1.1 --- a/lemon/bfs.h Thu Sep 11 11:10:44 2008 +0100
1.2 +++ b/lemon/bfs.h Mon Sep 22 15:33:23 2008 +0200
1.3 @@ -28,6 +28,7 @@
1.4 #include <lemon/core.h>
1.5 #include <lemon/error.h>
1.6 #include <lemon/maps.h>
1.7 +#include <lemon/path.h>
1.8
1.9 namespace lemon {
1.10
1.11 @@ -115,7 +116,7 @@
1.12 ///\ingroup search
1.13 ///This class provides an efficient implementation of the %BFS algorithm.
1.14 ///
1.15 - ///There is also a \ref bfs() "function type interface" for the BFS
1.16 + ///There is also a \ref bfs() "function-type interface" for the BFS
1.17 ///algorithm, which is convenient in the simplier cases and it can be
1.18 ///used easier.
1.19 ///
1.20 @@ -841,26 +842,23 @@
1.21 ///The type of the map that stores the predecessor
1.22 ///arcs of the shortest paths.
1.23 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
1.24 - typedef NullMap<typename Digraph::Node,typename Digraph::Arc> PredMap;
1.25 + typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
1.26 ///Instantiates a \ref PredMap.
1.27
1.28 ///This function instantiates a \ref PredMap.
1.29 ///\param g is the digraph, to which we would like to define the
1.30 ///\ref PredMap.
1.31 ///\todo The digraph alone may be insufficient to initialize
1.32 -#ifdef DOXYGEN
1.33 static PredMap *createPredMap(const Digraph &g)
1.34 -#else
1.35 - static PredMap *createPredMap(const Digraph &)
1.36 -#endif
1.37 {
1.38 - return new PredMap();
1.39 + return new PredMap(g);
1.40 }
1.41
1.42 ///The type of the map that indicates which nodes are processed.
1.43
1.44 ///The type of the map that indicates which nodes are processed.
1.45 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
1.46 + ///By default it is a NullMap.
1.47 typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
1.48 ///Instantiates a \ref ProcessedMap.
1.49
1.50 @@ -895,21 +893,22 @@
1.51
1.52 ///The type of the map that stores the distances of the nodes.
1.53 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
1.54 - ///
1.55 - typedef NullMap<typename Digraph::Node,int> DistMap;
1.56 + typedef typename Digraph::template NodeMap<int> DistMap;
1.57 ///Instantiates a \ref DistMap.
1.58
1.59 ///This function instantiates a \ref DistMap.
1.60 ///\param g is the digraph, to which we would like to define
1.61 ///the \ref DistMap
1.62 -#ifdef DOXYGEN
1.63 static DistMap *createDistMap(const Digraph &g)
1.64 -#else
1.65 - static DistMap *createDistMap(const Digraph &)
1.66 -#endif
1.67 {
1.68 - return new DistMap();
1.69 + return new DistMap(g);
1.70 }
1.71 +
1.72 + ///The type of the shortest paths.
1.73 +
1.74 + ///The type of the shortest paths.
1.75 + ///It must meet the \ref concepts::Path "Path" concept.
1.76 + typedef lemon::Path<Digraph> Path;
1.77 };
1.78
1.79 /// Default traits class used by \ref BfsWizard
1.80 @@ -939,51 +938,39 @@
1.81 void *_pred;
1.82 //Pointer to the map of distances.
1.83 void *_dist;
1.84 - //Pointer to the source node.
1.85 - Node _source;
1.86 + //Pointer to the shortest path to the target node.
1.87 + void *_path;
1.88 + //Pointer to the distance of the target node.
1.89 + int *_di;
1.90
1.91 public:
1.92 /// Constructor.
1.93
1.94 /// This constructor does not require parameters, therefore it initiates
1.95 - /// all of the attributes to default values (0, INVALID).
1.96 + /// all of the attributes to \c 0.
1.97 BfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0),
1.98 - _dist(0), _source(INVALID) {}
1.99 + _dist(0), _path(0), _di(0) {}
1.100
1.101 /// Constructor.
1.102
1.103 - /// This constructor requires some parameters,
1.104 - /// listed in the parameters list.
1.105 - /// Others are initiated to 0.
1.106 + /// This constructor requires one parameter,
1.107 + /// others are initiated to \c 0.
1.108 /// \param g The digraph the algorithm runs on.
