---|
577 | bool valid(Edge e) const { |
---|
578 | return e._id >= 0 && 2 * e._id < static_cast<int>(arcs.size()); |
---|
579 | } |
---|
580 | |
---|
581 | Node addNode() { |
---|
582 | int n = nodes.size(); |
---|
583 | nodes.push_back(NodeT()); |
---|
584 | nodes[n].first_out = -1; |
---|
585 | |
---|
586 | return Node(n); |
---|
587 | } |
---|
588 | |
---|
589 | Edge addEdge(Node u, Node v) { |
---|
590 | int n = arcs.size(); |
---|
591 | arcs.push_back(ArcT()); |
---|
592 | arcs.push_back(ArcT()); |
---|
593 | |
---|
594 | arcs[n].target = u._id; |
---|
595 | arcs[n | 1].target = v._id; |
---|
596 | |
---|
597 | arcs[n].next_out = nodes[v._id].first_out; |
---|
598 | nodes[v._id].first_out = n; |
---|
599 | |
---|
600 | arcs[n | 1].next_out = nodes[u._id].first_out; |
---|
601 | nodes[u._id].first_out = (n | 1); |
---|
602 | |
---|
603 | return Edge(n / 2); |
---|
604 | } |
---|
605 | |
---|
606 | void clear() { |
---|
607 | arcs.clear(); |
---|
608 | nodes.clear(); |
---|
609 | } |
---|
610 | |
---|
611 | }; |
---|
612 | |
---|
613 | typedef GraphExtender<SmartGraphBase> ExtendedSmartGraphBase; |
---|
614 | |
---|
615 | /// \ingroup graphs |
---|
616 | /// |
---|
617 | /// \brief A smart undirected graph class. |
---|
618 | /// |
---|
619 | /// This is a simple and fast graph implementation. |
---|
620 | /// It is also quite memory efficient, but at the price |
---|
621 | /// that <b> it does support only limited (only stack-like) |
---|
622 | /// node and arc deletions</b>. |
---|
623 | /// Except from this it conforms to |
---|
624 | /// the \ref concepts::Graph "Graph concept". |
---|
625 | /// |
---|
626 | /// It also has an |
---|
627 | /// important extra feature that |
---|
628 | /// its maps are real \ref concepts::ReferenceMap "reference map"s. |
---|
629 | /// |
---|
630 | /// \sa concepts::Graph. |
---|
631 | /// |
---|
632 | class SmartGraph : public ExtendedSmartGraphBase { |
---|
633 | private: |
---|
634 | |
---|
635 | ///SmartGraph is \e not copy constructible. Use GraphCopy() instead. |
---|
636 | |
---|
637 | ///SmartGraph is \e not copy constructible. Use GraphCopy() instead. |
---|
638 | /// |
---|
639 | SmartGraph(const SmartGraph &) : ExtendedSmartGraphBase() {}; |
---|
640 | |
---|
641 | ///\brief Assignment of SmartGraph to another one is \e not allowed. |
---|
642 | ///Use GraphCopy() instead. |
---|
643 | |
---|
644 | ///Assignment of SmartGraph to another one is \e not allowed. |
---|
645 | ///Use GraphCopy() instead. |
---|
646 | void operator=(const SmartGraph &) {} |
---|
647 | |
---|
648 | public: |
---|
649 | |
---|
650 | typedef ExtendedSmartGraphBase Parent; |
---|
651 | |
---|
652 | /// Constructor |
---|
653 | |
---|
654 | /// Constructor. |
---|
655 | /// |
---|
656 | SmartGraph() {} |
---|
657 | |
---|
658 | ///Add a new node to the graph. |
---|
659 | |
---|
660 | /// \return the new node. |
---|
661 | /// |
---|
662 | Node addNode() { return Parent::addNode(); } |
---|
663 | |
---|
664 | ///Add a new edge to the graph. |
---|
665 | |
---|
666 | ///Add a new edge to the graph with node \c s |
---|
667 | ///and \c t. |
---|
668 | ///\return the new edge. |
---|
669 | Edge addEdge(const Node& s, const Node& t) { |
---|
670 | return Parent::addEdge(s, t); |
---|
671 | } |
---|
672 | |
---|
673 | /// \brief Node validity check |
---|
674 | /// |
---|
675 | /// This function gives back true if the given node is valid, |
---|
676 | /// ie. it is a real node of the graph. |
---|
677 | /// |
---|
678 | /// \warning A removed node (using Snapshot) could become valid again |
---|
679 | /// when new nodes are added to the graph. |
---|
680 | bool valid(Node n) const { return Parent::valid(n); } |
---|
681 | |
---|
682 | /// \brief Arc validity check |
---|
683 | /// |
---|
684 | /// This function gives back true if the given arc is valid, |
---|
685 | /// ie. it is a real arc of the graph. |
---|
686 | /// |
---|
687 | /// \warning A removed arc (using Snapshot) could become valid again |
---|
688 | /// when new edges are added to the graph. |
---|
689 | bool valid(Arc a) const { return Parent::valid(a); } |
---|
690 | |
---|
691 | /// \brief Edge validity check |
---|
692 | /// |
---|
693 | /// This function gives back true if the given edge is valid, |
---|
694 | /// ie. it is a real edge of the graph. |
