Changeset 244:c30731a37f91 in lemon for lemon/bfs.h
 Timestamp:
 08/03/08 13:34:57 (12 years ago)
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 default
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 public
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lemon/bfs.h
r210 r244 22 22 ///\ingroup search 23 23 ///\file 24 ///\brief B fsalgorithm.24 ///\brief BFS algorithm. 25 25 26 26 #include <lemon/list_graph.h> … … 33 33 namespace lemon { 34 34 35 36 37 35 ///Default traits class of Bfs class. 38 36 … … 42 40 struct BfsDefaultTraits 43 41 { 44 ///The digraph typethe algorithm runs on.42 ///The type of the digraph the algorithm runs on. 45 43 typedef GR Digraph; 46 ///\brief The type of the map that stores the last 44 45 ///\brief The type of the map that stores the predecessor 47 46 ///arcs of the shortest paths. 48 47 /// 49 ///The type of the map that stores the last48 ///The type of the map that stores the predecessor 50 49 ///arcs of the shortest paths. 51 50 ///It must meet the \ref concepts::WriteMap "WriteMap" concept. 52 /// 53 typedef typename Digraph::template NodeMap<typename GR::Arc> PredMap; 54 ///Instantiates a PredMap. 51 typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap; 52 ///Instantiates a \ref PredMap. 55 53 56 54 ///This function instantiates a \ref PredMap. 57 ///\param G is the digraph, to which we would like to define the PredMap. 55 ///\param g is the digraph, to which we would like to define the 56 ///\ref PredMap. 58 57 ///\todo The digraph alone may be insufficient to initialize 59 static PredMap *createPredMap(const GR &G) 60 { 61 return new PredMap(G); 62 } 58 static PredMap *createPredMap(const Digraph &g) 59 { 60 return new PredMap(g); 61 } 62 63 63 ///The type of the map that indicates which nodes are processed. 64 64 65 65 ///The type of the map that indicates which nodes are processed. 66 66 ///It must meet the \ref concepts::WriteMap "WriteMap" concept. 67 /// \todo named parameter to set this type, function to read and write.67 ///By default it is a NullMap. 68 68 typedef NullMap<typename Digraph::Node,bool> ProcessedMap; 69 ///Instantiates a ProcessedMap.69 ///Instantiates a \ref ProcessedMap. 70 70 71 71 ///This function instantiates a \ref ProcessedMap. … … 73 73 ///we would like to define the \ref ProcessedMap 74 74 #ifdef DOXYGEN 75 static ProcessedMap *createProcessedMap(const GR&g)75 static ProcessedMap *createProcessedMap(const Digraph &g) 76 76 #else 77 static ProcessedMap *createProcessedMap(const GR&)77 static ProcessedMap *createProcessedMap(const Digraph &) 78 78 #endif 79 79 { 80 80 return new ProcessedMap(); 81 81 } 82 82 83 ///The type of the map that indicates which nodes are reached. 83 84 84 85 ///The type of the map that indicates which nodes are reached. 86 ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept. 87 typedef typename Digraph::template NodeMap<bool> ReachedMap; 88 ///Instantiates a \ref ReachedMap. 89 90 ///This function instantiates a \ref ReachedMap. 91 ///\param g is the digraph, to which 92 ///we would like to define the \ref ReachedMap. 93 static ReachedMap *createReachedMap(const Digraph &g) 94 { 95 return new ReachedMap(g); 96 } 97 98 ///The type of the map that stores the distances of the nodes. 99 100 ///The type of the map that stores the distances of the nodes. 85 101 ///It must meet the \ref concepts::WriteMap "WriteMap" concept. 86 ///\todo named parameter to set this type, function to read and write.87 typedef typename Digraph::template NodeMap<bool> ReachedMap;88 ///Instantiates a ReachedMap.89 90 ///This function instantiates a \ref ReachedMap.91 ///\param G is the digraph, to which92 ///we would like to define the \ref ReachedMap.93 static ReachedMap *createReachedMap(const GR &G)94 {95 return new ReachedMap(G);96 }97 ///The type of the map that stores the dists of the nodes.98 99 ///The type of the map that stores the dists of the nodes.100 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.101 ///102 102 typedef typename Digraph::template NodeMap<int> DistMap; 103 ///Instantiates a DistMap.103 ///Instantiates a \ref DistMap. 104 104 105 105 ///This function instantiates a \ref DistMap. 106 ///\param G is the digraph, to which we would like to define107 /// the \ref DistMap108 static DistMap *createDistMap(const GR &G)109 { 110 return new DistMap( G);106 ///\param g is the digraph, to which we would like to define the 107 ///\ref DistMap. 108 static DistMap *createDistMap(const Digraph &g) 109 { 110 return new DistMap(g); 111 111 } 112 112 }; … … 117 117 ///This class provides an efficient implementation of the %BFS algorithm. 118 118 /// 119 ///\tparam GR The digraph type the algorithm runs on. The default value is 120 ///\ref ListDigraph. The value of GR is not used directly by Bfs, it 121 ///is only passed to \ref BfsDefaultTraits. 119 ///There is also a \ref bfs() "function type interface" for the BFS 120 ///algorithm, which is convenient in the simplier cases and it can be 121 ///used easier. 