1 | /* -*- C++ -*- |
---|
2 | * src/lemon/smart_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_SMART_GRAPH_H |
---|
18 | #define LEMON_SMART_GRAPH_H |
---|
19 | |
---|
20 | ///\ingroup graphs |
---|
21 | ///\file |
---|
22 | ///\brief SmartGraph and SymSmartGraph classes. |
---|
23 | |
---|
24 | #include <vector> |
---|
25 | |
---|
26 | #include <lemon/invalid.h> |
---|
27 | |
---|
28 | #include <lemon/bits/clearable_graph_extender.h> |
---|
29 | #include <lemon/bits/extendable_graph_extender.h> |
---|
30 | #include <lemon/bits/iterable_graph_extender.h> |
---|
31 | #include <lemon/bits/alteration_notifier.h> |
---|
32 | #include <lemon/bits/default_map.h> |
---|
33 | |
---|
34 | #include <lemon/bits/undir_graph_extender.h> |
---|
35 | |
---|
36 | #include <lemon/utility.h> |
---|
37 | |
---|
38 | namespace lemon { |
---|
39 | |
---|
40 | class SmartGraph; |
---|
41 | ///Base of SmartGraph |
---|
42 | |
---|
43 | ///Base of SmartGraph |
---|
44 | /// |
---|
45 | class SmartGraphBase { |
---|
46 | |
---|
47 | friend class SmatGraph; |
---|
48 | |
---|
49 | protected: |
---|
50 | struct NodeT |
---|
51 | { |
---|
52 | int first_in,first_out; |
---|
53 | NodeT() : first_in(-1), first_out(-1) {} |
---|
54 | }; |
---|
55 | struct EdgeT |
---|
56 | { |
---|
57 | int target, source, next_in, next_out; |
---|
58 | //FIXME: is this necessary? |
---|
59 | EdgeT() : next_in(-1), next_out(-1) {} |
---|
60 | }; |
---|
61 | |
---|
62 | std::vector<NodeT> nodes; |
---|
63 | |
---|
64 | std::vector<EdgeT> edges; |
---|
65 | |
---|
66 | |
---|
67 | public: |
---|
68 | |
---|
69 | typedef SmartGraphBase Graph; |
---|
70 | |
---|
71 | class Node; |
---|
72 | class Edge; |
---|
73 | |
---|
74 | |
---|
75 | public: |
---|
76 | |
---|
77 | SmartGraphBase() : nodes(), edges() { } |
---|
78 | SmartGraphBase(const SmartGraphBase &_g) : nodes(_g.nodes), edges(_g.edges) { } |
---|
79 | |
---|
80 | typedef True NodeNumTag; |
---|
81 | typedef True EdgeNumTag; |
---|
82 | |
---|
83 | ///Number of nodes. |
---|
84 | int nodeNum() const { return nodes.size(); } |
---|
85 | ///Number of edges. |
---|
86 | int edgeNum() const { return edges.size(); } |
---|
87 | |
---|
88 | /// Maximum node ID. |
---|
89 | |
---|
90 | /// Maximum node ID. |
---|
91 | ///\sa id(Node) |
---|
92 | int maxId(Node = INVALID) const { return nodes.size()-1; } |
---|
93 | /// Maximum edge ID. |
---|
94 | |
---|
95 | /// Maximum edge ID. |
---|
96 | ///\sa id(Edge) |
---|
97 | int maxId(Edge = INVALID) const { return edges.size()-1; } |
---|
98 | |
---|
99 | Node source(Edge e) const { return edges[e.n].source; } |
---|
100 | Node target(Edge e) const { return edges[e.n].target; } |
---|
101 | |
---|
102 | /// Node ID. |
---|
103 | |
---|
104 | /// The ID of a valid Node is a nonnegative integer not greater than |
---|
105 | /// \ref maxNodeId(). The range of the ID's is not surely continuous |
---|
106 | /// and the greatest node ID can be actually less then \ref maxNodeId(). |
---|
107 | /// |
---|
108 | /// The ID of the \ref INVALID node is -1. |
---|
109 | ///\return The ID of the node \c v. |
---|
110 | static int id(Node v) { return v.n; } |
---|
111 | /// Edge ID. |
---|
112 | |
---|
113 | /// The ID of a valid Edge is a nonnegative integer not greater than |
---|
114 | /// \ref maxEdgeId(). The range of the ID's is not surely continuous |
---|
115 | /// and the greatest edge ID can be actually less then \ref maxEdgeId(). |
---|
116 | /// |
---|
117 | /// The ID of the \ref INVALID edge is -1. |
---|
118 | ///\return The ID of the edge \c e. |
---|
119 | static int id(Edge e) { return e.n; } |
---|
120 | |
---|
121 | static Node fromId(int id, Node) { return Node(id);} |
---|
