1 | /* -*- C++ -*- |
---|
2 | * src/lemon/graph_adaptor.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_GRAPH_ADAPTOR_H |
---|
18 | #define LEMON_GRAPH_ADAPTOR_H |
---|
19 | |
---|
20 | ///\ingroup graph_adaptors |
---|
21 | ///\file |
---|
22 | ///\brief Several graph adaptors. |
---|
23 | /// |
---|
24 | ///This file contains several useful graph adaptor functions. |
---|
25 | /// |
---|
26 | ///\author Marton Makai |
---|
27 | |
---|
28 | #include <lemon/invalid.h> |
---|
29 | #include <lemon/maps.h> |
---|
30 | #include <lemon/bits/iterable_graph_extender.h> |
---|
31 | #include <lemon/bits/undir_graph_extender.h> |
---|
32 | #include <iostream> |
---|
33 | |
---|
34 | namespace lemon { |
---|
35 | |
---|
36 | // Graph adaptors |
---|
37 | |
---|
38 | /*! |
---|
39 | \addtogroup graph_adaptors |
---|
40 | @{ |
---|
41 | */ |
---|
42 | |
---|
43 | /*! |
---|
44 | Base type for the Graph Adaptors |
---|
45 | |
---|
46 | \warning Graph adaptors are in even more experimental state than the other |
---|
47 | parts of the lib. Use them at you own risk. |
---|
48 | |
---|
49 | This is the base type for most of LEMON graph adaptors. |
---|
50 | This class implements a trivial graph adaptor i.e. it only wraps the |
---|
51 | functions and types of the graph. The purpose of this class is to |
---|
52 | make easier implementing graph adaptors. E.g. if an adaptor is |
---|
53 | considered which differs from the wrapped graph only in some of its |
---|
54 | functions or types, then it can be derived from GraphAdaptor, and only the |
---|
55 | differences should be implemented. |
---|
56 | |
---|
57 | \author Marton Makai |
---|
58 | */ |
---|
59 | template<typename _Graph> |
---|
60 | class GraphAdaptorBase { |
---|
61 | public: |
---|
62 | typedef _Graph Graph; |
---|
63 | /// \todo Is it needed? |
---|
64 | typedef Graph BaseGraph; |
---|
65 | typedef Graph ParentGraph; |
---|
66 | |
---|
67 | protected: |
---|
68 | Graph* graph; |
---|
69 | GraphAdaptorBase() : graph(0) { } |
---|
70 | void setGraph(Graph& _graph) { graph=&_graph; } |
---|
71 | |
---|
72 | public: |
---|
73 | GraphAdaptorBase(Graph& _graph) : graph(&_graph) { } |
---|
74 | |
---|
75 | typedef typename Graph::Node Node; |
---|
76 | typedef typename Graph::Edge Edge; |
---|
77 | |
---|
78 | void first(Node& i) const { graph->first(i); } |
---|
79 | void first(Edge& i) const { graph->first(i); } |
---|
80 | void firstIn(Edge& i, const Node& n) const { graph->firstIn(i, n); } |
---|
81 | void firstOut(Edge& i, const Node& n ) const { graph->firstOut(i, n); } |
---|
82 | |
---|
83 | void next(Node& i) const { graph->next(i); } |
---|
84 | void next(Edge& i) const { graph->next(i); } |
---|
85 | void nextIn(Edge& i) const { graph->nextIn(i); } |
---|
86 | void nextOut(Edge& i) const { graph->nextOut(i); } |
---|
87 | |
---|
88 | Node source(const Edge& e) const { return graph->source(e); } |
---|
89 | Node target(const Edge& e) const { return graph->target(e); } |
---|
90 | |
---|
91 | int nodeNum() const { return graph->nodeNum(); } |
---|
92 | int edgeNum() const { return graph->edgeNum(); } |
---|
93 | |
---|
94 | Node addNode() const { return Node(graph->addNode()); } |
---|
95 | Edge addEdge(const Node& source, const Node& target) const { |
---|
96 | return Edge(graph->addEdge(source, target)); } |
---|
97 | |
---|
98 | void erase(const Node& i) const { graph->erase(i); } |
---|
99 | void erase(const Edge& i) const { graph->erase(i); } |
---|
100 | |
---|
101 | void clear() const { graph->clear(); } |
---|
102 | |
---|
103 | bool forward(const Edge& e) const { return graph->forward(e); } |
---|
104 | bool backward(const Edge& e) const { return graph->backward(e); } |
---|
105 | |
---|
106 | int id(const Node& v) const { return graph->id(v); } |
---|
107 | int id(const Edge& e) const { return graph->id(e); } |
---|
108 | |
---|
109 | Edge opposite(const Edge& e) const { return Edge(graph->opposite(e)); } |
---|
110 | |
---|
111 | template <typename _Value> |
---|
112 | class NodeMap : public _Graph::template NodeMap<_Value> { |
---|
113 | public: |
---|
114 | typedef typename _Graph::template NodeMap<_Value> Parent; |
---|
115 | NodeMap(const GraphAdaptorBase<_Graph>& gw) : Parent(*gw.graph) { } |
---|
116 | NodeMap(const GraphAdaptorBase<_Graph>& gw, const _Value& value) |
---|
117 | : Parent(*gw.graph, value) { } |
---|
118 | }; |
---|
119 | |
---|
120 | template <typename _Value> |
---|
121 | class EdgeMap : public _Graph::template EdgeMap<_Value> { |
---|
122 | public: |
---|
123 | typedef typename _Graph::template EdgeMap<_Value> Parent; |
---|
124 | EdgeMap(const GraphAdaptorBase<_Graph>& gw) : Parent(*gw.graph) { } |
---|
125 | EdgeMap(const GraphAdaptorBase<_Graph>& gw, const _Value& value) |
---|
126 | : Parent(*gw.graph, value) { } |
---|
127 | }; |
---|
128 | |
---|
129 | }; |
---|
130 | |
---|
131 | template <typename _Graph> |
---|
132 | class GraphAdaptor : |
---|
133 | public IterableGraphExtender<GraphAdaptorBase<_Graph> > { |
---|
134 | public: |
---|
135 | typedef _Graph Graph; |
---|
136 | typedef IterableGraphExtender<GraphAdaptorBase<_Graph> > Parent; |
---|
137 | protected: |
---|
138 | GraphAdaptor() : Parent() { } |
---|
139 | |
---|
140 | public: |
---|
141 | GraphAdaptor(Graph& _graph) { setGraph(_graph); } |
---|
142 | }; |
---|
143 | |
---|
144 | template <typename _Graph> |
---|
145 | class RevGraphAdaptorBase : public GraphAdaptorBase<_Graph> { |
---|
146 | public: |
---|
147 | typedef _Graph Graph; |
---|
148 | typedef GraphAdaptorBase<_Graph> Parent; |
---|
149 | protected: |
---|
150 | RevGraphAdaptorBase() : Parent() { } |
---|
151 | public: |
---|
152 | typedef typename Parent::Node Node; |
---|
153 | typedef typename Parent::Edge Edge; |
---|
154 | |
---|
155 | // using Parent::first; |
---|
156 | void firstIn(Edge& i, const Node& n) const { Parent::firstOut(i, n); } |
---|
157 | void firstOut(Edge& i, const Node& n ) const { Parent::firstIn(i, n); } |
---|
158 | |
---|
159 | // using Parent::next; |
---|
160 | void nextIn(Edge& i) const { Parent::nextOut(i); } |
---|
161 | void nextOut(Edge& i) const { Parent::nextIn(i); } |
---|
162 | |
---|
163 | Node source(const Edge& e) const { return Parent::target(e); } |
---|
164 | Node target(const Edge& e) const { return Parent::source(e); } |
---|
165 | }; |
---|
166 | |
---|
167 | |
---|