122 /// 123 ///\tparam GR The type of the digraph the algorithm runs on. 124 ///The default value is \ref ListDigraph. The value of GR is not used 125 ///directly by \ref Bfs, it is only passed to \ref BfsDefaultTraits. 122 126 ///\tparam TR Traits class to set various data types used by the algorithm. 123 127 ///The default traits class is … … 125 129 ///See \ref BfsDefaultTraits for the documentation of 126 130 ///a Bfs traits class. 127 128 131 #ifdef DOXYGEN 129 132 template <typename GR, … … 135 138 class Bfs { 136 139 public: 137 /** 138 * \brief \ref Exception for uninitialized parameters. 139 * 140 * This error represents problems in the initialization 141 * of the parameters of the algorithms. 142 */ 140 ///\ref Exception for uninitialized parameters. 141 142 ///This error represents problems in the initialization of the 143 ///parameters of the algorithm. 143 144 class UninitializedParameter : public lemon::UninitializedParameter { 144 145 public: … … 148 149 }; 149 150 151 ///The type of the digraph the algorithm runs on. 152 typedef typename TR::Digraph Digraph; 153 154 ///\brief The type of the map that stores the predecessor arcs of the 155 ///shortest paths. 156 typedef typename TR::PredMap PredMap; 157 ///The type of the map that stores the distances of the nodes. 158 typedef typename TR::DistMap DistMap; 159 ///The type of the map that indicates which nodes are reached. 160 typedef typename TR::ReachedMap ReachedMap; 161 ///The type of the map that indicates which nodes are processed. 162 typedef typename TR::ProcessedMap ProcessedMap; 163 ///The type of the paths. 164 typedef PredMapPath<Digraph, PredMap> Path; 165 166 ///The traits class. 150 167 typedef TR Traits; 151 ///The type of the underlying digraph. 152 typedef typename TR::Digraph Digraph; 153 154 ///\brief The type of the map that stores the last 155 ///arcs of the shortest paths. 156 typedef typename TR::PredMap PredMap; 157 ///The type of the map indicating which nodes are reached. 158 typedef typename TR::ReachedMap ReachedMap; 159 ///The type of the map indicating which nodes are processed. 160 typedef typename TR::ProcessedMap ProcessedMap; 161 ///The type of the map that stores the dists of the nodes. 162 typedef typename TR::DistMap DistMap; 168 163 169 private: 164 170 … … 168 174 typedef typename Digraph::OutArcIt OutArcIt; 169 175 170 // /Pointer to the underlying digraph.176 //Pointer to the underlying digraph. 171 177 const Digraph *G; 172 // /Pointer to the map of predecessorsarcs.178 //Pointer to the map of predecessor arcs. 173 179 PredMap *_pred; 174 // /Indicates if \ref _pred is locally allocated (\ctrue) or not.180 //Indicates if _pred is locally allocated (true) or not. 175 181 bool local_pred; 176 // /Pointer to the map of distances.182 //Pointer to the map of distances. 177 183 DistMap *_dist; 178 // /Indicates if \ref _dist is locally allocated (\ctrue) or not.184 //Indicates if _dist is locally allocated (true) or not. 179 185 bool local_dist; 180 // /Pointer to the map of reached status of the nodes.186 //Pointer to the map of reached status of the nodes. 181 187 ReachedMap *_reached; 182 // /Indicates if \ref _reached is locally allocated (\ctrue) or not.188 //Indicates if _reached is locally allocated (true) or not. 183 189 bool local_reached; 184 // /Pointer to the map of processed status of the nodes.190 //Pointer to the map of processed status of the nodes. 185 191 ProcessedMap *_processed; 186 // /Indicates if \ref _processed is locally allocated (\ctrue) or not.192 //Indicates if _processed is locally allocated (true) or not. 187 193 bool local_processed; 188 194 … … 192 198 193 199 ///Creates the maps if necessary. 194 195 200 ///\todo Better memory allocation (instead of new). 196 201 void create_maps() … … 235 240 }; 236 241 ///\brief \ref namedtemplparam "Named parameter" for setting 237 /// PredMap type238 /// 239 ///\ref namedtemplparam "Named parameter" for setting PredMap type240 /// 242 ///\ref PredMap type. 243 /// 244 ///\ref namedtemplparam "Named parameter" for setting 245 ///\ref PredMap type. 241 246 template <class T> 242 247 struct DefPredMap : public Bfs< Digraph, DefPredMapTraits<T> > { … … 253 258 }; 254 259 ///\brief \ref namedtemplparam "Named parameter" for setting 255 /// DistMap type256 /// 257 ///\ref namedtemplparam "Named parameter" for setting DistMap type258 /// 260 ///\ref DistMap type. 261 /// 262 ///\ref namedtemplparam "Named parameter" for setting 263 ///\ref DistMap type. 259 264 template <class T> 260 265 struct DefDistMap : public Bfs< Digraph, DefDistMapTraits<T> > { … … 271 276 }; 272 277 ///\brief \ref namedtemplparam "Named parameter" for setting 273 /// ReachedMap type274 /// 275 ///\ref namedtemplparam "Named parameter" for setting ReachedMap type276 /// 278 ///\ref ReachedMap type. 279 /// 280 ///\ref namedtemplparam "Named parameter" for setting 281 ///\ref ReachedMap type. 277 282 template <class T> 278 283 struct DefReachedMap : public Bfs< Digraph, DefReachedMapTraits<T> > { … … 289 294 }; 290 295 ///\brief \ref namedtemplparam "Named parameter" for setting 291 /// ProcessedMap type292 /// 293 ///\ref namedtemplparam "Named parameter" for setting ProcessedMap type294 /// 296 ///\ref ProcessedMap type. 297 /// 298 ///\ref namedtemplparam "Named parameter" for setting 299 ///\ref ProcessedMap type. 295 300 template <class T> 296 301 struct DefProcessedMap : public Bfs< Digraph, DefProcessedMapTraits<T> > { … … 300 305 struct DefDigraphProcessedMapTraits : public Traits { 301 306 typedef typename Digraph::template NodeMap<bool> ProcessedMap; 302 static ProcessedMap *createProcessedMap(const Digraph & G)307 static ProcessedMap *createProcessedMap(const Digraph &g) 303 308 { 304 return new ProcessedMap( G);305 } 306 }; 307 ///\brief \ref namedtemplparam "Named parameter" 308 /// for setting the ProcessedMap type to be Digraph::NodeMap<bool>.309 /// 310 ///\ref namedtemplparam "Named parameter" 311 /// for setting the ProcessedMap type to be Digraph::NodeMap<bool>.309 return new ProcessedMap(g); 310 } 311 }; 312 ///\brief \ref namedtemplparam "Named parameter" for setting 313 ///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>. 314 /// 315 ///\ref namedtemplparam "Named parameter" for setting 316 ///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>. 312 317 ///If you don't set it explicitly, it will be automatically allocated. 313 318 template <class T> … … 323 328 ///Constructor. 324 329 325 /// \param _G the digraph the algorithm will run on.326 /// 327 Bfs(const Digraph & _G) :328 G(& _G),330 ///Constructor. 331 ///\param g The digraph the algorithm runs on. 332 Bfs(const Digraph &g) : 333 G(&g), 329 334 _pred(NULL), local_pred(false), 330 335 _dist(NULL), local_dist(false), … … 342 347 } 343 348 344 ///Sets the map storingthe predecessor arcs.345 346 ///Sets the map storingthe predecessor arcs.349 ///Sets the map that stores the predecessor arcs. 350 351 ///Sets the map that stores the predecessor arcs. 347 352 ///If you don't use this function before calling \ref run(), 348 353 ///it will allocate one. The destructor deallocates this … … 359 364 } 360 365 361 ///Sets the map indicating the reached nodes.362 363 ///Sets the map indicating the reached nodes.366 ///Sets the map that indicates which nodes are reached. 367 368 ///Sets the map that indicates which nodes are reached. 364 369 ///If you don't use this function before calling \ref run(), 365 370 ///it will allocate one. The destructor deallocates this … … 376 381 } 377 382 378 ///Sets the map indicating the processed nodes.379 380 ///Sets the map indicating the processed nodes.383 ///Sets the map that indicates which nodes are processed. 384 385 ///Sets the map that indicates which nodes are processed. 381 386 ///If you don't use this function before calling \ref run(), 382 387 ///it will allocate one. The destructor deallocates this … … 393 398 } 394 399 395 ///Sets the map storing the distances calculated by the algorithm. 396 397 ///Sets the map storing the distances calculated by the algorithm. 400 ///Sets the map that stores the distances of the nodes. 401 402 ///Sets the map that stores the distances of the nodes calculated by 403 ///the algorithm. 398 404 ///If you don't use this function before calling \ref run(), 399 405 ///it will allocate one. The destructor deallocates this … … 411 417 412 418 public: 419 413 420 ///\name Execution control 414 421 ///The simplest way to execute the algorithm is to use 415 ///one of the member functions called \ c run(...).422 ///one of the member functions called \ref lemon::Bfs::run() "run()". 416 423 ///\n 417 ///If you need more control on the execution, 418 /// first you must call \ref init(), then you can add several source nodes419 /// with \ref addSource().420 ///Finally \ref start() will perform the actual path421 /// computation.424 ///If you need more control on the execution, first you must call 425 ///\ref lemon::Bfs::init() "init()", then you can add several source 426 ///nodes with \ref lemon::Bfs::addSource() "addSource()". 427 ///Finally \ref lemon::Bfs::start() "start()" will perform the 428 ///actual path computation. 422 429 423 430 ///@{ 424 431 425 /// \briefInitializes the internal data structures.426 /// 432 ///Initializes the internal data structures. 433 427 434 ///Initializes the internal data structures. 428 435 /// … … 462 469 ///\return The processed node. 463 470 /// 464 ///\ warning The queue must not be empty!471 ///\pre The queue must not be empty. 465 472 Node processNextNode() 466 473 { … … 484 491 ///Processes the next node. 485 492 486 ///Processes the next node . And checks thatthe given target node493 ///Processes the next node and checks if the given target node 487 494 ///is reached. If the target node is reachable from the processed 488 ///node then the reached parameter will be set true. The reached 489 ///parameter should be initially false. 495 ///node, then the \c reach parameter will be set to \c true. 490 496 /// 491 497 ///\param target The target node. 492 ///\retval reach Indicates that the target node is reached. 498 ///\retval reach Indicates if the target node is reached. 499 ///It should be initially \c false. 