1.109 - /// \param s The source node.
1.110 - BfsWizardBase(const GR &g, Node s=INVALID) :
1.111 + BfsWizardBase(const GR &g) :
1.112 _g(reinterpret_cast<void*>(const_cast<GR*>(&g))),
1.113 - _reached(0), _processed(0), _pred(0), _dist(0), _source(s) {}
1.114 + _reached(0), _processed(0), _pred(0), _dist(0), _path(0), _di(0) {}
1.115
1.116 };
1.117
1.118 - /// Auxiliary class for the function type interface of BFS algorithm.
1.119 + /// Auxiliary class for the function-type interface of BFS algorithm.
1.120
1.121 - /// This auxiliary class is created to implement the function type
1.122 - /// interface of \ref Bfs algorithm. It uses the functions and features
1.123 - /// of the plain \ref Bfs, but it is much simpler to use it.
1.124 - /// It should only be used through the \ref bfs() function, which makes
1.125 - /// it easier to use the algorithm.
1.126 + /// This auxiliary class is created to implement the
1.127 + /// \ref bfs() "function-type interface" of \ref Bfs algorithm.
1.128 + /// It does not have own \ref run() method, it uses the functions
1.129 + /// and features of the plain \ref Bfs.
1.130 ///
1.131 - /// Simplicity means that the way to change the types defined
1.132 - /// in the traits class is based on functions that returns the new class
1.133 - /// and not on templatable built-in classes.
1.134 - /// When using the plain \ref Bfs
1.135 - /// the new class with the modified type comes from
1.136 - /// the original class by using the ::
1.137 - /// operator. In the case of \ref BfsWizard only
1.138 - /// a function have to be called, and it will
1.139 - /// return the needed class.
1.140 - ///
1.141 - /// It does not have own \ref run() method. When its \ref run() method
1.142 - /// is called, it initiates a plain \ref Bfs object, and calls the
1.143 - /// \ref Bfs::run() method of it.
1.144 + /// This class should only be used through the \ref bfs() function,
1.145 + /// which makes it easier to use the algorithm.
1.146 template<class TR>
1.147 class BfsWizard : public TR
1.148 {
1.149 @@ -1006,6 +993,8 @@
1.150 typedef typename TR::ReachedMap ReachedMap;
1.151 ///\brief The type of the map that indicates which nodes are processed.
1.152 typedef typename TR::ProcessedMap ProcessedMap;
1.153 + ///The type of the shortest paths
1.154 + typedef typename TR::Path Path;
1.155
1.156 public:
1.157
1.158 @@ -1016,51 +1005,70 @@
1.159
1.160 /// Constructor that requires parameters.
1.161 /// These parameters will be the default values for the traits class.
1.162 - BfsWizard(const Digraph &g, Node s=INVALID) :
1.163 - TR(g,s) {}
1.164 + /// \param g The digraph the algorithm runs on.
1.165 + BfsWizard(const Digraph &g) :
1.166 + TR(g) {}
1.167
1.168 ///Copy constructor
1.169 BfsWizard(const TR &b) : TR(b) {}
1.170
1.171 ~BfsWizard() {}
1.172
1.173 - ///Runs BFS algorithm from a source node.
1.174 + ///Runs BFS algorithm from the given source node.
1.175
1.176 - ///Runs BFS algorithm from a source node.
1.177 - ///The node can be given with the \ref source() function.
1.178 + ///This method runs BFS algorithm from node \c s
1.179 + ///in order to compute the shortest path to each node.
1.180 + void run(Node s)
1.181 + {
1.182 + Bfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g));
1.183 + if (Base::_pred)
1.184 + alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
1.185 + if (Base::_dist)
1.186 + alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
1.187 + if (Base::_reached)
1.188 + alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached));
1.189 + if (Base::_processed)
1.190 + alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
1.191 + if (s!=INVALID)
1.192 + alg.run(s);
1.193 + else
1.194 + alg.run();
1.195 + }
1.196 +
1.197 + ///Finds the shortest path between \c s and \c t.
1.198 +
1.199 + ///This method runs BFS algorithm from node \c s
1.200 + ///in order to compute the shortest path to node \c t
1.201 + ///(it stops searching when \c t is processed).
1.202 + ///
1.203 + ///\return \c true if \c t is reachable form \c s.