168 | /// A graph adaptor which reverses the orientation of the edges. |
---|
169 | |
---|
170 | ///\warning Graph adaptors are in even more experimental state than the other |
---|
171 | ///parts of the lib. Use them at you own risk. |
---|
172 | /// |
---|
173 | /// Let \f$G=(V, A)\f$ be a directed graph and |
---|
174 | /// suppose that a graph instange \c g of type |
---|
175 | /// \c ListGraph implements \f$G\f$. |
---|
176 | /// \code |
---|
177 | /// ListGraph g; |
---|
178 | /// \endcode |
---|
179 | /// For each directed edge |
---|
180 | /// \f$e\in A\f$, let \f$\bar e\f$ denote the edge obtained by |
---|
181 | /// reversing its orientation. |
---|
182 | /// Then RevGraphAdaptor implements the graph structure with node-set |
---|
183 | /// \f$V\f$ and edge-set |
---|
184 | /// \f$\{\bar e : e\in A \}\f$, i.e. the graph obtained from \f$G\f$ be |
---|
185 | /// reversing the orientation of its edges. The following code shows how |
---|
186 | /// such an instance can be constructed. |
---|
187 | /// \code |
---|
188 | /// RevGraphAdaptor<ListGraph> gw(g); |
---|
189 | /// \endcode |
---|
190 | ///\author Marton Makai |
---|
191 | template<typename _Graph> |
---|
192 | class RevGraphAdaptor : |
---|
193 | public IterableGraphExtender<RevGraphAdaptorBase<_Graph> > { |
---|
194 | public: |
---|
195 | typedef _Graph Graph; |
---|
196 | typedef IterableGraphExtender< |
---|
197 | RevGraphAdaptorBase<_Graph> > Parent; |
---|
198 | protected: |
---|
199 | RevGraphAdaptor() { } |
---|
200 | public: |
---|
201 | RevGraphAdaptor(_Graph& _graph) { setGraph(_graph); } |
---|
202 | }; |
---|
203 | |
---|
204 | |
---|
205 | template <typename _Graph, typename NodeFilterMap, typename EdgeFilterMap> |
---|
206 | class SubGraphAdaptorBase : public GraphAdaptorBase<_Graph> { |
---|
207 | public: |
---|
208 | typedef _Graph Graph; |
---|
209 | typedef GraphAdaptorBase<_Graph> Parent; |
---|
210 | protected: |
---|
211 | NodeFilterMap* node_filter_map; |
---|
212 | EdgeFilterMap* edge_filter_map; |
---|
213 | SubGraphAdaptorBase() : Parent(), |
---|
214 | node_filter_map(0), edge_filter_map(0) { } |
---|
215 | |
---|
216 | void setNodeFilterMap(NodeFilterMap& _node_filter_map) { |
---|
217 | node_filter_map=&_node_filter_map; |
---|
218 | } |
---|
219 | void setEdgeFilterMap(EdgeFilterMap& _edge_filter_map) { |
---|
220 | edge_filter_map=&_edge_filter_map; |
---|
221 | } |
---|
222 | |
---|
223 | public: |
---|
224 | // SubGraphAdaptorBase(Graph& _graph, |
---|
225 | // NodeFilterMap& _node_filter_map, |
---|
226 | // EdgeFilterMap& _edge_filter_map) : |
---|
227 | // Parent(&_graph), |
---|
228 | // node_filter_map(&node_filter_map), |
---|
229 | // edge_filter_map(&edge_filter_map) { } |
---|
230 | |
---|
231 | typedef typename Parent::Node Node; |
---|
232 | typedef typename Parent::Edge Edge; |
---|
233 | |
---|
234 | void first(Node& i) const { |
---|
235 | Parent::first(i); |
---|
236 | while (i!=INVALID && !(*node_filter_map)[i]) Parent::next(i); |
---|
237 | } |
---|
238 | void first(Edge& i) const { |
---|
239 | Parent::first(i); |
---|
240 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::next(i); |
---|
241 | } |
---|
242 | void firstIn(Edge& i, const Node& n) const { |
---|
243 | Parent::firstIn(i, n); |
---|
244 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextIn(i); |
---|
245 | } |
---|
246 | void firstOut(Edge& i, const Node& n) const { |
---|
247 | Parent::firstOut(i, n); |
---|
248 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextOut(i); |
---|
249 | } |
---|
250 | |
---|
251 | void next(Node& i) const { |
---|
252 | Parent::next(i); |
---|
253 | while (i!=INVALID && !(*node_filter_map)[i]) Parent::next(i); |
---|
254 | } |
---|
255 | void next(Edge& i) const { |
---|
256 | Parent::next(i); |
---|
257 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::next(i); |
---|
258 | } |
---|
259 | void nextIn(Edge& i) const { |
---|
260 | Parent::nextIn(i); |
---|
261 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextIn(i); |
---|
262 | } |
---|
263 | void nextOut(Edge& i) const { |
---|
264 | Parent::nextOut(i); |
---|
265 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextOut(i); |
---|
266 | } |
---|
267 | |
---|
268 | /// This function hides \c n in the graph, i.e. the iteration |
---|
269 | /// jumps over it. This is done by simply setting the value of \c n |
---|
270 | /// to be false in the corresponding node-map. |
---|
271 | void hide(const Node& n) const { node_filter_map->set(n, false); } |
---|
272 | |
---|
273 | /// This function hides \c e in the graph, i.e. the iteration |
---|
274 | /// jumps over it. This is done by simply setting the value of \c e |
---|
275 | /// to be false in the corresponding edge-map. |
---|
276 | void hide(const Edge& e) const { edge_filter_map->set(e, false); } |
---|
277 | |
---|
278 | /// The value of \c n is set to be true in the node-map which stores |
---|
279 | /// hide information. If \c n was hidden previuosly, then it is shown |
---|
280 | /// again |
---|
281 | void unHide(const Node& n) const { node_filter_map->set(n, true); } |
---|
282 | |
---|
283 | /// The value of \c e is set to be true in the edge-map which stores |
---|
284 | /// hide information. If \c e was hidden previuosly, then it is shown |
---|
285 | /// again |
---|
286 | void unHide(const Edge& e) const { edge_filter_map->set(e, true); } |
---|
287 | |
---|
288 | /// Returns true if \c n is hidden. |
---|
289 | bool hidden(const Node& n) const { return !(*node_filter_map)[n]; } |
---|
290 | |
---|
291 | /// Returns true if \c n is hidden. |
---|
292 | bool hidden(const Edge& e) const { return !(*edge_filter_map)[e]; } |
---|
293 | |
---|
294 | /// \warning This is a linear time operation and works only if s |
---|
295 | /// \c Graph::NodeIt is defined. |
---|
296 | /// \todo assign tags. |
---|
297 | int nodeNum() const { |
---|
298 | int i=0; |
---|
299 | Node n; |
---|
300 | for (first(n); n!=INVALID; next(n)) ++i; |
---|
301 | return i; |
---|
302 | } |
---|
303 | |
---|
304 | /// \warning This is a linear time operation and works only if |
---|
305 | /// \c Graph::EdgeIt is defined. |
---|
306 | /// \todo assign tags. |
---|
307 | int edgeNum() const { |
---|
308 | int i=0; |
---|
309 | Edge e; |
---|
310 | for (first(e); e!=INVALID; next(e)) ++i; |
---|
311 | return i; |
---|
312 | } |
---|
313 | |
---|
314 | |
---|
315 | }; |
---|