500 /// 493 501 ///\return The processed node. 494 502 /// 495 ///\ warning The queue must not be empty!503 ///\pre The queue must not be empty. 496 504 Node processNextNode(Node target, bool& reach) 497 505 { … … 516 524 ///Processes the next node. 517 525 518 ///Processes the next node. And checks that at least one of 519 ///reached node has true value in the \c nm node map. If one node 520 ///with true value is reachable from the processed node then the 521 ///rnode parameter will be set to the first of such nodes. 522 /// 523 ///\param nm The node map of possible targets. 526 ///Processes the next node and checks if at least one of reached 527 ///nodes has \c true value in the \c nm node map. If one node 528 ///with \c true value is reachable from the processed node, then the 529 ///\c rnode parameter will be set to the first of such nodes. 530 /// 531 ///\param nm A \c bool (or convertible) node map that indicates the 532 ///possible targets. 524 533 ///\retval rnode The reached target node. 534 ///It should be initially \c INVALID. 535 /// 525 536 ///\return The processed node. 526 537 /// 527 ///\ warning The queue must not be empty!538 ///\pre The queue must not be empty. 528 539 template<class NM> 529 540 Node processNextNode(const NM& nm, Node& rnode) … … 547 558 } 548 559 549 ///Next node to be processed. 550 551 ///Next node to be processed. 552 /// 553 ///\return The next node to be processed or INVALID if the queue is 554 /// empty. 555 Node nextNode() 560 ///The next node to be processed. 561 562 ///Returns the next node to be processed or \c INVALID if the queue 563 ///is empty. 564 Node nextNode() const 556 565 { 557 566 return _queue_tail<_queue_head?_queue[_queue_tail]:INVALID; … … 559 568 560 569 ///\brief Returns \c false if there are nodes 561 ///to be processed in the queue570 ///to be processed. 562 571 /// 563 572 ///Returns \c false if there are nodes 564 ///to be processed in the queue 565 bool emptyQueue() { return _queue_tail==_queue_head; } 573 ///to be processed in the queue. 574 bool emptyQueue() const { return _queue_tail==_queue_head; } 575 566 576 ///Returns the number of the nodes to be processed. 567 577 568 578 ///Returns the number of the nodes to be processed in the queue. 569 int queueSize() { return _queue_head_queue_tail; }579 int queueSize() const { return _queue_head_queue_tail; } 570 580 571 581 ///Executes the algorithm. … … 573 583 ///Executes the algorithm. 574 584 /// 575 ///\pre init() must be called and at least one node should be added576 ///with addSource() before using this function.577 ///578 585 ///This method runs the %BFS algorithm from the root node(s) 579 ///in order to 580 ///compute the 581 ///shortest path to each node. The algorithm computes 582 /// The shortest path tree. 583 /// The distance of each node from the root(s). 586 ///in order to compute the shortest path to each node. 587 /// 588 ///The algorithm computes 589 /// the shortest path tree (forest), 590 /// the distance of each node from the root(s). 591 /// 592 ///\pre init() must be called and at least one root node should be 593 ///added with addSource() before using this function. 594 /// 595 ///\note <tt>b.start()</tt> is just a shortcut of the following code. 596 ///\code 597 /// while ( !b.emptyQueue() ) { 598 /// b.processNextNode(); 599 /// } 600 ///\endcode 584 601 void start() 585 602 { … … 587 604 } 588 605 589 ///Executes the algorithm until \c dest is reached. 590 591 ///Executes the algorithm until \c dest is reached. 592 /// 593 ///\pre init() must be called and at least one node should be added 594 ///with addSource() before using this function. 606 ///Executes the algorithm until the given target node is reached. 607 608 ///Executes the algorithm until the given target node is reached. 595 609 /// 596 610 ///This method runs the %BFS algorithm from the root node(s) 597 611 ///in order to compute the shortest path to \c dest. 612 /// 598 613 ///The algorithm computes 599 /// The shortest path to \c dest. 600 /// The distance of \c dest from the root(s). 614 /// the shortest path to \c dest, 615 /// the distance of \c dest from the root(s). 616 /// 617 ///\pre init() must be called and at least one root node should be 618 ///added with addSource() before using this function. 619 /// 620 ///\note <tt>b.start(t)</tt> is just a shortcut of the following code. 621 ///\code 622 /// bool reach = false; 623 /// while ( !b.emptyQueue() && !reach ) { 624 /// b.processNextNode(t, reach); 625 /// } 626 ///\endcode 601 627 void start(Node dest) 602 628 { … … 609 635 ///Executes the algorithm until a condition is met. 610 636 /// 611 /// \pre init() must be called and at least one node should be added612 /// with addSource() before using this function.613 /// 614 /// \param nm must be a bool (or convertible) node map. The615 /// algorithm will stop when it reaches a node \c v with616 /// <tt>nm[v]</tt> true.637 ///This method runs the %BFS algorithm from the root node(s) in 638 ///order to compute the shortest path to a node \c v with 639 /// <tt>nm[v]</tt> true, if such a node can be found. 