1.204 + bool run(Node s, Node t)
1.205 + {
1.206 + if (s==INVALID || t==INVALID) throw UninitializedParameter();
1.207 + Bfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g));
1.208 + if (Base::_pred)
1.209 + alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
1.210 + if (Base::_dist)
1.211 + alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
1.212 + if (Base::_reached)
1.213 + alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached));
1.214 + if (Base::_processed)
1.215 + alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
1.216 + alg.run(s,t);
1.217 + if (Base::_path)
1.218 + *reinterpret_cast<Path*>(Base::_path) = alg.path(t);
1.219 + if (Base::_di)
1.220 + *Base::_di = alg.dist(t);
1.221 + return alg.reached(t);
1.222 + }
1.223 +
1.224 + ///Runs BFS algorithm to visit all nodes in the digraph.
1.225 +
1.226 + ///This method runs BFS algorithm in order to compute
1.227 + ///the shortest path to each node.
1.228 void run()
1.229 {
1.230 - if(Base::_source==INVALID) throw UninitializedParameter();
1.231 - Bfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g));
1.232 - if(Base::_reached)
1.233 - alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached));
1.234 - if(Base::_processed)
1.235 - alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
1.236 - if(Base::_pred)
1.237 - alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
1.238 - if(Base::_dist)
1.239 - alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
1.240 - alg.run(Base::_source);
1.241 - }
1.242 -
1.243 - ///Runs BFS algorithm from the given node.
1.244 -
1.245 - ///Runs BFS algorithm from the given node.
1.246 - ///\param s is the given source.
1.247 - void run(Node s)
1.248 - {
1.249 - Base::_source=s;
1.250 - run();
1.251 - }
1.252 -
1.253 - /// Sets the source node, from which the Bfs algorithm runs.
1.254 -
1.255 - /// Sets the source node, from which the Bfs algorithm runs.
1.256 - /// \param s is the source node.
1.257 - BfsWizard<TR> &source(Node s)
1.258 - {
1.259 - Base::_source=s;
1.260 - return *this;
1.261 + run(INVALID);
1.262 }
1.263
1.264 template<class T>
1.265 @@ -1069,10 +1077,10 @@
1.266 static PredMap *createPredMap(const Digraph &) { return 0; };
1.267 SetPredMapBase(const TR &b) : TR(b) {}
1.268 };
1.269 - ///\brief \ref named-templ-param "Named parameter"
1.270 + ///\brief \ref named-func-param "Named parameter"
1.271 ///for setting \ref PredMap object.
1.272 ///
1.273 - /// \ref named-templ-param "Named parameter"
1.274 + ///\ref named-func-param "Named parameter"
1.275 ///for setting \ref PredMap object.
1.276 template<class T>
1.277 BfsWizard<SetPredMapBase<T> > predMap(const T &t)
1.278 @@ -1087,10 +1095,10 @@
1.279 static ReachedMap *createReachedMap(const Digraph &) { return 0; };
1.280 SetReachedMapBase(const TR &b) : TR(b) {}
1.281 };
1.282 - ///\brief \ref named-templ-param "Named parameter"
1.283 + ///\brief \ref named-func-param "Named parameter"
1.284 ///for setting \ref ReachedMap object.
1.285 ///
1.286 - /// \ref named-templ-param "Named parameter"
1.287 + /// \ref named-func-param "Named parameter"
1.288 ///for setting \ref ReachedMap object.
1.289 template<class T>
1.290 BfsWizard<SetReachedMapBase<T> > reachedMap(const T &t)
1.291 @@ -1100,15 +1108,33 @@
1.292 }
1.293
1.294 template<class T>
1.295 + struct SetDistMapBase : public Base {
1.296 + typedef T DistMap;
1.297 + static DistMap *createDistMap(const Digraph &) { return 0; };
1.298 + SetDistMapBase(const TR &b) : TR(b) {}
1.299 + };
1.300 + ///\brief \ref named-func-param "Named parameter"
1.301 + ///for setting \ref DistMap object.
1.302 + ///
1.303 + /// \ref named-func-param "Named parameter"
1.304 + ///for setting \ref DistMap object.