316 | |
---|
317 | /*! \brief A graph adaptor for hiding nodes and edges from a graph. |
---|
318 | |
---|
319 | \warning Graph adaptors are in even more experimental state than the other |
---|
320 | parts of the lib. Use them at you own risk. |
---|
321 | |
---|
322 | SubGraphAdaptor shows the graph with filtered node-set and |
---|
323 | edge-set. |
---|
324 | Let \f$G=(V, A)\f$ be a directed graph |
---|
325 | and suppose that the graph instance \c g of type ListGraph implements |
---|
326 | \f$G\f$. |
---|
327 | Let moreover \f$b_V\f$ and |
---|
328 | \f$b_A\f$ be bool-valued functions resp. on the node-set and edge-set. |
---|
329 | SubGraphAdaptor<...>::NodeIt iterates |
---|
330 | on the node-set \f$\{v\in V : b_V(v)=true\}\f$ and |
---|
331 | SubGraphAdaptor<...>::EdgeIt iterates |
---|
332 | on the edge-set \f$\{e\in A : b_A(e)=true\}\f$. Similarly, |
---|
333 | SubGraphAdaptor<...>::OutEdgeIt and SubGraphAdaptor<...>::InEdgeIt iterates |
---|
334 | only on edges leaving and entering a specific node which have true value. |
---|
335 | |
---|
336 | We have to note that this does not mean that an |
---|
337 | induced subgraph is obtained, the node-iterator cares only the filter |
---|
338 | on the node-set, and the edge-iterators care only the filter on the |
---|
339 | edge-set. |
---|
340 | \code |
---|
341 | typedef ListGraph Graph; |
---|
342 | Graph g; |
---|
343 | typedef Graph::Node Node; |
---|
344 | typedef Graph::Edge Edge; |
---|
345 | Node u=g.addNode(); //node of id 0 |
---|
346 | Node v=g.addNode(); //node of id 1 |
---|
347 | Node e=g.addEdge(u, v); //edge of id 0 |
---|
348 | Node f=g.addEdge(v, u); //edge of id 1 |
---|
349 | Graph::NodeMap<bool> nm(g, true); |
---|
350 | nm.set(u, false); |
---|
351 | Graph::EdgeMap<bool> em(g, true); |
---|
352 | em.set(e, false); |
---|
353 | typedef SubGraphAdaptor<Graph, Graph::NodeMap<bool>, Graph::EdgeMap<bool> > SubGW; |
---|
354 | SubGW gw(g, nm, em); |
---|
355 | for (SubGW::NodeIt n(gw); n!=INVALID; ++n) std::cout << g.id(n) << std::endl; |
---|
356 | std::cout << ":-)" << std::endl; |
---|
357 | for (SubGW::EdgeIt e(gw); e!=INVALID; ++e) std::cout << g.id(e) << std::endl; |
---|
358 | \endcode |
---|
359 | The output of the above code is the following. |
---|
360 | \code |
---|
361 | 1 |
---|
362 | :-) |
---|
363 | 1 |
---|
364 | \endcode |
---|
365 | Note that \c n is of type \c SubGW::NodeIt, but it can be converted to |
---|
366 | \c Graph::Node that is why \c g.id(n) can be applied. |
---|
367 | |
---|
368 | For other examples see also the documentation of NodeSubGraphAdaptor and |
---|
369 | EdgeSubGraphAdaptor. |
---|
370 | |
---|
371 | \author Marton Makai |
---|
372 | */ |
---|
373 | template<typename _Graph, typename NodeFilterMap, |
---|
374 | typename EdgeFilterMap> |
---|
375 | class SubGraphAdaptor : |
---|
376 | public IterableGraphExtender< |
---|
377 | SubGraphAdaptorBase<_Graph, NodeFilterMap, EdgeFilterMap> > { |
---|
378 | public: |
---|
379 | typedef _Graph Graph; |
---|
380 | typedef IterableGraphExtender< |
---|
381 | SubGraphAdaptorBase<_Graph, NodeFilterMap, EdgeFilterMap> > Parent; |
---|
382 | protected: |
---|
383 | SubGraphAdaptor() { } |
---|
384 | public: |
---|
385 | SubGraphAdaptor(_Graph& _graph, NodeFilterMap& _node_filter_map, |
---|
386 | EdgeFilterMap& _edge_filter_map) { |
---|
387 | setGraph(_graph); |
---|
388 | setNodeFilterMap(_node_filter_map); |
---|
389 | setEdgeFilterMap(_edge_filter_map); |
---|
390 | } |
---|
391 | }; |
---|
392 | |
---|
393 | |
---|
394 | |
---|
395 | /*! \brief An adaptor for hiding nodes from a graph. |
---|
396 | |
---|
397 | \warning Graph adaptors are in even more experimental state than the other |
---|
398 | parts of the lib. Use them at you own risk. |
---|
399 | |
---|
400 | An adaptor for hiding nodes from a graph. |
---|
401 | This adaptor specializes SubGraphAdaptor in the way that only the node-set |
---|
402 | can be filtered. Note that this does not mean of considering induced |
---|
403 | subgraph, the edge-iterators consider the original edge-set. |
---|
404 | \author Marton Makai |
---|
405 | */ |
---|
406 | template<typename Graph, typename NodeFilterMap> |
---|
407 | class NodeSubGraphAdaptor : |
---|
408 | public SubGraphAdaptor<Graph, NodeFilterMap, |
---|
409 | ConstMap<typename Graph::Edge,bool> > { |
---|
410 | public: |
---|
411 | typedef SubGraphAdaptor<Graph, NodeFilterMap, |
---|
412 | ConstMap<typename Graph::Edge,bool> > Parent; |
---|
413 | protected: |
---|
414 | ConstMap<typename Graph::Edge, bool> const_true_map; |
---|
415 | public: |
---|
416 | NodeSubGraphAdaptor(Graph& _graph, NodeFilterMap& _node_filter_map) : |
---|
417 | Parent(), const_true_map(true) { |
---|
418 | Parent::setGraph(_graph); |
---|
419 | Parent::setNodeFilterMap(_node_filter_map); |
---|
420 | Parent::setEdgeFilterMap(const_true_map); |
---|
421 | } |
---|
422 | }; |
---|
423 | |
---|
424 | |
---|
425 | /*! \brief An adaptor for hiding edges from a graph. |
---|
426 | |
---|
427 | \warning Graph adaptors are in even more experimental state than the other |
---|
428 | parts of the lib. Use them at you own risk. |
---|
429 | |
---|
430 | An adaptor for hiding edges from a graph. |
---|
431 | This adaptor specializes SubGraphAdaptor in the way that only the edge-set |
---|
432 | can be filtered. The usefulness of this adaptor is demonstrated in the |
---|
433 | problem of searching a maximum number of edge-disjoint shortest paths |
---|
434 | between |
---|
435 | two nodes \c s and \c t. Shortest here means being shortest w.r.t. |
---|
436 | non-negative edge-lengths. Note that |
---|
437 | the comprehension of the presented solution |
---|
438 | need's some elementary knowledge from combinatorial optimization. |
---|
439 | |
---|
440 | If a single shortest path is to be |
---|
441 | searched between \c s and \c t, then this can be done easily by |
---|
442 | applying the Dijkstra algorithm. What happens, if a maximum number of |
---|
443 | edge-disjoint shortest paths is to be computed. It can be proved that an |
---|
444 | edge can be in a shortest path if and only if it is tight with respect to |
---|
445 | the potential function computed by Dijkstra. Moreover, any path containing |
---|
446 | only such edges is a shortest one. Thus we have to compute a maximum number |
---|
447 | of edge-disjoint paths between \c s and \c t in the graph which has edge-set |