640 /// 641 ///\param nm A \c bool (or convertible) node map. The algorithm 642 ///will stop when it reaches a node \c v with <tt>nm[v]</tt> true. 617 643 /// 618 644 ///\return The reached node \c v with <tt>nm[v]</tt> true or 619 645 ///\c INVALID if no such node was found. 620 template<class NM> 621 Node start(const NM &nm) 646 /// 647 ///\pre init() must be called and at least one root node should be 648 ///added with addSource() before using this function. 649 /// 650 ///\note <tt>b.start(nm)</tt> is just a shortcut of the following code. 651 ///\code 652 /// Node rnode = INVALID; 653 /// while ( !b.emptyQueue() && rnode == INVALID ) { 654 /// b.processNextNode(nm, rnode); 655 /// } 656 /// return rnode; 657 ///\endcode 658 template<class NodeBoolMap> 659 Node start(const NodeBoolMap &nm) 622 660 { 623 661 Node rnode = INVALID; … … 628 666 } 629 667 630 ///Runs %BFS algorithm from node \c s.631 632 ///This method runs the %BFS algorithm from a rootnode \c s633 ///in order to 634 /// compute the635 /// shortest path to each node.The algorithm computes636 /// The shortest path tree.637 /// The distance of each node from the root.638 /// 639 ///\note b.run(s)is just a shortcut of the following code.668 ///Runs the algorithm from the given node. 669 670 ///This method runs the %BFS algorithm from node \c s 671 ///in order to compute the shortest path to each node. 672 /// 673 ///The algorithm computes 674 /// the shortest path tree, 675 /// the distance of each node from the root. 676 /// 677 ///\note <tt>b.run(s)</tt> is just a shortcut of the following code. 640 678 ///\code 641 679 /// b.init(); … … 651 689 ///Finds the shortest path between \c s and \c t. 652 690 653 ///Finds the shortest path between \c s and \c t. 654 /// 655 ///\return The length of the shortest st path if there exists one, 656 ///0 otherwise. 657 ///\note Apart from the return value, b.run(s) is 658 ///just a shortcut of the following code. 691 ///This method runs the %BFS algorithm from node \c s 692 ///in order to compute the shortest path to \c t. 693 /// 694 ///\return The length of the shortest <tt>s</tt><tt>t</tt> path, 695 ///if \c t is reachable form \c s, \c 0 otherwise. 696 /// 697 ///\note Apart from the return value, <tt>b.run(s,t)</tt> is just a 698 ///shortcut of the following code. 659 699 ///\code 660 700 /// b.init(); … … 669 709 } 670 710 711 ///Runs the algorithm to visit all nodes in the digraph. 712 713 ///This method runs the %BFS algorithm in order to 714 ///compute the shortest path to each node. 715 /// 716 ///The algorithm computes 717 /// the shortest path tree (forest), 718 /// the distance of each node from the root(s). 719 /// 720 ///\note <tt>b.run(s)</tt> is just a shortcut of the following code. 721 ///\code 722 /// b.init(); 723 /// for (NodeIt n(gr); n != INVALID; ++n) { 724 /// if (!b.reached(n)) { 725 /// b.addSource(n); 726 /// b.start(); 727 /// } 728 /// } 729 ///\endcode 730 void run() { 731 init(); 732 for (NodeIt n(*G); n != INVALID; ++n) { 733 if (!reached(n)) { 734 addSource(n); 735 start(); 736 } 737 } 738 } 739 671 740 ///@} 672 741 … … 674 743 ///The result of the %BFS algorithm can be obtained using these 675 744 ///functions.\n 676 /// Before the use of these functions,677 /// either run() or start() must be calleb.745 ///Either \ref lemon::Bfs::run() "run()" or \ref lemon::Bfs::start() 746 ///"start()" must be called before using them. 678 747 679 748 ///@{ 680 749 681 typedef PredMapPath<Digraph, PredMap> Path; 682 683 ///Gives back the shortest path. 684 685 ///Gives back the shortest path. 686 ///\pre The \c t should be reachable from the source. 687 Path path(Node t) 688 { 689 return Path(*G, *_pred, t); 690 } 750 ///The shortest path to a node. 751 752 ///Returns the shortest path to a node. 753 /// 754 ///\warning \c t should be reachable from the root(s). 755 /// 756 ///\pre Either \ref run() or \ref start() must be called before 757 ///using this function. 758 Path path(Node t) const { return Path(*G, *_pred, t); } 691 759 692 760 ///The distance of a node from the root(s). 693 761 694 762 ///Returns the distance of a node from the root(s). 695 ///\pre \ref run() must be called before using this function. 696 ///\warning If node \c v in unreachable from the root(s) the return value 697 ///of this function is undefined. 763 /// 764 ///\warning If node \c v is not reachable from the root(s), then 765 ///the return value of this function is undefined. 766 /// 767 ///\pre Either \ref run() or \ref start() must be called before 768 ///using this function. 698 769 int dist(Node v) const { return (*_dist)[v]; } 699 770 700 ///Returns the 'previous arc' of the shortest path tree. 701 702 ///For a node \c v it returns the 'previous arc' 703 ///of the shortest path tree, 704 ///i.e. it returns the last arc of a shortest path from the root(s) to \c 705 ///v. It is \ref INVALID 706 ///if \c v is unreachable from the root(s) or \c v is a root. The 707 ///shortest path tree used here is equal to the shortest path tree used in 708 ///\ref predNode(). 