1 | /* -*- C++ -*- |
---|
2 | * lemon/list_graph.h - Part of LEMON, a generic C++ optimization library |
---|
3 | * |
---|
4 | * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
---|
5 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
---|
6 | * |
---|
7 | * Permission to use, modify and distribute this software is granted |
---|
8 | * provided that this copyright notice appears in all copies. For |
---|
9 | * precise terms see the accompanying LICENSE file. |
---|
10 | * |
---|
11 | * This software is provided "AS IS" with no warranty of any kind, |
---|
12 | * express or implied, and with no claim as to its suitability for any |
---|
13 | * purpose. |
---|
14 | * |
---|
15 | */ |
---|
16 | |
---|
17 | #ifndef LEMON_LIST_GRAPH_H |
---|
18 | #define LEMON_LIST_GRAPH_H |
---|
19 | |
---|
20 | ///\ingroup graphs |
---|
21 | ///\file |
---|
22 | ///\brief ListGraph, SymListGraph classes. |
---|
23 | |
---|
24 | #include <lemon/bits/erasable_graph_extender.h> |
---|
25 | #include <lemon/bits/clearable_graph_extender.h> |
---|
26 | #include <lemon/bits/extendable_graph_extender.h> |
---|
27 | #include <lemon/bits/iterable_graph_extender.h> |
---|
28 | #include <lemon/bits/alteration_notifier.h> |
---|
29 | #include <lemon/bits/default_map.h> |
---|
30 | |
---|
31 | #include <lemon/bits/undir_graph_extender.h> |
---|
32 | |
---|
33 | #include <list> |
---|
34 | |
---|
35 | namespace lemon { |
---|
36 | |
---|
37 | class ListGraphBase { |
---|
38 | |
---|
39 | protected: |
---|
40 | struct NodeT { |
---|
41 | int first_in,first_out; |
---|
42 | int prev, next; |
---|
43 | }; |
---|
44 | |
---|
45 | struct EdgeT { |
---|
46 | int target, source; |
---|
47 | int prev_in, prev_out; |
---|
48 | int next_in, next_out; |
---|
49 | }; |
---|
50 | |
---|
51 | std::vector<NodeT> nodes; |
---|
52 | |
---|
53 | int first_node; |
---|
54 | |
---|
55 | int first_free_node; |
---|
56 | |
---|
57 | std::vector<EdgeT> edges; |
---|
58 | |
---|
59 | int first_free_edge; |
---|
60 | |
---|
61 | public: |
---|
62 | |
---|
63 | typedef ListGraphBase Graph; |
---|
64 | |
---|
65 | class Node { |
---|
66 | friend class ListGraphBase; |
---|
67 | protected: |
---|
68 | |
---|
69 | int id; |
---|
70 | Node(int pid) { id = pid;} |
---|
71 | |
---|
72 | public: |
---|
73 | Node() {} |
---|
74 | Node (Invalid) { id = -1; } |
---|
75 | bool operator==(const Node& node) const {return id == node.id;} |
---|
76 | bool operator!=(const Node& node) const {return id != node.id;} |
---|
77 | bool operator<(const Node& node) const {return id < node.id;} |
---|
78 | }; |
---|
79 | |
---|
80 | class Edge { |
---|
81 | friend class ListGraphBase; |
---|
82 | protected: |
---|
83 | |
---|
84 | int id; |
---|
85 | Edge(int pid) { id = pid;} |
---|
86 | |
---|
87 | public: |
---|
88 | Edge() {} |
---|
89 | Edge (Invalid) { id = -1; } |
---|
90 | bool operator==(const Edge& edge) const {return id == edge.id;} |
---|
91 | bool operator!=(const Edge& edge) const {return id != edge.id;} |
---|
92 | bool operator<(const Edge& edge) const {return id < edge.id;} |
---|
93 | }; |
---|
94 | |
---|
95 | |
---|
96 | |
---|
97 | ListGraphBase() |
---|
98 | : nodes(), first_node(-1), |
---|
99 | first_free_node(-1), edges(), first_free_edge(-1) {} |
---|
100 | |
---|
101 | |
---|
102 | /// Maximum node ID. |