---|
448 | all the tight edges. The computation will be demonstrated on the following |
---|
449 | graph, which is read from a dimacs file. |
---|
450 | |
---|
451 | \dot |
---|
452 | digraph lemon_dot_example { |
---|
453 | node [ shape=ellipse, fontname=Helvetica, fontsize=10 ]; |
---|
454 | n0 [ label="0 (s)" ]; |
---|
455 | n1 [ label="1" ]; |
---|
456 | n2 [ label="2" ]; |
---|
457 | n3 [ label="3" ]; |
---|
458 | n4 [ label="4" ]; |
---|
459 | n5 [ label="5" ]; |
---|
460 | n6 [ label="6 (t)" ]; |
---|
461 | edge [ shape=ellipse, fontname=Helvetica, fontsize=10 ]; |
---|
462 | n5 -> n6 [ label="9, length:4" ]; |
---|
463 | n4 -> n6 [ label="8, length:2" ]; |
---|
464 | n3 -> n5 [ label="7, length:1" ]; |
---|
465 | n2 -> n5 [ label="6, length:3" ]; |
---|
466 | n2 -> n6 [ label="5, length:5" ]; |
---|
467 | n2 -> n4 [ label="4, length:2" ]; |
---|
468 | n1 -> n4 [ label="3, length:3" ]; |
---|
469 | n0 -> n3 [ label="2, length:1" ]; |
---|
470 | n0 -> n2 [ label="1, length:2" ]; |
---|
471 | n0 -> n1 [ label="0, length:3" ]; |
---|
472 | } |
---|
473 | \enddot |
---|
474 | |
---|
475 | \code |
---|
476 | Graph g; |
---|
477 | Node s, t; |
---|
478 | LengthMap length(g); |
---|
479 | |
---|
480 | readDimacs(std::cin, g, length, s, t); |
---|
481 | |
---|
482 | cout << "edges with lengths (of form id, source--length->target): " << endl; |
---|
483 | for(EdgeIt e(g); e!=INVALID; ++e) |
---|
484 | cout << g.id(e) << ", " << g.id(g.source(e)) << "--" |
---|
485 | << length[e] << "->" << g.id(g.target(e)) << endl; |
---|
486 | |
---|
487 | cout << "s: " << g.id(s) << " t: " << g.id(t) << endl; |
---|
488 | \endcode |
---|
489 | Next, the potential function is computed with Dijkstra. |
---|
490 | \code |
---|
491 | typedef Dijkstra<Graph, LengthMap> Dijkstra; |
---|
492 | Dijkstra dijkstra(g, length); |
---|
493 | dijkstra.run(s); |
---|
494 | \endcode |
---|
495 | Next, we consrtruct a map which filters the edge-set to the tight edges. |
---|
496 | \code |
---|
497 | typedef TightEdgeFilterMap<Graph, const Dijkstra::DistMap, LengthMap> |
---|
498 | TightEdgeFilter; |
---|
499 | TightEdgeFilter tight_edge_filter(g, dijkstra.distMap(), length); |
---|
500 | |
---|
501 | typedef EdgeSubGraphAdaptor<Graph, TightEdgeFilter> SubGW; |
---|
502 | SubGW gw(g, tight_edge_filter); |
---|
503 | \endcode |
---|
504 | Then, the maximum nimber of edge-disjoint \c s-\c t paths are computed |
---|
505 | with a max flow algorithm Preflow. |
---|
506 | \code |
---|
507 | ConstMap<Edge, int> const_1_map(1); |
---|
508 | Graph::EdgeMap<int> flow(g, 0); |
---|
509 | |
---|
510 | Preflow<SubGW, int, ConstMap<Edge, int>, Graph::EdgeMap<int> > |
---|
511 | preflow(gw, s, t, const_1_map, flow); |
---|
512 | preflow.run(); |
---|
513 | \endcode |
---|
514 | Last, the output is: |
---|
515 | \code |
---|
516 | cout << "maximum number of edge-disjoint shortest path: " |
---|
517 | << preflow.flowValue() << endl; |
---|
518 | cout << "edges of the maximum number of edge-disjoint shortest s-t paths: " |
---|
519 | << endl; |
---|
520 | for(EdgeIt e(g); e!=INVALID; ++e) |
---|
521 | if (flow[e]) |
---|
522 | cout << " " << g.id(g.source(e)) << "--" |
---|
523 | << length[e] << "->" << g.id(g.target(e)) << endl; |
---|
524 | \endcode |
---|
525 | The program has the following (expected :-)) output: |
---|
526 | \code |
---|
527 | edges with lengths (of form id, source--length->target): |
---|
528 | 9, 5--4->6 |
---|
529 | 8, 4--2->6 |
---|
530 | 7, 3--1->5 |
---|
531 | 6, 2--3->5 |
---|
532 | 5, 2--5->6 |
---|
533 | 4, 2--2->4 |
---|
534 | 3, 1--3->4 |
---|
535 | 2, 0--1->3 |
---|
536 | 1, 0--2->2 |
---|
537 | 0, 0--3->1 |
---|
538 | s: 0 t: 6 |
---|
539 | maximum number of edge-disjoint shortest path: 2 |
---|
540 | edges of the maximum number of edge-disjoint shortest s-t paths: |
---|
541 | 9, 5--4->6 |
---|
542 | 8, 4--2->6 |
---|
543 | 7, 3--1->5 |
---|
544 | 4, 2--2->4 |
---|
545 | 2, 0--1->3 |
---|
546 | 1, 0--2->2 |
---|
547 | \endcode |
---|
548 | |
---|
549 | \author Marton Makai |
---|
550 | */ |
---|
551 | template<typename Graph, typename EdgeFilterMap> |
---|
552 | class EdgeSubGraphAdaptor : |
---|
553 | public SubGraphAdaptor<Graph, ConstMap<typename Graph::Node,bool>, |
---|
554 | EdgeFilterMap> { |
---|
555 | public: |
---|
556 | typedef SubGraphAdaptor<Graph, ConstMap<typename Graph::Node,bool>, |
---|
557 | EdgeFilterMap> Parent; |
---|
558 | protected: |
---|
559 | ConstMap<typename Graph::Node, bool> const_true_map; |
---|
560 | public: |
---|
561 | EdgeSubGraphAdaptor(Graph& _graph, EdgeFilterMap& _edge_filter_map) : |
---|
562 | Parent(), const_true_map(true) { |
---|
563 | Parent::setGraph(_graph); |
---|
564 | Parent::setNodeFilterMap(const_true_map); |
---|
565 | Parent::setEdgeFilterMap(_edge_filter_map); |
---|
566 | } |
---|
567 | }; |
---|
568 | |
---|
569 | template <typename _Graph> |
---|
570 | class UndirGraphAdaptorBase : |
---|
571 | public UndirGraphExtender<GraphAdaptorBase<_Graph> > { |
---|
572 | public: |
---|
573 | typedef _Graph Graph; |
---|
574 | typedef UndirGraphExtender<GraphAdaptorBase<_Graph> > Parent; |
---|
575 | protected: |
---|
576 | UndirGraphAdaptorBase() : Parent() { } |
---|
577 | public: |
---|
578 | typedef typename Parent::UndirEdge UndirEdge; |
---|
579 | typedef typename Parent::Edge Edge; |
---|
580 | |
---|
581 | /// \bug Why cant an edge say that it is forward or not??? |
---|
582 | /// By this, a pointer to the graph have to be stored |
---|
583 | /// The implementation |
---|
584 | template <typename T> |
---|
585 | class EdgeMap { |
---|
586 | protected: |
---|
587 | const UndirGraphAdaptorBase<_Graph>* g; |
---|
588 | template <typename TT> friend class EdgeMap; |
---|
589 | typename _Graph::template EdgeMap<T> forward_map, backward_map; |
---|
590 | public: |
---|
591 | typedef T Value; |
---|
592 | typedef Edge Key; |
---|
593 | |
---|
594 | EdgeMap(const UndirGraphAdaptorBase<_Graph>& _g) : g(&_g), |
---|
595 | forward_map(*(g->graph)), backward_map(*(g->graph)) { } |
---|
596 | |
---|
597 | EdgeMap(const UndirGraphAdaptorBase<_Graph>& _g, T a) : g(&_g), |
---|
598 | forward_map(*(g->graph), a), backward_map(*(g->graph), a) { } |
---|
599 | |
---|
600 | void set(Edge e, T a) { |
---|
601 | if (g->forward(e)) |
---|
602 | forward_map.set(e, a); |
---|
603 | else |
---|