709 ///\pre Either \ref run() or \ref start() must be called before using 710 ///this function. 771 ///Returns the 'previous arc' of the shortest path tree for a node. 772 773 ///This function returns the 'previous arc' of the shortest path 774 ///tree for the node \c v, i.e. it returns the last arc of a 775 ///shortest path from the root(s) to \c v. It is \c INVALID if \c v 776 ///is not reachable from the root(s) or if \c v is a root. 777 /// 778 ///The shortest path tree used here is equal to the shortest path 779 ///tree used in \ref predNode(). 780 /// 781 ///\pre Either \ref run() or \ref start() must be called before 782 ///using this function. 711 783 Arc predArc(Node v) const { return (*_pred)[v];} 712 784 713 ///Returns the 'previous node' of the shortest path tree. 714 715 ///For a node \c v it returns the 'previous node' 716 ///of the shortest path tree, 717 ///i.e. it returns the last but one node from a shortest path from the 718 ///root(a) to \c /v. 719 ///It is INVALID if \c v is unreachable from the root(s) or 720 ///if \c v itself a root. 785 ///Returns the 'previous node' of the shortest path tree for a node. 786 787 ///This function returns the 'previous node' of the shortest path 788 ///tree for the node \c v, i.e. it returns the last but one node 789 ///from a shortest path from the root(s) to \c v. It is \c INVALID 790 ///if \c v is not reachable from the root(s) or if \c v is a root. 791 /// 721 792 ///The shortest path tree used here is equal to the shortest path 722 793 ///tree used in \ref predArc(). 794 /// 723 795 ///\pre Either \ref run() or \ref start() must be called before 724 796 ///using this function. … … 726 798 G>source((*_pred)[v]); } 727 799 728 ///Returns a reference to the NodeMap of distances. 729 730 ///Returns a reference to the NodeMap of distances. 731 ///\pre Either \ref run() or \ref init() must 732 ///be called before using this function. 800 ///\brief Returns a const reference to the node map that stores the 801 /// distances of the nodes. 802 /// 803 ///Returns a const reference to the node map that stores the distances 804 ///of the nodes calculated by the algorithm. 805 /// 806 ///\pre Either \ref run() or \ref init() 807 ///must be called before using this function. 733 808 const DistMap &distMap() const { return *_dist;} 734 809 735 ///Returns a reference to the shortest path tree map. 736 737 ///Returns a reference to the NodeMap of the arcs of the 738 ///shortest path tree. 810 ///\brief Returns a const reference to the node map that stores the 811 ///predecessor arcs. 812 /// 813 ///Returns a const reference to the node map that stores the predecessor 814 ///arcs, which form the shortest path tree. 815 /// 739 816 ///\pre Either \ref run() or \ref init() 740 817 ///must be called before using this function. 741 818 const PredMap &predMap() const { return *_pred;} 742 819 743 ///Checks if a node is reachable from the root. 744 745 ///Returns \c true if \c v is reachable from the root. 746 ///\warning The source nodes are indicated as unreached. 820 ///Checks if a node is reachable from the root(s). 821 822 ///Returns \c true if \c v is reachable from the root(s). 747 823 ///\pre Either \ref run() or \ref start() 748 824 ///must be called before using this function. 749 /// 750 bool reached(Node v) { return (*_reached)[v]; } 825 bool reached(Node v) const { return (*_reached)[v]; } 751 826 752 827 ///@} 753 828 }; 754 829 755 ///Default traits class of Bfsfunction.756 757 ///Default traits class of Bfsfunction.830 ///Default traits class of bfs() function. 831 832 ///Default traits class of bfs() function. 758 833 ///\tparam GR Digraph type. 759 834 template<class GR> 760 835 struct BfsWizardDefaultTraits 761 836 { 762 ///The digraph typethe algorithm runs on.837 ///The type of the digraph the algorithm runs on. 763 838 typedef GR Digraph; 764 ///\brief The type of the map that stores the last 839 840 ///\brief The type of the map that stores the predecessor 765 841 ///arcs of the shortest paths. 766 842 /// 767 ///The type of the map that stores the last843 ///The type of the map that stores the predecessor 768 844 ///arcs of the shortest paths. 769 845 ///It must meet the \ref concepts::WriteMap "WriteMap" concept. 770 /// 771 typedef NullMap<typename Digraph::Node,typename GR::Arc> PredMap; 772 ///Instantiates a PredMap. 846 typedef NullMap<typename Digraph::Node,typename Digraph::Arc> PredMap; 847 ///Instantiates a \ref PredMap. 773 848 774 849 ///This function instantiates a \ref PredMap. 775 ///\param g is the digraph, to which we would like to define the PredMap. 850 ///\param g is the digraph, to which we would like to define the 851 ///\ref PredMap. 776 852 ///\todo The digraph alone may be insufficient to initialize 777 853 #ifdef DOXYGEN 778 static PredMap *createPredMap(const GR&g)854 static PredMap *createPredMap(const Digraph &g) 779 855 #else 780 static PredMap *createPredMap(const GR&)856 static PredMap *createPredMap(const Digraph &) 781 857 #endif 782 858 { … … 788 864 ///The type of the map that indicates which nodes are processed. 