122 | |
---|
123 | static Edge fromId(int id, Edge) { return Edge(id);} |
---|
124 | |
---|
125 | Node addNode() { |
---|
126 | Node n; n.n=nodes.size(); |
---|
127 | nodes.push_back(NodeT()); //FIXME: Hmmm... |
---|
128 | return n; |
---|
129 | } |
---|
130 | |
---|
131 | Edge addEdge(Node u, Node v) { |
---|
132 | Edge e; e.n=edges.size(); edges.push_back(EdgeT()); //FIXME: Hmmm... |
---|
133 | edges[e.n].source=u.n; edges[e.n].target=v.n; |
---|
134 | edges[e.n].next_out=nodes[u.n].first_out; |
---|
135 | edges[e.n].next_in=nodes[v.n].first_in; |
---|
136 | nodes[u.n].first_out=nodes[v.n].first_in=e.n; |
---|
137 | |
---|
138 | return e; |
---|
139 | } |
---|
140 | |
---|
141 | void clear() { |
---|
142 | edges.clear(); |
---|
143 | nodes.clear(); |
---|
144 | } |
---|
145 | |
---|
146 | |
---|
147 | class Node { |
---|
148 | friend class SmartGraphBase; |
---|
149 | friend class SmartGraph; |
---|
150 | |
---|
151 | protected: |
---|
152 | int n; |
---|
153 | ///\todo It should be removed (or at least define a setToId() instead). |
---|
154 | /// |
---|
155 | Node(int nn) {n=nn;} |
---|
156 | public: |
---|
157 | Node() {} |
---|
158 | Node (Invalid) { n=-1; } |
---|
159 | bool operator==(const Node i) const {return n==i.n;} |
---|
160 | bool operator!=(const Node i) const {return n!=i.n;} |
---|
161 | bool operator<(const Node i) const {return n<i.n;} |
---|
162 | }; |
---|
163 | |
---|
164 | |
---|
165 | class Edge { |
---|
166 | friend class SmartGraphBase; |
---|
167 | friend class SmartGraph; |
---|
168 | |
---|
169 | protected: |
---|
170 | int n; |
---|
171 | ///\todo It should be removed (or at least define a setToId() instead). |
---|
172 | /// |
---|
173 | Edge(int nn) {n=nn;} |
---|
174 | public: |
---|
175 | Edge() { } |
---|
176 | Edge (Invalid) { n=-1; } |
---|
177 | bool operator==(const Edge i) const {return n==i.n;} |
---|
178 | bool operator!=(const Edge i) const {return n!=i.n;} |
---|
179 | bool operator<(const Edge i) const {return n<i.n;} |
---|
180 | }; |
---|
181 | |
---|
182 | void first(Node& node) const { |
---|
183 | node.n = nodes.size() - 1; |
---|
184 | } |
---|
185 | |
---|
186 | static void next(Node& node) { |
---|
187 | --node.n; |
---|
188 | } |
---|
189 | |
---|
190 | void first(Edge& edge) const { |
---|
191 | edge.n = edges.size() - 1; |
---|
192 | } |
---|
193 | |
---|
194 | static void next(Edge& edge) { |
---|
195 | --edge.n; |
---|
196 | } |
---|
197 | |
---|
198 | void firstOut(Edge& edge, const Node& node) const { |
---|
199 | edge.n = nodes[node.n].first_out; |
---|
200 | } |
---|
201 | |
---|
202 | void nextOut(Edge& edge) const { |
---|
203 | edge.n = edges[edge.n].next_out; |
---|
204 | } |
---|
205 | |
---|
206 | void firstIn(Edge& edge, const Node& node) const { |
---|
207 | edge.n = nodes[node.n].first_in; |
---|
208 | } |
---|
209 | |
---|
210 | void nextIn(Edge& edge) const { |
---|
211 | edge.n = edges[edge.n].next_in; |
---|
212 | } |
---|
213 | |
---|
214 | Edge _findEdge(Node u,Node v, Edge prev = INVALID) |
---|
215 | { |
---|
216 | int e = (prev.n==-1)? nodes[u.n].first_out : edges[prev.n].next_out; |
---|
217 | while(e!=-1 && edges[e].target!=v.n) e = edges[e].next_out; |
---|
218 | prev.n=e; |
---|
219 | return prev; |
---|
220 | } |
---|
221 | |
---|
222 | Node _split(Node n, bool connect = true) |
---|
223 | { |
---|
224 | Node b = addNode(); |
---|
225 | nodes[b.n].first_out=nodes[n.n].first_out; |
---|
226 | nodes[n.n].first_out=-1; |
---|
227 | for(int i=nodes[b.n].first_out;i!=-1;i++) edges[i].source=b.n; |
---|
228 | if(connect) addEdge(n,b); |
---|
229 | return b; |
---|
230 | } |
---|
231 | |
---|
232 | }; |
---|
233 | |
---|