---|
103 | |
---|
104 | /// Maximum node ID. |
---|
105 | ///\sa id(Node) |
---|
106 | int maxId(Node = INVALID) const { return nodes.size()-1; } |
---|
107 | |
---|
108 | /// Maximum edge ID. |
---|
109 | |
---|
110 | /// Maximum edge ID. |
---|
111 | ///\sa id(Edge) |
---|
112 | int maxId(Edge = INVALID) const { return edges.size()-1; } |
---|
113 | |
---|
114 | Node source(Edge e) const { return edges[e.id].source; } |
---|
115 | Node target(Edge e) const { return edges[e.id].target; } |
---|
116 | |
---|
117 | |
---|
118 | void first(Node& node) const { |
---|
119 | node.id = first_node; |
---|
120 | } |
---|
121 | |
---|
122 | void next(Node& node) const { |
---|
123 | node.id = nodes[node.id].next; |
---|
124 | } |
---|
125 | |
---|
126 | |
---|
127 | void first(Edge& e) const { |
---|
128 | int n; |
---|
129 | for(n = first_node; |
---|
130 | n!=-1 && nodes[n].first_in == -1; |
---|
131 | n = nodes[n].next); |
---|
132 | e.id = (n == -1) ? -1 : nodes[n].first_in; |
---|
133 | } |
---|
134 | |
---|
135 | void next(Edge& edge) const { |
---|
136 | if (edges[edge.id].next_in != -1) { |
---|
137 | edge.id = edges[edge.id].next_in; |
---|
138 | } else { |
---|
139 | int n; |
---|
140 | for(n = nodes[edges[edge.id].target].next; |
---|
141 | n!=-1 && nodes[n].first_in == -1; |
---|
142 | n = nodes[n].next); |
---|
143 | edge.id = (n == -1) ? -1 : nodes[n].first_in; |
---|
144 | } |
---|
145 | } |
---|
146 | |
---|
147 | void firstOut(Edge &e, const Node& v) const { |
---|
148 | e.id = nodes[v.id].first_out; |
---|
149 | } |
---|
150 | void nextOut(Edge &e) const { |
---|
151 | e.id=edges[e.id].next_out; |
---|
152 | } |
---|
153 | |
---|
154 | void firstIn(Edge &e, const Node& v) const { |
---|
155 | e.id = nodes[v.id].first_in; |
---|
156 | } |
---|
157 | void nextIn(Edge &e) const { |
---|
158 | e.id=edges[e.id].next_in; |
---|
159 | } |
---|
160 | |
---|
161 | |
---|
162 | static int id(Node v) { return v.id; } |
---|
163 | static int id(Edge e) { return e.id; } |
---|
164 | |
---|
165 | static Node fromId(int id, Node) { return Node(id);} |
---|
166 | static Edge fromId(int id, Edge) { return Edge(id);} |
---|
167 | |
---|
168 | /// Adds a new node to the graph. |
---|
169 | |
---|
170 | /// \warning It adds the new node to the front of the list. |
---|
171 | /// (i.e. the lastly added node becomes the first.) |
---|
172 | Node addNode() { |
---|
173 | int n; |
---|
174 | |
---|
175 | if(first_free_node==-1) { |
---|
176 | n = nodes.size(); |
---|
177 | nodes.push_back(NodeT()); |
---|
178 | } else { |
---|
179 | n = first_free_node; |
---|
180 | first_free_node = nodes[n].next; |
---|
181 | } |
---|
182 | |
---|
183 | nodes[n].next = first_node; |
---|
184 | if(first_node != -1) nodes[first_node].prev = n; |
---|
185 | first_node = n; |
---|
186 | nodes[n].prev = -1; |
---|
187 | |
---|
188 | nodes[n].first_in = nodes[n].first_out = -1; |
---|
189 | |
---|
190 | return Node(n); |
---|
191 | } |
---|
192 | |
---|
193 | Edge addEdge(Node u, Node v) { |
---|
194 | int n; |
---|
195 | |
---|
196 | if (first_free_edge == -1) { |
---|
197 | n = edges.size(); |
---|
198 | edges.push_back(EdgeT()); |
---|
199 | } else { |
---|
200 | n = first_free_edge; |
---|
201 | first_free_edge = edges[n].next_in; |
---|
202 | } |
---|
203 | |
---|