---|
695 | /// |
---|
696 | /// \warning A removed edge (using Snapshot) could become valid again |
---|
697 | /// when new edges are added to the graph. |
---|
698 | bool valid(Edge e) const { return Parent::valid(e); } |
---|
699 | |
---|
700 | ///Clear the graph. |
---|
701 | |
---|
702 | ///Erase all the nodes and edges from the graph. |
---|
703 | /// |
---|
704 | void clear() { |
---|
705 | Parent::clear(); |
---|
706 | } |
---|
707 | |
---|
708 | public: |
---|
709 | |
---|
710 | class Snapshot; |
---|
711 | |
---|
712 | protected: |
---|
713 | |
---|
714 | void saveSnapshot(Snapshot &s) |
---|
715 | { |
---|
716 | s._graph = this; |
---|
717 | s.node_num = nodes.size(); |
---|
718 | s.arc_num = arcs.size(); |
---|
719 | } |
---|
720 | |
---|
721 | void restoreSnapshot(const Snapshot &s) |
---|
722 | { |
---|
723 | while(s.arc_num<arcs.size()) { |
---|
724 | int n=arcs.size()-1; |
---|
725 | Edge arc=edgeFromId(n/2); |
---|
726 | Parent::notifier(Edge()).erase(arc); |
---|
727 | std::vector<Arc> dir; |
---|
728 | dir.push_back(arcFromId(n)); |
---|
729 | dir.push_back(arcFromId(n-1)); |
---|
730 | Parent::notifier(Arc()).erase(dir); |
---|
731 | nodes[arcs[n].target].first_out=arcs[n].next_out; |
---|
732 | nodes[arcs[n-1].target].first_out=arcs[n-1].next_out; |
---|
733 | arcs.pop_back(); |
---|
734 | arcs.pop_back(); |
---|
735 | } |
---|
736 | while(s.node_num<nodes.size()) { |
---|
737 | int n=nodes.size()-1; |
---|
738 | Node node = nodeFromId(n); |
---|
739 | Parent::notifier(Node()).erase(node); |
---|
740 | nodes.pop_back(); |
---|
741 | } |
---|
742 | } |
---|
743 | |
---|
744 | public: |
---|
745 | |
---|
746 | ///Class to make a snapshot of the digraph and to restrore to it later. |
---|
747 | |
---|
748 | ///Class to make a snapshot of the digraph and to restrore to it later. |
---|
749 | /// |
---|
750 | ///The newly added nodes and arcs can be removed using the |
---|
751 | ///restore() function. |
---|
752 | /// |
---|
753 | ///\note After you restore a state, you cannot restore |
---|
754 | ///a later state, in other word you cannot add again the arcs deleted |
---|
755 | ///by restore() using another one Snapshot instance. |
---|
756 | /// |
---|
757 | ///\warning If you do not use correctly the snapshot that can cause |
---|
758 | ///either broken program, invalid state of the digraph, valid but |
---|
759 | ///not the restored digraph or no change. Because the runtime performance |
---|
760 | ///the validity of the snapshot is not stored. |
---|
761 | class Snapshot |
---|
762 | { |
---|
763 | SmartGraph *_graph; |
---|
764 | protected: |
---|
765 | friend class SmartGraph; |
---|
766 | unsigned int node_num; |
---|
767 | unsigned int arc_num; |
---|
768 | public: |
---|
769 | ///Default constructor. |
---|
770 | |
---|
771 | ///Default constructor. |
---|
772 | ///To actually make a snapshot you must call save(). |
---|
773 | /// |
---|
774 | Snapshot() : _graph(0) {} |
---|
775 | ///Constructor that immediately makes a snapshot |
---|
776 | |
---|
777 | ///This constructor immediately makes a snapshot of the digraph. |
---|
778 | ///\param g The digraph we make a snapshot of. |
---|
779 | Snapshot(SmartGraph &graph) { |
---|
780 | graph.saveSnapshot(*this); |
---|
781 | } |
---|
782 | |
---|
783 | ///Make a snapshot. |
---|
784 | |
---|
785 | ///Make a snapshot of the graph. |
---|
786 | /// |
---|
787 | ///This function can be called more than once. In case of a repeated |
---|
788 | ///call, the previous snapshot gets lost. |
---|
789 | ///\param g The digraph we make the snapshot of. |
---|
790 | void save(SmartGraph &graph) |
---|
791 | { |
---|
792 | graph.saveSnapshot(*this); |
---|
793 | } |
---|
794 | |
---|
795 | ///Undo the changes until a snapshot. |
---|
796 | |
---|
797 | ///Undo the changes until a snapshot created by save(). |
---|
798 | /// |
---|
799 | ///\note After you restored a state, you cannot restore |
---|
800 | ///a later state, in other word you cannot add again the arcs deleted |
---|
801 | ///by restore(). |
---|
802 | void restore() |
---|
803 | { |
---|
804 | _graph->restoreSnapshot(*this); |
---|
805 | } |
---|
806 | }; |
---|
807 | }; |
---|
808 | |
---|
809 | } //namespace lemon |
---|
810 | |
---|
811 | |
---|
812 | #endif //LEMON_SMART_GRAPH_H |
---|