234 | typedef AlterableGraphExtender<SmartGraphBase> AlterableSmartGraphBase; |
---|
235 | typedef IterableGraphExtender<AlterableSmartGraphBase> IterableSmartGraphBase; |
---|
236 | typedef DefaultMappableGraphExtender<IterableSmartGraphBase> MappableSmartGraphBase; |
---|
237 | typedef ExtendableGraphExtender<MappableSmartGraphBase> ExtendableSmartGraphBase; |
---|
238 | typedef ClearableGraphExtender<ExtendableSmartGraphBase> ClearableSmartGraphBase; |
---|
239 | |
---|
240 | /// \addtogroup graphs |
---|
241 | /// @{ |
---|
242 | |
---|
243 | ///A smart graph class. |
---|
244 | |
---|
245 | ///This is a simple and fast graph implementation. |
---|
246 | ///It is also quite memory efficient, but at the price |
---|
247 | ///that <b> it does support only limited (only stack-like) |
---|
248 | ///node and edge deletions</b>. |
---|
249 | ///It conforms to |
---|
250 | ///the \ref concept::ExtendableGraph "ExtendableGraph" concept. |
---|
251 | ///\sa concept::ExtendableGraph. |
---|
252 | /// |
---|
253 | ///\author Alpar Juttner |
---|
254 | class SmartGraph : public ClearableSmartGraphBase { |
---|
255 | public: |
---|
256 | /// Finds an edge between two nodes. |
---|
257 | |
---|
258 | /// Finds an edge from node \c u to node \c v. |
---|
259 | /// |
---|
260 | /// If \c prev is \ref INVALID (this is the default value), then |
---|
261 | /// it finds the first edge from \c u to \c v. Otherwise it looks for |
---|
262 | /// the next edge from \c u to \c v after \c prev. |
---|
263 | /// \return The found edge or \ref INVALID if there is no such an edge. |
---|
264 | /// |
---|
265 | /// Thus you can iterate through each edge from \c u to \c v as it follows. |
---|
266 | /// \code |
---|
267 | /// for(Edge e=G.findEdge(u,v);e!=INVALID;e=G.findEdge(u,v,e)) { |
---|
268 | /// ... |
---|
269 | /// } |
---|
270 | /// \endcode |
---|
271 | /// \todo Possibly it should be a global function. |
---|
272 | Edge findEdge(Node u,Node v, Edge prev = INVALID) |
---|
273 | { |
---|
274 | return _findEdge(u,v,prev); |
---|
275 | } |
---|
276 | |
---|
277 | class SnapShot; |
---|
278 | friend class SnapShot; |
---|
279 | |
---|
280 | protected: |
---|
281 | void restoreSnapShot(const SnapShot &s) |
---|
282 | { |
---|
283 | while(s.edge_num>edges.size()) { |
---|
284 | Parent::getNotifier(Edge()).erase(Edge(edges.size()-1)); |
---|
285 | nodes[edges.back().target].first_in=edges.back().next_in; |
---|
286 | nodes[edges.back().source].first_out=edges.back().next_out; |
---|
287 | edges.pop_back(); |
---|
288 | } |
---|
289 | //nodes.resize(s.nodes_num); |
---|
290 | while(s.node_num>nodes.size()) { |
---|
291 | Parent::getNotifier(Node()).erase(Node(nodes.size()-1)); |
---|
292 | nodes.pop_back(); |
---|
293 | } |
---|
294 | } |
---|
295 | |
---|
296 | public: |
---|
297 | |
---|
298 | ///Split a node. |
---|
299 | |
---|
300 | ///This function splits a node. First a new node is added to the graph, |
---|
301 | ///then the source of each outgoing edge of \c n is moved to this new node. |
---|
302 | ///If \c connect is \c true (this is the default value), then a new edge |
---|
303 | ///from \c n to the newly created node is also added. |
---|
304 | ///\return The newly created node. |
---|
305 | /// |
---|
306 | ///\note The <tt>Edge</tt>s |
---|
307 | ///referencing a moved edge remain |
---|
308 | ///valid. However <tt>InEdge</tt>'s and <tt>OutEdge</tt>'s |
---|
309 | ///may be invalidated. |
---|
310 | ///\warning This functionality cannot be used together with the SnapShot |
---|
311 | ///feature. |
---|
312 | ///\todo It could be implemented in a bit faster way. |
---|
313 | Node split(Node n, bool connect = true) |
---|
314 | { |
---|
315 | return _split(n,connect); |