204 | edges[n].source = u.id; |
---|
205 | edges[n].target = v.id; |
---|
206 | |
---|
207 | edges[n].next_out = nodes[u.id].first_out; |
---|
208 | if(nodes[u.id].first_out != -1) { |
---|
209 | edges[nodes[u.id].first_out].prev_out = n; |
---|
210 | } |
---|
211 | |
---|
212 | edges[n].next_in = nodes[v.id].first_in; |
---|
213 | if(nodes[v.id].first_in != -1) { |
---|
214 | edges[nodes[v.id].first_in].prev_in = n; |
---|
215 | } |
---|
216 | |
---|
217 | edges[n].prev_in = edges[n].prev_out = -1; |
---|
218 | |
---|
219 | nodes[u.id].first_out = nodes[v.id].first_in = n; |
---|
220 | |
---|
221 | return Edge(n); |
---|
222 | } |
---|
223 | |
---|
224 | void erase(const Node& node) { |
---|
225 | int n = node.id; |
---|
226 | |
---|
227 | if(nodes[n].next != -1) { |
---|
228 | nodes[nodes[n].next].prev = nodes[n].prev; |
---|
229 | } |
---|
230 | |
---|
231 | if(nodes[n].prev != -1) { |
---|
232 | nodes[nodes[n].prev].next = nodes[n].next; |
---|
233 | } else { |
---|
234 | first_node = nodes[n].next; |
---|
235 | } |
---|
236 | |
---|
237 | nodes[n].next = first_free_node; |
---|
238 | first_free_node = n; |
---|
239 | |
---|
240 | } |
---|
241 | |
---|
242 | void erase(const Edge& edge) { |
---|
243 | int n = edge.id; |
---|
244 | |
---|
245 | if(edges[n].next_in!=-1) { |
---|
246 | edges[edges[n].next_in].prev_in = edges[n].prev_in; |
---|
247 | } |
---|
248 | |
---|
249 | if(edges[n].prev_in!=-1) { |
---|
250 | edges[edges[n].prev_in].next_in = edges[n].next_in; |
---|
251 | } else { |
---|
252 | nodes[edges[n].target].first_in = edges[n].next_in; |
---|
253 | } |
---|
254 | |
---|
255 | |
---|
256 | if(edges[n].next_out!=-1) { |
---|
257 | edges[edges[n].next_out].prev_out = edges[n].prev_out; |
---|
258 | } |
---|
259 | |
---|
260 | if(edges[n].prev_out!=-1) { |
---|
261 | edges[edges[n].prev_out].next_out = edges[n].next_out; |
---|
262 | } else { |
---|
263 | nodes[edges[n].source].first_out = edges[n].next_out; |
---|
264 | } |
---|
265 | |
---|
266 | edges[n].next_in = first_free_edge; |
---|
267 | first_free_edge = n; |
---|
268 | |
---|
269 | } |
---|
270 | |
---|
271 | void clear() { |
---|
272 | edges.clear(); |
---|
273 | nodes.clear(); |
---|
274 | first_node = first_free_node = first_free_edge = -1; |
---|
275 | } |
---|
276 | |
---|
277 | protected: |
---|
278 | void _moveTarget(Edge e, Node n) |
---|
279 | { |
---|
280 | if(edges[e.id].next_in != -1) |
---|
281 | edges[edges[e.id].next_in].prev_in = edges[e.id].prev_in; |
---|
282 | if(edges[e.id].prev_in != -1) |
---|
283 | edges[edges[e.id].prev_in].next_in = edges[e.id].next_in; |
---|
284 | else nodes[edges[e.id].target].first_in = edges[e.id].next_in; |
---|
285 | edges[e.id].target = n.id; |
---|
286 | edges[e.id].prev_in = -1; |
---|
287 | edges[e.id].next_in = nodes[n.id].first_in; |
---|
288 | nodes[n.id].first_in = e.id; |
---|
289 | } |
---|
290 | void _moveSource(Edge e, Node n) |
---|
291 | { |
---|
292 | if(edges[e.id].next_out != -1) |
---|
293 | edges[edges[e.id].next_out].prev_out = edges[e.id].prev_out; |
---|
294 | if(edges[e.id].prev_out != -1) |
---|
295 | edges[edges[e.id].prev_out].next_out = edges[e.id].next_out; |
---|
296 | else nodes[edges[e.id].source].first_out = edges[e.id].next_out; |
---|
297 | edges[e.id].source = n.id; |
---|
298 | edges[e.id].prev_out = -1; |