604 | backward_map.set(e, a); |
---|
605 | } |
---|
606 | |
---|
607 | T operator[](Edge e) const { |
---|
608 | if (g->forward(e)) |
---|
609 | return forward_map[e]; |
---|
610 | else |
---|
611 | return backward_map[e]; |
---|
612 | } |
---|
613 | }; |
---|
614 | |
---|
615 | template <typename T> |
---|
616 | class UndirEdgeMap { |
---|
617 | template <typename TT> friend class UndirEdgeMap; |
---|
618 | typename _Graph::template EdgeMap<T> map; |
---|
619 | public: |
---|
620 | typedef T Value; |
---|
621 | typedef UndirEdge Key; |
---|
622 | |
---|
623 | UndirEdgeMap(const UndirGraphAdaptorBase<_Graph>& g) : |
---|
624 | map(*(g.graph)) { } |
---|
625 | |
---|
626 | UndirEdgeMap(const UndirGraphAdaptorBase<_Graph>& g, T a) : |
---|
627 | map(*(g.graph), a) { } |
---|
628 | |
---|
629 | void set(UndirEdge e, T a) { |
---|
630 | map.set(e, a); |
---|
631 | } |
---|
632 | |
---|
633 | T operator[](UndirEdge e) const { |
---|
634 | return map[e]; |
---|
635 | } |
---|
636 | }; |
---|
637 | |
---|
638 | }; |
---|
639 | |
---|
640 | /// \brief An undirected graph is made from a directed graph by an adaptor |
---|
641 | /// |
---|
642 | /// Undocumented, untested!!! |
---|
643 | /// If somebody knows nice demo application, let's polulate it. |
---|
644 | /// |
---|
645 | /// \author Marton Makai |
---|
646 | template<typename _Graph> |
---|
647 | class UndirGraphAdaptor : |
---|
648 | public IterableUndirGraphExtender< |
---|
649 | UndirGraphAdaptorBase<_Graph> > { |
---|
650 | public: |
---|
651 | typedef _Graph Graph; |
---|
652 | typedef IterableUndirGraphExtender< |
---|
653 | UndirGraphAdaptorBase<_Graph> > Parent; |
---|
654 | protected: |
---|
655 | UndirGraphAdaptor() { } |
---|
656 | public: |
---|
657 | UndirGraphAdaptor(_Graph& _graph) { |
---|
658 | setGraph(_graph); |
---|
659 | } |
---|
660 | }; |
---|
661 | |
---|
662 | |
---|
663 | template <typename _Graph, |
---|
664 | typename ForwardFilterMap, typename BackwardFilterMap> |
---|
665 | class SubBidirGraphAdaptorBase : public GraphAdaptorBase<_Graph> { |
---|
666 | public: |
---|
667 | typedef _Graph Graph; |
---|
668 | typedef GraphAdaptorBase<_Graph> Parent; |
---|
669 | protected: |
---|
670 | ForwardFilterMap* forward_filter; |
---|
671 | BackwardFilterMap* backward_filter; |
---|
672 | SubBidirGraphAdaptorBase() : Parent(), |
---|
673 | forward_filter(0), backward_filter(0) { } |
---|
674 | |
---|
675 | void setForwardFilterMap(ForwardFilterMap& _forward_filter) { |
---|
676 | forward_filter=&_forward_filter; |
---|
677 | } |
---|
678 | void setBackwardFilterMap(BackwardFilterMap& _backward_filter) { |
---|
679 | backward_filter=&_backward_filter; |
---|
680 | } |
---|
681 | |
---|
682 | public: |
---|
683 | // SubGraphAdaptorBase(Graph& _graph, |
---|
684 | // NodeFilterMap& _node_filter_map, |
---|
685 | // EdgeFilterMap& _edge_filter_map) : |
---|
686 | // Parent(&_graph), |
---|
687 | // node_filter_map(&node_filter_map), |
---|
688 | // edge_filter_map(&edge_filter_map) { } |
---|
689 | |
---|
690 | typedef typename Parent::Node Node; |
---|
691 | typedef typename _Graph::Edge GraphEdge; |
---|
692 | template <typename T> class EdgeMap; |
---|
693 | /// SubBidirGraphAdaptorBase<..., ..., ...>::Edge is inherited from |
---|
694 | /// _Graph::Edge. It contains an extra bool flag which is true |
---|
695 | /// if and only if the |
---|
696 | /// edge is the backward version of the original edge. |
---|
697 | class Edge : public _Graph::Edge { |
---|
698 | friend class SubBidirGraphAdaptorBase< |
---|
699 | Graph, ForwardFilterMap, BackwardFilterMap>; |
---|
700 | template<typename T> friend class EdgeMap; |
---|
701 | protected: |
---|
702 | bool backward; //true, iff backward |
---|
703 | public: |
---|
704 | Edge() { } |
---|
705 | /// \todo =false is needed, or causes problems? |
---|
706 | /// If \c _backward is false, then we get an edge corresponding to the |
---|
707 | /// original one, otherwise its oppositely directed pair is obtained. |
---|
708 | Edge(const typename _Graph::Edge& e, bool _backward/*=false*/) : |
---|
709 | _Graph::Edge(e), backward(_backward) { } |
---|
710 | Edge(Invalid i) : _Graph::Edge(i), backward(true) { } |
---|
711 | bool operator==(const Edge& v) const { |
---|
712 | return (this->backward==v.backward && |
---|
713 | static_cast<typename _Graph::Edge>(*this)== |
---|
714 | static_cast<typename _Graph::Edge>(v)); |
---|
715 | } |
---|
716 | bool operator!=(const Edge& v) const { |
---|
717 | return (this->backward!=v.backward || |
---|
718 | static_cast<typename _Graph::Edge>(*this)!= |
---|
719 | static_cast<typename _Graph::Edge>(v)); |
---|
720 | } |
---|
721 | }; |
---|
722 | |
---|
723 | void first(Node& i) const { |
---|
724 | Parent::first(i); |
---|
725 | } |
---|
726 | |
---|
727 | void first(Edge& i) const { |
---|
728 | Parent::first(i); |
---|
729 | i.backward=false; |
---|
730 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
731 | !(*forward_filter)[i]) Parent::next(i); |
---|
732 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
733 | Parent::first(i); |
---|
734 | i.backward=true; |
---|
735 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
736 | !(*backward_filter)[i]) Parent::next(i); |
---|
737 | } |
---|
738 | } |
---|
739 | |
---|
740 | void firstIn(Edge& i, const Node& n) const { |
---|
741 | Parent::firstIn(i, n); |
---|
742 | i.backward=false; |
---|
743 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
744 | !(*forward_filter)[i]) Parent::nextIn(i); |
---|
745 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
746 | Parent::firstOut(i, n); |
---|
747 | i.backward=true; |
---|
748 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
749 | !(*backward_filter)[i]) Parent::nextOut(i); |
---|
750 | } |
---|
751 | } |
---|
752 | |
---|
753 | void firstOut(Edge& i, const Node& n) const { |
---|
754 | Parent::firstOut(i, n); |
---|
755 | i.backward=false; |
---|
756 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
757 | !(*forward_filter)[i]) Parent::nextOut(i); |
---|
758 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
759 | Parent::firstIn(i, n); |
---|
760 | i.backward=true; |
---|
761 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
762 | !(*backward_filter)[i]) Parent::nextIn(i); |
---|
763 | } |
---|
764 | } |
---|
765 | |
---|
766 | void next(Node& i) const { |
---|
767 | Parent::next(i); |
---|
768 | } |