---|
316 | } |
---|
317 | |
---|
318 | |
---|
319 | ///Class to make a snapshot of the graph and to restrore to it later. |
---|
320 | |
---|
321 | ///Class to make a snapshot of the graph and to restrore to it later. |
---|
322 | /// |
---|
323 | ///The newly added nodes and edges can be removed using the |
---|
324 | ///restore() function. |
---|
325 | ///\note After you restore a state, you cannot restore |
---|
326 | ///a later state, in other word you cannot add again the edges deleted |
---|
327 | ///by restore() using another SnapShot instance. |
---|
328 | /// |
---|
329 | class SnapShot |
---|
330 | { |
---|
331 | SmartGraph *g; |
---|
332 | protected: |
---|
333 | friend class SmartGraph; |
---|
334 | unsigned int node_num; |
---|
335 | unsigned int edge_num; |
---|
336 | public: |
---|
337 | ///Default constructor. |
---|
338 | |
---|
339 | ///Default constructor. |
---|
340 | ///To actually make a snapshot you must call save(). |
---|
341 | /// |
---|
342 | SnapShot() : g(0) {} |
---|
343 | ///Constructor that immediately makes a snapshot |
---|
344 | |
---|
345 | ///This constructor immediately makes a snapshot of the graph. |
---|
346 | ///\param _g The graph we make a snapshot of. |
---|
347 | SnapShot(SmartGraph &_g) :g(&_g) { |
---|
348 | node_num=g->nodes.size(); |
---|
349 | edge_num=g->edges.size(); |
---|
350 | } |
---|
351 | |
---|
352 | ///Make a snapshot. |
---|
353 | |
---|
354 | ///Make a snapshot of the graph. |
---|
355 | /// |
---|
356 | ///This function can be called more than once. In case of a repeated |
---|
357 | ///call, the previous snapshot gets lost. |
---|
358 | ///\param _g The graph we make the snapshot of. |
---|
359 | void save(SmartGraph &_g) |
---|
360 | { |
---|
361 | g=&_g; |
---|
362 | node_num=g->nodes.size(); |
---|
363 | edge_num=g->edges.size(); |
---|
364 | } |
---|
365 | |
---|
366 | ///Undo the changes until a snapshot. |
---|
367 | |
---|
368 | ///Undo the changes until a snapshot created by save(). |
---|
369 | /// |
---|
370 | ///\param s an internal stucture given back by save() |
---|
371 | ///\note After you restored a state, you cannot restore |
---|
372 | ///a later state, in other word you cannot add again the edges deleted |
---|
373 | ///by restore(). |
---|
374 | /// |
---|
375 | ///\todo This function might be called undo(). |
---|
376 | |
---|
377 | void restore() |
---|
378 | { |
---|
379 | g->restoreSnapShot(*this); |
---|
380 | } |
---|
381 | }; |
---|
382 | }; |
---|
383 | |
---|
384 | |
---|
385 | /**************** Undirected List Graph ****************/ |
---|
386 | |
---|
387 | typedef ClearableUndirGraphExtender< |
---|
388 | ExtendableUndirGraphExtender< |
---|
389 | MappableUndirGraphExtender< |
---|
390 | IterableUndirGraphExtender< |
---|
391 | AlterableUndirGraphExtender< |
---|
392 | UndirGraphExtender<SmartGraphBase> > > > > > UndirSmartGraphBase; |
---|
393 | |
---|
394 | ///A smart undirected graph class. |
---|
395 | |
---|
396 | ///This is a simple and fast undirected graph implementation. |
---|
397 | ///It is also quite memory efficient, but at the price |
---|
398 | ///that <b> it does support only limited (only stack-like) |
---|
399 | ///node and edge deletions</b>. |
---|
400 | ///Except from this it conforms to |
---|
401 | ///the \ref concept::UndirGraph "UndirGraph" concept. |
---|
402 | ///\sa concept::UndirGraph. |
---|
403 | /// |
---|
404 | ///\todo SnapShot hasn't been implemented yet. |
---|
405 | /// |
---|
406 | class UndirSmartGraph : public UndirSmartGraphBase { |
---|
407 | }; |
---|
408 | |
---|
409 | |
---|
410 | /// @} |
---|
411 | } //namespace lemon |
---|
412 | |
---|
413 | |
---|
414 | #endif //LEMON_SMART_GRAPH_H |
---|