---|
299 | edges[e.id].next_out = nodes[n.id].first_out; |
---|
300 | nodes[n.id].first_out = e.id; |
---|
301 | } |
---|
302 | |
---|
303 | }; |
---|
304 | |
---|
305 | typedef AlterableGraphExtender<ListGraphBase> AlterableListGraphBase; |
---|
306 | typedef IterableGraphExtender<AlterableListGraphBase> IterableListGraphBase; |
---|
307 | typedef DefaultMappableGraphExtender<IterableListGraphBase> MappableListGraphBase; |
---|
308 | typedef ExtendableGraphExtender<MappableListGraphBase> ExtendableListGraphBase; |
---|
309 | typedef ClearableGraphExtender<ExtendableListGraphBase> ClearableListGraphBase; |
---|
310 | typedef ErasableGraphExtender<ClearableListGraphBase> ErasableListGraphBase; |
---|
311 | |
---|
312 | /// \addtogroup graphs |
---|
313 | /// @{ |
---|
314 | |
---|
315 | ///A list graph class. |
---|
316 | |
---|
317 | ///This is a simple and fast erasable graph implementation. |
---|
318 | /// |
---|
319 | ///It addition that it conforms to the |
---|
320 | ///\ref concept::ErasableGraph "ErasableGraph" concept, |
---|
321 | ///it also provides several additional useful extra functionalities. |
---|
322 | ///\sa concept::ErasableGraph. |
---|
323 | |
---|
324 | class ListGraph : public ErasableListGraphBase |
---|
325 | { |
---|
326 | public: |
---|
327 | /// Moves the target of \c e to \c n |
---|
328 | |
---|
329 | /// Moves the target of \c e to \c n |
---|
330 | /// |
---|
331 | ///\note The <tt>Edge</tt>'s and <tt>OutEdge</tt>'s |
---|
332 | ///referencing the moved edge remain |
---|
333 | ///valid. However <tt>InEdge</tt>'s are invalidated. |
---|
334 | void moveTarget(Edge e, Node n) { _moveTarget(e,n); } |
---|
335 | /// Moves the source of \c e to \c n |
---|
336 | |
---|
337 | /// Moves the source of \c e to \c n |
---|
338 | /// |
---|
339 | ///\note The <tt>Edge</tt>'s and <tt>InEdge</tt>'s |
---|
340 | ///referencing the moved edge remain |
---|
341 | ///valid. However <tt>OutEdge</tt>'s are invalidated. |
---|
342 | void moveSource(Edge e, Node n) { _moveSource(e,n); } |
---|
343 | |
---|
344 | /// Invert the direction of an edge. |
---|
345 | |
---|
346 | ///\note The <tt>Edge</tt>'s |
---|
347 | ///referencing the moved edge remain |
---|
348 | ///valid. However <tt>OutEdge</tt>'s and <tt>InEdge</tt>'s are invalidated. |
---|
349 | void reverseEdge(Edge e) { |
---|
350 | Node t=target(e); |
---|
351 | _moveTarget(e,source(e)); |
---|
352 | _moveSource(e,t); |
---|
353 | } |
---|
354 | |
---|
355 | ///Using this it possible to avoid the superfluous memory allocation. |
---|
356 | |
---|
357 | ///Using this it possible to avoid the superfluous memory allocation. |
---|
358 | ///\todo more docs... |
---|
359 | void reserveEdge(int n) { edges.reserve(n); }; |
---|
360 | |
---|
361 | ///Contract two nodes. |
---|
362 | |
---|
363 | ///This function contracts two nodes. |
---|
364 | /// |
---|
365 | ///Node \p b will be removed but instead of deleting |
---|
366 | ///its neighboring edges, they will be joined to \p a. |
---|
367 | ///The last parameter \p r controls whether to remove loops. \c true |
---|
368 | ///means that loops will be removed. |
---|
369 | /// |
---|
370 | ///\note The <tt>Edge</tt>s |
---|
371 | ///referencing a moved edge remain |
---|
372 | ///valid. However <tt>InEdge</tt>'s and <tt>OutEdge</tt>'s |