---|
769 | |
---|
770 | void next(Edge& i) const { |
---|
771 | if (!(i.backward)) { |
---|
772 | Parent::next(i); |
---|
773 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
774 | !(*forward_filter)[i]) Parent::next(i); |
---|
775 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
776 | Parent::first(i); |
---|
777 | i.backward=true; |
---|
778 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
779 | !(*backward_filter)[i]) Parent::next(i); |
---|
780 | } |
---|
781 | } else { |
---|
782 | Parent::next(i); |
---|
783 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
784 | !(*backward_filter)[i]) Parent::next(i); |
---|
785 | } |
---|
786 | } |
---|
787 | |
---|
788 | void nextIn(Edge& i) const { |
---|
789 | if (!(i.backward)) { |
---|
790 | Node n=Parent::target(i); |
---|
791 | Parent::nextIn(i); |
---|
792 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
793 | !(*forward_filter)[i]) Parent::nextIn(i); |
---|
794 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
795 | Parent::firstOut(i, n); |
---|
796 | i.backward=true; |
---|
797 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
798 | !(*backward_filter)[i]) Parent::nextOut(i); |
---|
799 | } |
---|
800 | } else { |
---|
801 | Parent::nextOut(i); |
---|
802 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
803 | !(*backward_filter)[i]) Parent::nextOut(i); |
---|
804 | } |
---|
805 | } |
---|
806 | |
---|
807 | void nextOut(Edge& i) const { |
---|
808 | if (!(i.backward)) { |
---|
809 | Node n=Parent::source(i); |
---|
810 | Parent::nextOut(i); |
---|
811 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
812 | !(*forward_filter)[i]) Parent::nextOut(i); |
---|
813 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
814 | Parent::firstIn(i, n); |
---|
815 | i.backward=true; |
---|
816 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
817 | !(*backward_filter)[i]) Parent::nextIn(i); |
---|
818 | } |
---|
819 | } else { |
---|
820 | Parent::nextIn(i); |
---|
821 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
822 | !(*backward_filter)[i]) Parent::nextIn(i); |
---|
823 | } |
---|
824 | } |
---|
825 | |
---|
826 | Node source(Edge e) const { |
---|
827 | return ((!e.backward) ? this->graph->source(e) : this->graph->target(e)); } |
---|
828 | Node target(Edge e) const { |
---|
829 | return ((!e.backward) ? this->graph->target(e) : this->graph->source(e)); } |
---|
830 | |
---|
831 | /// Gives back the opposite edge. |
---|
832 | Edge opposite(const Edge& e) const { |
---|
833 | Edge f=e; |
---|
834 | f.backward=!f.backward; |
---|
835 | return f; |
---|
836 | } |
---|
837 | |
---|
838 | /// \warning This is a linear time operation and works only if |
---|
839 | /// \c Graph::EdgeIt is defined. |
---|
840 | /// \todo hmm |
---|
841 | int edgeNum() const { |
---|
842 | int i=0; |
---|
843 | Edge e; |
---|
844 | for (first(e); e!=INVALID; next(e)) ++i; |
---|
845 | return i; |
---|
846 | } |
---|
847 | |
---|
848 | bool forward(const Edge& e) const { return !e.backward; } |
---|
849 | bool backward(const Edge& e) const { return e.backward; } |
---|
850 | |
---|
851 | template <typename T> |
---|
852 | /// \c SubBidirGraphAdaptorBase<..., ..., ...>::EdgeMap contains two |
---|
853 | /// _Graph::EdgeMap one for the forward edges and |
---|
854 | /// one for the backward edges. |
---|
855 | class EdgeMap { |
---|
856 | template <typename TT> friend class EdgeMap; |
---|
857 | typename _Graph::template EdgeMap<T> forward_map, backward_map; |
---|
858 | public: |
---|
859 | typedef T Value; |
---|
860 | typedef Edge Key; |
---|
861 | |
---|
862 | EdgeMap(const SubBidirGraphAdaptorBase<_Graph, |
---|
863 | ForwardFilterMap, BackwardFilterMap>& g) : |
---|
864 | forward_map(*(g.graph)), backward_map(*(g.graph)) { } |
---|
865 | |
---|
866 | EdgeMap(const SubBidirGraphAdaptorBase<_Graph, |
---|
867 | ForwardFilterMap, BackwardFilterMap>& g, T a) : |
---|
868 | forward_map(*(g.graph), a), backward_map(*(g.graph), a) { } |
---|
869 | |
---|
870 | void set(Edge e, T a) { |
---|
871 | if (!e.backward) |
---|
872 | forward_map.set(e, a); |
---|
873 | else |
---|
874 | backward_map.set(e, a); |
---|
875 | } |
---|
876 | |
---|
877 | // typename _Graph::template EdgeMap<T>::ConstReference |
---|
878 | // operator[](Edge e) const { |
---|
879 | // if (!e.backward) |
---|
880 | // return forward_map[e]; |
---|
881 | // else |
---|
882 | // return backward_map[e]; |
---|
883 | // } |
---|
884 | |
---|
885 | // typename _Graph::template EdgeMap<T>::Reference |
---|
886 | T operator[](Edge e) const { |
---|
887 | if (!e.backward) |
---|
888 | return forward_map[e]; |
---|
889 | else |
---|
890 | return backward_map[e]; |
---|
891 | } |
---|
892 | |
---|
893 | void update() { |
---|
894 | forward_map.update(); |
---|
895 | backward_map.update(); |
---|
896 | } |
---|
897 | }; |
---|
898 | |
---|
899 | }; |
---|
900 | |
---|
901 | |
---|
902 | ///\brief An adaptor for composing a subgraph of a |
---|
903 | /// bidirected graph made from a directed one. |
---|
904 | /// |
---|
905 | /// An adaptor for composing a subgraph of a |
---|
906 | /// bidirected graph made from a directed one. |
---|
907 | /// |
---|
908 | ///\warning Graph adaptors are in even more experimental state than the other |
---|
909 | ///parts of the lib. Use them at you own risk. |
---|
910 | /// |
---|
911 | /// Let \f$G=(V, A)\f$ be a directed graph and for each directed edge |
---|
912 | /// \f$e\in A\f$, let \f$\bar e\f$ denote the edge obtained by |
---|
913 | /// reversing its orientation. We are given moreover two bool valued |
---|
914 | /// maps on the edge-set, |
---|
915 | /// \f$forward\_filter\f$, and \f$backward\_filter\f$. |
---|
916 | /// SubBidirGraphAdaptor implements the graph structure with node-set |
---|
917 | /// \f$V\f$ and edge-set |
---|
918 | /// \f$\{e : e\in A \mbox{ and } forward\_filter(e) \mbox{ is true}\}+\{\bar e : e\in A \mbox{ and } backward\_filter(e) \mbox{ is true}\}\f$. |
---|
919 | /// The purpose of writing + instead of union is because parallel |
---|
920 | /// edges can arise. (Similarly, antiparallel edges also can arise). |
---|
921 | /// In other words, a subgraph of the bidirected graph obtained, which |
---|
922 | /// is given by orienting the edges of the original graph in both directions. |
---|
923 | /// As the oppositely directed edges are logically different, |
---|