789 865 ///It must meet the \ref concepts::WriteMap "WriteMap" concept. 790 ///\todo named parameter to set this type, function to read and write.791 866 typedef NullMap<typename Digraph::Node,bool> ProcessedMap; 792 ///Instantiates a ProcessedMap.867 ///Instantiates a \ref ProcessedMap. 793 868 794 869 ///This function instantiates a \ref ProcessedMap. 795 870 ///\param g is the digraph, to which 796 ///we would like to define the \ref ProcessedMap 871 ///we would like to define the \ref ProcessedMap. 797 872 #ifdef DOXYGEN 798 static ProcessedMap *createProcessedMap(const GR&g)873 static ProcessedMap *createProcessedMap(const Digraph &g) 799 874 #else 800 static ProcessedMap *createProcessedMap(const GR&)875 static ProcessedMap *createProcessedMap(const Digraph &) 801 876 #endif 802 877 { 803 878 return new ProcessedMap(); 804 879 } 880 805 881 ///The type of the map that indicates which nodes are reached. 806 882 807 883 ///The type of the map that indicates which nodes are reached. 884 ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept. 885 typedef typename Digraph::template NodeMap<bool> ReachedMap; 886 ///Instantiates a \ref ReachedMap. 887 888 ///This function instantiates a \ref ReachedMap. 889 ///\param g is the digraph, to which 890 ///we would like to define the \ref ReachedMap. 891 static ReachedMap *createReachedMap(const Digraph &g) 892 { 893 return new ReachedMap(g); 894 } 895 896 ///The type of the map that stores the distances of the nodes. 897 898 ///The type of the map that stores the distances of the nodes. 808 899 ///It must meet the \ref concepts::WriteMap "WriteMap" concept. 809 ///\todo named parameter to set this type, function to read and write.810 typedef typename Digraph::template NodeMap<bool> ReachedMap;811 ///Instantiates a ReachedMap.812 813 ///This function instantiates a \ref ReachedMap.814 ///\param G is the digraph, to which815 ///we would like to define the \ref ReachedMap.816 static ReachedMap *createReachedMap(const GR &G)817 {818 return new ReachedMap(G);819 }820 ///The type of the map that stores the dists of the nodes.821 822 ///The type of the map that stores the dists of the nodes.823 ///It must meet the \ref concepts::WriteMap "WriteMap" concept.824 900 /// 825 901 typedef NullMap<typename Digraph::Node,int> DistMap; 826 ///Instantiates a DistMap.902 ///Instantiates a \ref DistMap. 827 903 828 904 ///This function instantiates a \ref DistMap. … … 830 906 ///the \ref DistMap 831 907 #ifdef DOXYGEN 832 static DistMap *createDistMap(const GR&g)908 static DistMap *createDistMap(const Digraph &g) 833 909 #else 834 static DistMap *createDistMap(const GR&)910 static DistMap *createDistMap(const Digraph &) 835 911 #endif 836 912 { … … 839 915 }; 840 916 841 /// Default traits used by \ref BfsWizard917 /// Default traits class used by \ref BfsWizard 842 918 843 919 /// To make it easier to use Bfs algorithm 844 /// we have created a wizard class.920 /// we have created a wizard class. 845 921 /// This \ref BfsWizard class needs default traits, 846 /// as well as the \ref Bfs class.922 /// as well as the \ref Bfs class. 847 923 /// The \ref BfsWizardBase is a class to be the default traits of the 848 924 /// \ref BfsWizard class. … … 853 929 typedef BfsWizardDefaultTraits<GR> Base; 854 930 protected: 855 // / Type of the nodes in the digraph.931 //The type of the nodes in the digraph. 856 932 typedef typename Base::Digraph::Node Node; 857 933 858 // / Pointer to the underlying digraph.934 //Pointer to the digraph the algorithm runs on. 859 935 void *_g; 860 // /Pointer to the map of reached nodes.936 //Pointer to the map of reached nodes. 861 937 void *_reached; 862 // /Pointer to the map of processed nodes.938 //Pointer to the map of processed nodes. 863 939 void *_processed; 864 // /Pointer to the map of predecessors arcs.940 //Pointer to the map of predecessors arcs. 865 941 void *_pred; 866 // /Pointer to the map of distances.942 //Pointer to the map of distances. 867 943 void *_dist; 868 // /Pointer to the source node.944 //Pointer to the source node. 869 945 Node _source; 870 946 … … 875 951 /// all of the attributes to default values (0, INVALID). 876 952 BfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0), 877 953 _dist(0), _source(INVALID) {} 878 954 879 955 /// Constructor. … … 882 958 /// listed in the parameters list. 883 959 /// Others are initiated to 0. 884 /// \param g is the initial value of \ref _g885 /// \param s is the initial value of \ref _source960 /// \param g The digraph the algorithm runs on. 961 /// \param s The source node. 886 962 BfsWizardBase(const GR &g, Node s=INVALID) : 887 963 _g(reinterpret_cast<void*>(const_cast<GR*>(&g))), … … 890 966 }; 891 967 892 /// A class to make the usage of Bfs algorithm easier 893 894 /// This class is created to make it easier to use Bfs algorithm. 895 /// It uses the functions and features of the plain \ref Bfs, 896 /// but it is much simpler to use it. 968 /// Auxiliary class for the function type interface of BFS algorithm. 