---|
373 | ///may be invalidated. |
---|
374 | void contract(Node a,Node b,bool r=true) |
---|
375 | { |
---|
376 | for(OutEdgeIt e(*this,b);e!=INVALID;) { |
---|
377 | OutEdgeIt f=e; |
---|
378 | ++f; |
---|
379 | if(r && target(e)==a) erase(e); |
---|
380 | else moveSource(e,a); |
---|
381 | e=f; |
---|
382 | } |
---|
383 | for(InEdgeIt e(*this,b);e!=INVALID;) { |
---|
384 | InEdgeIt f=e; |
---|
385 | ++f; |
---|
386 | if(r && source(e)==a) erase(e); |
---|
387 | else moveTarget(e,a); |
---|
388 | e=f; |
---|
389 | } |
---|
390 | erase(b); |
---|
391 | } |
---|
392 | |
---|
393 | ///Split a node. |
---|
394 | |
---|
395 | ///This function splits a node. First a new node is added to the graph, |
---|
396 | ///then the source of each outgoing edge of \c n is moved to this new node. |
---|
397 | ///If \c connect is \c true (this is the default value), then a new edge |
---|
398 | ///from \c n to the newly created node is also added. |
---|
399 | ///\return The newly created node. |
---|
400 | /// |
---|
401 | ///\note The <tt>Edge</tt>s |
---|
402 | ///referencing a moved edge remain |
---|
403 | ///valid. However <tt>InEdge</tt>'s and <tt>OutEdge</tt>'s |
---|
404 | ///may be invalidated. |
---|
405 | ///\warning This functionality cannot be used together with the SnapShot |
---|
406 | ///feature. |
---|
407 | ///\todo It could be implemented in a bit faster way. |
---|
408 | Node split(Node n, bool connect = true) |
---|
409 | { |
---|
410 | Node b = addNode(); |
---|
411 | for(OutEdgeIt e(*this,n);e!=INVALID;) { |
---|
412 | OutEdgeIt f=e; |
---|
413 | ++f; |
---|
414 | moveSource(e,b); |
---|
415 | e=f; |
---|
416 | } |
---|
417 | if(connect) addEdge(n,b); |
---|
418 | return b; |
---|
419 | } |
---|
420 | |
---|
421 | ///Class to make a snapshot of the graph and to restrore to it later. |
---|
422 | |
---|
423 | ///Class to make a snapshot of the graph and to restrore to it later. |
---|
424 | /// |
---|
425 | ///The newly added nodes and edges can be removed using the |
---|
426 | ///restore() function. |
---|
427 | /// |
---|
428 | ///\warning Edge and node deletions cannot be restored. |
---|
429 | ///\warning SnapShots cannot be nested. |
---|
430 | ///\todo \c SnapShot or \c Snapshot? |
---|
431 | class SnapShot : protected AlterationNotifier<Node>::ObserverBase, |
---|
432 | protected AlterationNotifier<Edge>::ObserverBase |
---|
433 | { |
---|
434 | protected: |
---|
435 | |
---|
436 | ListGraph *g; |
---|
437 | std::list<Node> added_nodes; |
---|
438 | std::list<Edge> added_edges; |
---|
439 | |
---|
440 | bool active; |
---|
441 | virtual void add(const Node& n) { |
---|
442 | added_nodes.push_back(n); |
---|
443 | }; |
---|
444 | ///\bug Exception... |
---|
445 | /// |
---|
446 | virtual void erase(const Node&) |
---|
447 | { |
---|
448 | exit(1); |
---|
449 | } |
---|
450 | virtual void add(const Edge& n) { |
---|
451 | added_edges.push_back(n); |
---|
452 | }; |
---|
453 | ///\bug Exception... |
---|
454 | /// |
---|
455 | virtual void erase(const Edge&) |
---|
456 | { |
---|
457 | exit(1); |
---|
458 | } |
---|
459 | |
---|
460 | void regist(ListGraph &_g) { |
---|
461 | g=&_g; |
---|
462 | AlterationNotifier<Node>::ObserverBase:: |
---|
463 | attach(g->getNotifier(Node())); |
---|
464 | AlterationNotifier<Edge>::ObserverBase:: |