924 | /// the maps are able to attach different values for them. |
---|
925 | /// |
---|
926 | /// An example for such a construction is \c RevGraphAdaptor where the |
---|
927 | /// forward_filter is everywhere false and the backward_filter is |
---|
928 | /// everywhere true. We note that for sake of efficiency, |
---|
929 | /// \c RevGraphAdaptor is implemented in a different way. |
---|
930 | /// But BidirGraphAdaptor is obtained from |
---|
931 | /// SubBidirGraphAdaptor by considering everywhere true |
---|
932 | /// valued maps both for forward_filter and backward_filter. |
---|
933 | /// |
---|
934 | /// The most important application of SubBidirGraphAdaptor |
---|
935 | /// is ResGraphAdaptor, which stands for the residual graph in directed |
---|
936 | /// flow and circulation problems. |
---|
937 | /// As adaptors usually, the SubBidirGraphAdaptor implements the |
---|
938 | /// above mentioned graph structure without its physical storage, |
---|
939 | /// that is the whole stuff is stored in constant memory. |
---|
940 | template<typename _Graph, |
---|
941 | typename ForwardFilterMap, typename BackwardFilterMap> |
---|
942 | class SubBidirGraphAdaptor : |
---|
943 | public IterableGraphExtender< |
---|
944 | SubBidirGraphAdaptorBase<_Graph, ForwardFilterMap, BackwardFilterMap> > { |
---|
945 | public: |
---|
946 | typedef _Graph Graph; |
---|
947 | typedef IterableGraphExtender< |
---|
948 | SubBidirGraphAdaptorBase< |
---|
949 | _Graph, ForwardFilterMap, BackwardFilterMap> > Parent; |
---|
950 | protected: |
---|
951 | SubBidirGraphAdaptor() { } |
---|
952 | public: |
---|
953 | SubBidirGraphAdaptor(_Graph& _graph, ForwardFilterMap& _forward_filter, |
---|
954 | BackwardFilterMap& _backward_filter) { |
---|
955 | setGraph(_graph); |
---|
956 | setForwardFilterMap(_forward_filter); |
---|
957 | setBackwardFilterMap(_backward_filter); |
---|
958 | } |
---|
959 | }; |
---|
960 | |
---|
961 | |
---|
962 | |
---|
963 | ///\brief An adaptor for composing bidirected graph from a directed one. |
---|
964 | /// |
---|
965 | ///\warning Graph adaptors are in even more experimental state than the other |
---|
966 | ///parts of the lib. Use them at you own risk. |
---|
967 | /// |
---|
968 | /// An adaptor for composing bidirected graph from a directed one. |
---|
969 | /// A bidirected graph is composed over the directed one without physical |
---|
970 | /// storage. As the oppositely directed edges are logically different ones |
---|
971 | /// the maps are able to attach different values for them. |
---|
972 | template<typename Graph> |
---|
973 | class BidirGraphAdaptor : |
---|
974 | public SubBidirGraphAdaptor< |
---|
975 | Graph, |
---|
976 | ConstMap<typename Graph::Edge, bool>, |
---|
977 | ConstMap<typename Graph::Edge, bool> > { |
---|
978 | public: |
---|
979 | typedef SubBidirGraphAdaptor< |
---|
980 | Graph, |
---|
981 | ConstMap<typename Graph::Edge, bool>, |
---|
982 | ConstMap<typename Graph::Edge, bool> > Parent; |
---|
983 | protected: |
---|
984 | ConstMap<typename Graph::Edge, bool> cm; |
---|
985 | |
---|
986 | BidirGraphAdaptor() : Parent(), cm(true) { |
---|
987 | Parent::setForwardFilterMap(cm); |
---|
988 | Parent::setBackwardFilterMap(cm); |
---|
989 | } |
---|
990 | public: |
---|
991 | BidirGraphAdaptor(Graph& _graph) : Parent(), cm(true) { |
---|
992 | Parent::setGraph(_graph); |
---|
993 | Parent::setForwardFilterMap(cm); |
---|
994 | Parent::setBackwardFilterMap(cm); |
---|
995 | } |
---|
996 | |
---|
997 | int edgeNum() const { |
---|
998 | return 2*this->graph->edgeNum(); |
---|
999 | } |
---|
1000 | // KEEP_MAPS(Parent, BidirGraphAdaptor); |
---|
1001 | }; |
---|
1002 | |
---|
1003 | |
---|
1004 | template<typename Graph, typename Number, |
---|
1005 | typename CapacityMap, typename FlowMap> |
---|
1006 | class ResForwardFilter { |
---|
1007 | // const Graph* graph; |
---|
1008 | const CapacityMap* capacity; |
---|
1009 | const FlowMap* flow; |
---|
1010 | public: |
---|
1011 | ResForwardFilter(/*const Graph& _graph, */ |
---|
1012 | const CapacityMap& _capacity, const FlowMap& _flow) : |
---|
1013 | /*graph(&_graph),*/ capacity(&_capacity), flow(&_flow) { } |
---|
1014 | ResForwardFilter() : /*graph(0),*/ capacity(0), flow(0) { } |
---|
1015 | void setCapacity(const CapacityMap& _capacity) { capacity=&_capacity; } |
---|
1016 | void setFlow(const FlowMap& _flow) { flow=&_flow; } |
---|
1017 | bool operator[](const typename Graph::Edge& e) const { |
---|
1018 | return (Number((*flow)[e]) < Number((*capacity)[e])); |
---|
1019 | } |
---|
1020 | }; |
---|
1021 | |
---|
1022 | template<typename Graph, typename Number, |
---|
1023 | typename CapacityMap, typename FlowMap> |
---|
1024 | class ResBackwardFilter { |
---|
1025 | const CapacityMap* capacity; |
---|
1026 | const FlowMap* flow; |
---|
1027 | public: |
---|
1028 | ResBackwardFilter(/*const Graph& _graph,*/ |
---|
1029 | const CapacityMap& _capacity, const FlowMap& _flow) : |
---|
1030 | /*graph(&_graph),*/ capacity(&_capacity), flow(&_flow) { } |
---|
1031 | ResBackwardFilter() : /*graph(0),*/ capacity(0), flow(0) { } |
---|
1032 | void setCapacity(const CapacityMap& _capacity) { capacity=&_capacity; } |
---|
1033 | void setFlow(const FlowMap& _flow) { flow=&_flow; } |
---|
1034 | bool operator[](const typename Graph::Edge& e) const { |
---|
1035 | return (Number(0) < Number((*flow)[e])); |
---|
1036 | } |
---|
1037 | }; |
---|
1038 | |
---|
1039 | |
---|
1040 | /*! \brief An adaptor for composing the residual graph for directed flow and circulation problems. |
---|
1041 | |
---|
1042 | An adaptor for composing the residual graph for directed flow and circulation problems. |
---|
1043 | Let \f$G=(V, A)\f$ be a directed graph and let \f$F\f$ be a |
---|
1044 | number type. Let moreover |
---|
1045 | \f$f,c:A\to F\f$, be functions on the edge-set. |
---|
1046 | In the appications of ResGraphAdaptor, \f$f\f$ usually stands for a flow |
---|
1047 | and \f$c\f$ for a capacity function. |
---|
1048 | Suppose that a graph instange \c g of type |
---|
1049 | \c ListGraph implements \f$G\f$. |
---|
1050 | \code |
---|
1051 | ListGraph g; |
---|
1052 | \endcode |
---|
1053 | Then RevGraphAdaptor implements the graph structure with node-set |
---|
1054 | \f$V\f$ and edge-set \f$A_{forward}\cup A_{backward}\f$, where |
---|
1055 | \f$A_{forward}=\{uv : uv\in A, f(uv)<c(uv)\}\f$ and |