1.305 + template<class T>
1.306 + BfsWizard<SetDistMapBase<T> > distMap(const T &t)
1.307 + {
1.308 + Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t));
1.309 + return BfsWizard<SetDistMapBase<T> >(*this);
1.310 + }
1.311 +
1.312 + template<class T>
1.313 struct SetProcessedMapBase : public Base {
1.314 typedef T ProcessedMap;
1.315 static ProcessedMap *createProcessedMap(const Digraph &) { return 0; };
1.316 SetProcessedMapBase(const TR &b) : TR(b) {}
1.317 };
1.318 - ///\brief \ref named-templ-param "Named parameter"
1.319 + ///\brief \ref named-func-param "Named parameter"
1.320 ///for setting \ref ProcessedMap object.
1.321 ///
1.322 - /// \ref named-templ-param "Named parameter"
1.323 + /// \ref named-func-param "Named parameter"
1.324 ///for setting \ref ProcessedMap object.
1.325 template<class T>
1.326 BfsWizard<SetProcessedMapBase<T> > processedMap(const T &t)
1.327 @@ -1118,37 +1144,49 @@
1.328 }
1.329
1.330 template<class T>
1.331 - struct SetDistMapBase : public Base {
1.332 - typedef T DistMap;
1.333 - static DistMap *createDistMap(const Digraph &) { return 0; };
1.334 - SetDistMapBase(const TR &b) : TR(b) {}
1.335 + struct SetPathBase : public Base {
1.336 + typedef T Path;
1.337 + SetPathBase(const TR &b) : TR(b) {}
1.338 };
1.339 - ///\brief \ref named-templ-param "Named parameter"
1.340 - ///for setting \ref DistMap object.
1.341 + ///\brief \ref named-func-param "Named parameter"
1.342 + ///for getting the shortest path to the target node.
1.343 ///
1.344 - /// \ref named-templ-param "Named parameter"
1.345 - ///for setting \ref DistMap object.
1.346 + ///\ref named-func-param "Named parameter"
1.347 + ///for getting the shortest path to the target node.
1.348 template<class T>
1.349 - BfsWizard<SetDistMapBase<T> > distMap(const T &t)
1.350 + BfsWizard<SetPathBase<T> > path(const T &t)
1.351 {
1.352 - Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t));
1.353 - return BfsWizard<SetDistMapBase<T> >(*this);
1.354 + Base::_path=reinterpret_cast<void*>(const_cast<T*>(&t));
1.355 + return BfsWizard<SetPathBase<T> >(*this);
1.356 + }
1.357 +
1.358 + ///\brief \ref named-func-param "Named parameter"
1.359 + ///for getting the distance of the target node.
1.360 + ///
1.361 + ///\ref named-func-param "Named parameter"
1.362 + ///for getting the distance of the target node.
1.363 + BfsWizard dist(const int &d)
1.364 + {
1.365 + Base::_di=const_cast<int*>(&d);
1.366 + return *this;
1.367 }
1.368
1.369 };
1.370
1.371 - ///Function type interface for Bfs algorithm.
1.372 + ///Function-type interface for BFS algorithm.
1.373
1.374 /// \ingroup search
1.375 - ///Function type interface for Bfs algorithm.
1.376 + ///Function-type interface for BFS algorithm.
1.377 ///
1.378 - ///This function also has several
1.379 - ///\ref named-templ-func-param "named parameters",
1.380 + ///This function also has several \ref named-func-param "named parameters",
1.381 ///they are declared as the members of class \ref BfsWizard.
1.382 - ///The following
1.383 - ///example shows how to use these parameters.
1.384 + ///The following examples show how to use these parameters.
1.385 ///\code
1.386 - /// bfs(g,source).predMap(preds).run();
1.387 + /// // Compute shortest path from node s to each node
1.388 + /// bfs(g).predMap(preds).distMap(dists).run(s);
1.389 + ///
1.390 + /// // Compute shortest path from s to t
1.391 + /// bool reached = bfs(g).path(p).dist(d).run(s,t);
1.392 ///\endcode
1.393 ///\warning Don't forget to put the \ref BfsWizard::run() "run()"
1.394 ///to the end of the parameter list.
1.395 @@ -1156,9 +1194,9 @@
1.396 ///\sa Bfs
1.397 template<class GR>
1.398 BfsWizard<BfsWizardBase<GR> >
1.399 - bfs(const GR &g,typename GR::Node s=INVALID)
1.400 + bfs(const GR &digraph)
1.401 {
1.402 - return BfsWizard<BfsWizardBase<GR> >(g,s);
1.403 + return BfsWizard<BfsWizardBase<GR> >(digraph);
1.404 }
1.405
1.406 #ifdef DOXYGEN