---|
465 | attach(g->getNotifier(Edge())); |
---|
466 | } |
---|
467 | |
---|
468 | void deregist() { |
---|
469 | AlterationNotifier<Node>::ObserverBase:: |
---|
470 | detach(); |
---|
471 | AlterationNotifier<Edge>::ObserverBase:: |
---|
472 | detach(); |
---|
473 | g=0; |
---|
474 | } |
---|
475 | |
---|
476 | public: |
---|
477 | ///Default constructur. |
---|
478 | |
---|
479 | ///Default constructur. |
---|
480 | ///To actually make a snapshot you must call save(). |
---|
481 | /// |
---|
482 | SnapShot() : g(0) {} |
---|
483 | ///Constructor that immediately makes a snapshot. |
---|
484 | |
---|
485 | ///This constructor immediately makes a snapshot of the graph. |
---|
486 | ///\param _g The graph we make a snapshot of. |
---|
487 | SnapShot(ListGraph &_g) { |
---|
488 | regist(_g); |
---|
489 | } |
---|
490 | ///\bug Is it necessary? |
---|
491 | /// |
---|
492 | ~SnapShot() |
---|
493 | { |
---|
494 | if(g) deregist(); |
---|
495 | } |
---|
496 | |
---|
497 | ///Make a snapshot. |
---|
498 | |
---|
499 | ///Make a snapshot of the graph. |
---|
500 | /// |
---|
501 | ///This function can be called more than once. In case of a repeated |
---|
502 | ///call, the previous snapshot gets lost. |
---|
503 | ///\param _g The graph we make the snapshot of. |
---|
504 | void save(ListGraph &_g) |
---|
505 | { |
---|
506 | if(g!=&_g) { |
---|
507 | if(g) deregist(); |
---|
508 | regist(_g); |
---|
509 | } |
---|
510 | added_nodes.clear(); |
---|
511 | added_edges.clear(); |
---|
512 | } |
---|
513 | |
---|
514 | ///Undo the changes until the last snapshot. |
---|
515 | |
---|
516 | ///Undo the changes until last snapshot created by save(). |
---|
517 | /// |
---|
518 | ///\todo This function might be called undo(). |
---|
519 | void restore() { |
---|
520 | deregist(); |
---|
521 | while(!added_edges.empty()) { |
---|
522 | g->erase(added_edges.front()); |
---|
523 | added_edges.pop_front(); |
---|
524 | } |
---|
525 | while(!added_nodes.empty()) { |
---|
526 | g->erase(added_nodes.front()); |
---|
527 | added_nodes.pop_front(); |
---|
528 | } |
---|
529 | } |
---|
530 | }; |
---|
531 | |
---|
532 | }; |
---|
533 | |
---|
534 | |
---|
535 | /**************** Undirected List Graph ****************/ |
---|
536 | |
---|
537 | typedef ErasableUndirGraphExtender< |
---|
538 | ClearableUndirGraphExtender< |
---|
539 | ExtendableUndirGraphExtender< |
---|
540 | MappableUndirGraphExtender< |
---|
541 | IterableUndirGraphExtender< |
---|
542 | AlterableUndirGraphExtender< |
---|
543 | UndirGraphExtender<ListGraphBase> > > > > > > ErasableUndirListGraphBase; |
---|
544 | |
---|
545 | ///An undirected list graph class. |
---|
546 | |
---|
547 | ///This is a simple and fast erasable undirected graph implementation. |
---|
548 | /// |
---|
549 | ///It conforms to the |
---|
550 | ///\ref concept::UndirGraph "UndirGraph" concept. |
---|
551 | /// |
---|
552 | ///\sa concept::UndirGraph. |
---|
553 | /// |
---|
554 | ///\todo SnapShot, reverseEdge(), moveTarget(), moveSource(), contract() |
---|
555 | ///haven't been implemented yet. |
---|
556 | /// |
---|
557 | class UndirListGraph : public ErasableUndirListGraphBase { |
---|
558 | }; |
---|
559 | |
---|
560 | |
---|
561 | /// @} |
---|
562 | } //namespace lemon |
---|
563 | |
---|
564 | |
---|
565 | #endif |
---|