---|
1056 | \f$A_{backward}=\{vu : uv\in A, f(uv)>0\}\f$, |
---|
1057 | i.e. the so called residual graph. |
---|
1058 | When we take the union \f$A_{forward}\cup A_{backward}\f$, |
---|
1059 | multilicities are counted, i.e. if an edge is in both |
---|
1060 | \f$A_{forward}\f$ and \f$A_{backward}\f$, then in the adaptor it |
---|
1061 | appears twice. |
---|
1062 | The following code shows how |
---|
1063 | such an instance can be constructed. |
---|
1064 | \code |
---|
1065 | typedef ListGraph Graph; |
---|
1066 | Graph::EdgeMap<int> f(g); |
---|
1067 | Graph::EdgeMap<int> c(g); |
---|
1068 | ResGraphAdaptor<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > gw(g); |
---|
1069 | \endcode |
---|
1070 | \author Marton Makai |
---|
1071 | */ |
---|
1072 | template<typename Graph, typename Number, |
---|
1073 | typename CapacityMap, typename FlowMap> |
---|
1074 | class ResGraphAdaptor : |
---|
1075 | public SubBidirGraphAdaptor< |
---|
1076 | Graph, |
---|
1077 | ResForwardFilter<Graph, Number, CapacityMap, FlowMap>, |
---|
1078 | ResBackwardFilter<Graph, Number, CapacityMap, FlowMap> > { |
---|
1079 | public: |
---|
1080 | typedef SubBidirGraphAdaptor< |
---|
1081 | Graph, |
---|
1082 | ResForwardFilter<Graph, Number, CapacityMap, FlowMap>, |
---|
1083 | ResBackwardFilter<Graph, Number, CapacityMap, FlowMap> > Parent; |
---|
1084 | protected: |
---|
1085 | const CapacityMap* capacity; |
---|
1086 | FlowMap* flow; |
---|
1087 | ResForwardFilter<Graph, Number, CapacityMap, FlowMap> forward_filter; |
---|
1088 | ResBackwardFilter<Graph, Number, CapacityMap, FlowMap> backward_filter; |
---|
1089 | ResGraphAdaptor() : Parent(), |
---|
1090 | capacity(0), flow(0) { } |
---|
1091 | void setCapacityMap(const CapacityMap& _capacity) { |
---|
1092 | capacity=&_capacity; |
---|
1093 | forward_filter.setCapacity(_capacity); |
---|
1094 | backward_filter.setCapacity(_capacity); |
---|
1095 | } |
---|
1096 | void setFlowMap(FlowMap& _flow) { |
---|
1097 | flow=&_flow; |
---|
1098 | forward_filter.setFlow(_flow); |
---|
1099 | backward_filter.setFlow(_flow); |
---|
1100 | } |
---|
1101 | public: |
---|
1102 | ResGraphAdaptor(Graph& _graph, const CapacityMap& _capacity, |
---|
1103 | FlowMap& _flow) : |
---|
1104 | Parent(), capacity(&_capacity), flow(&_flow), |
---|
1105 | forward_filter(/*_graph,*/ _capacity, _flow), |
---|
1106 | backward_filter(/*_graph,*/ _capacity, _flow) { |
---|
1107 | Parent::setGraph(_graph); |
---|
1108 | Parent::setForwardFilterMap(forward_filter); |
---|
1109 | Parent::setBackwardFilterMap(backward_filter); |
---|
1110 | } |
---|
1111 | |
---|
1112 | typedef typename Parent::Edge Edge; |
---|
1113 | |
---|
1114 | void augment(const Edge& e, Number a) const { |
---|
1115 | if (Parent::forward(e)) |
---|
1116 | flow->set(e, (*flow)[e]+a); |
---|
1117 | else |
---|
1118 | flow->set(e, (*flow)[e]-a); |
---|
1119 | } |
---|
1120 | |
---|
1121 | /// \brief Residual capacity map. |
---|
1122 | /// |
---|
1123 | /// In generic residual graphs the residual capacity can be obtained |
---|
1124 | /// as a map. |
---|
1125 | class ResCap { |
---|
1126 | protected: |
---|
1127 | const ResGraphAdaptor<Graph, Number, CapacityMap, FlowMap>* res_graph; |
---|
1128 | public: |
---|
1129 | typedef Number Value; |
---|
1130 | typedef Edge Key; |
---|
1131 | ResCap(const ResGraphAdaptor<Graph, Number, CapacityMap, FlowMap>& |
---|
1132 | _res_graph) : res_graph(&_res_graph) { } |
---|
1133 | Number operator[](const Edge& e) const { |
---|
1134 | if (res_graph->forward(e)) |
---|
1135 | return (*(res_graph->capacity))[e]-(*(res_graph->flow))[e]; |
---|
1136 | else |
---|
1137 | return (*(res_graph->flow))[e]; |
---|
1138 | } |
---|
1139 | }; |
---|
1140 | |
---|
1141 | // KEEP_MAPS(Parent, ResGraphAdaptor); |
---|
1142 | }; |
---|
1143 | |
---|
1144 | |
---|
1145 | |
---|
1146 | template <typename _Graph, typename FirstOutEdgesMap> |
---|
1147 | class ErasingFirstGraphAdaptorBase : public GraphAdaptorBase<_Graph> { |
---|
1148 | public: |
---|
1149 | typedef _Graph Graph; |
---|
1150 | typedef GraphAdaptorBase<_Graph> Parent; |
---|
1151 | protected: |
---|
1152 | FirstOutEdgesMap* first_out_edges; |
---|
1153 | ErasingFirstGraphAdaptorBase() : Parent(), |
---|
1154 | first_out_edges(0) { } |
---|
1155 | |
---|
1156 | void setFirstOutEdgesMap(FirstOutEdgesMap& _first_out_edges) { |
---|
1157 | first_out_edges=&_first_out_edges; |
---|
1158 | } |
---|
1159 | |
---|
1160 | public: |
---|
1161 | |
---|
1162 | typedef typename Parent::Node Node; |
---|
1163 | typedef typename Parent::Edge Edge; |
---|
1164 | |
---|
1165 | void firstOut(Edge& i, const Node& n) const { |
---|
1166 | i=(*first_out_edges)[n]; |
---|
1167 | } |
---|
1168 | |
---|
1169 | void erase(const Edge& e) const { |
---|
1170 | Node n=source(e); |
---|
1171 | Edge f=e; |
---|
1172 | Parent::nextOut(f); |
---|
1173 | first_out_edges->set(n, f); |
---|
1174 | } |
---|
1175 | }; |
---|
1176 | |
---|
1177 | |
---|
1178 | /// For blocking flows. |
---|
1179 | |
---|
1180 | ///\warning Graph adaptors are in even more experimental state than the other |
---|
1181 | ///parts of the lib. Use them at you own risk. |
---|
1182 | /// |
---|
1183 | /// This graph adaptor is used for on-the-fly |
---|
1184 | /// Dinits blocking flow computations. |
---|
1185 | /// For each node, an out-edge is stored which is used when the |
---|
1186 | /// \code |
---|
1187 | /// OutEdgeIt& first(OutEdgeIt&, const Node&) |
---|
1188 | /// \endcode |
---|
1189 | /// is called. |
---|
1190 | /// |
---|
1191 | /// \author Marton Makai |
---|
1192 | template <typename _Graph, typename FirstOutEdgesMap> |
---|
1193 | class ErasingFirstGraphAdaptor : |
---|
1194 | public IterableGraphExtender< |
---|
1195 | ErasingFirstGraphAdaptorBase<_Graph, FirstOutEdgesMap> > { |
---|
1196 | public: |
---|
1197 | typedef _Graph Graph; |
---|
1198 | typedef IterableGraphExtender< |
---|
1199 | ErasingFirstGraphAdaptorBase<_Graph, FirstOutEdgesMap> > Parent; |
---|
1200 | ErasingFirstGraphAdaptor(Graph& _graph, |
---|
1201 | FirstOutEdgesMap& _first_out_edges) { |
---|
1202 | setGraph(_graph); |
---|
1203 | setFirstOutEdgesMap(_first_out_edges); |
---|
1204 | } |
---|
1205 | |
---|
1206 | }; |
---|
1207 | |
---|
1208 | ///@} |
---|
1209 | |
---|
1210 | } //namespace lemon |
---|
1211 | |
---|
1212 | #endif //LEMON_GRAPH_ADAPTOR_H |
---|
1213 | |
---|