969 970 /// This auxiliary class is created to implement the function type 971 /// interface of \ref Bfs algorithm. It uses the functions and features 972 /// of the plain \ref Bfs, but it is much simpler to use it. 973 /// It should only be used through the \ref bfs() function, which makes 974 /// it easier to use the algorithm. 897 975 /// 898 976 /// Simplicity means that the way to change the types defined … … 903 981 /// the original class by using the :: 904 982 /// operator. In the case of \ref BfsWizard only 905 /// a function have to be called and it will983 /// a function have to be called, and it will 906 984 /// return the needed class. 907 985 /// 908 /// It does not have own \ref run method. When its \ref run method is called909 /// i t initiates a plain \ref Bfs class, and calls the \ref Bfs::run910 /// method of it.986 /// It does not have own \ref run() method. When its \ref run() method 987 /// is called, it initiates a plain \ref Bfs object, and calls the 988 /// \ref Bfs::run() method of it. 911 989 template<class TR> 912 990 class BfsWizard : public TR … … 914 992 typedef TR Base; 915 993 916 ///The type of the underlying digraph.994 ///The type of the digraph the algorithm runs on. 917 995 typedef typename TR::Digraph Digraph; 918 //\e 996 919 997 typedef typename Digraph::Node Node; 920 //\e921 998 typedef typename Digraph::NodeIt NodeIt; 922 //\e923 999 typedef typename Digraph::Arc Arc; 924 //\e925 1000 typedef typename Digraph::OutArcIt OutArcIt; 926 1001 927 ///\brief The type of the map that stores 928 ///the reached nodes 929 typedef typename TR::ReachedMap ReachedMap; 930 ///\brief The type of the map that stores 931 ///the processed nodes 932 typedef typename TR::ProcessedMap ProcessedMap; 933 ///\brief The type of the map that stores the last 1002 ///\brief The type of the map that stores the predecessor 934 1003 ///arcs of the shortest paths. 935 1004 typedef typename TR::PredMap PredMap; 936 /// The type of the map that stores the dists of the nodes.1005 ///\brief The type of the map that stores the distances of the nodes. 937 1006 typedef typename TR::DistMap DistMap; 1007 ///\brief The type of the map that indicates which nodes are reached. 1008 typedef typename TR::ReachedMap ReachedMap; 1009 ///\brief The type of the map that indicates which nodes are processed. 1010 typedef typename TR::ProcessedMap ProcessedMap; 938 1011 939 1012 public: 1013 940 1014 /// Constructor. 941 1015 BfsWizard() : TR() {} … … 953 1027 ~BfsWizard() {} 954 1028 955 ///Runs B fs algorithm from a givennode.956 957 ///Runs B fs algorithm from a givennode.958 ///The node can be given by the \ref sourcefunction.1029 ///Runs BFS algorithm from a source node. 1030 1031 ///Runs BFS algorithm from a source node. 1032 ///The node can be given with the \ref source() function. 959 1033 void run() 960 1034 { … … 972 1046 } 973 1047 974 ///Runs B fsalgorithm from the given node.975 976 ///Runs B fsalgorithm from the given node.1048 ///Runs BFS algorithm from the given node. 1049 1050 ///Runs BFS algorithm from the given node. 977 1051 ///\param s is the given source. 978 1052 void run(Node s) … … 980 1054 Base::_source=s; 981 1055 run(); 1056 } 1057 1058 /// Sets the source node, from which the Bfs algorithm runs. 1059 1060 /// Sets the source node, from which the Bfs algorithm runs. 1061 /// \param s is the source node. 1062 BfsWizard<TR> &source(Node s) 1063 { 1064 Base::_source=s; 1065 return *this; 982 1066 } 983 1067 … … 988 1072 DefPredMapBase(const TR &b) : TR(b) {} 989 1073 }; 990 991 1074 ///\brief \ref namedtemplparam "Named parameter" 992 ///f unction for setting PredMap1075 ///for setting \ref PredMap object. 993 1076 /// 994 1077 /// \ref namedtemplparam "Named parameter" 995 ///function for setting PredMap 996 /// 1078 ///for setting \ref PredMap object. 997 1079 template<class T> 998 1080 BfsWizard<DefPredMapBase<T> > predMap(const T &t) … … 1001 1083 return BfsWizard<DefPredMapBase<T> >(*this); 1002 1084 } 1003 1004 1085 1005 1086 template<class T> … … 1009 1090 DefReachedMapBase(const TR &b) : TR(b) {} 1010 1091 }; 1011 1012 1092 ///\brief \ref namedtemplparam "Named parameter" 1013 ///f unction for setting ReachedMap1093 ///for setting \ref ReachedMap object. 1014 1094 /// 1015 1095 /// \ref namedtemplparam "Named parameter" 1016 ///function for setting ReachedMap 1017 /// 1096 ///for setting \ref ReachedMap object. 1018 1097 template<class T> 1019 1098 BfsWizard<DefReachedMapBase<T> > reachedMap(const T &t) … … 1022 1101 return BfsWizard<DefReachedMapBase<T> >(*this); 1023 1102 } 1024 1025 1103 1026 1104 template<class T> … … 1030 1108 DefProcessedMapBase(const TR &b) : TR(b) {} 1031 1109 }; 1032 1033 1110 ///\brief \ref namedtemplparam "Named parameter" 1034 ///f unction for setting ProcessedMap1111 ///for setting \ref ProcessedMap object. 1035 1112 /// 1036 1113 /// \ref namedtemplparam "Named parameter" 1037 ///function for setting ProcessedMap 1038 /// 1114 ///for setting \ref ProcessedMap object. 1039 1115 template<class T> 1040 1116 BfsWizard<DefProcessedMapBase<T> > processedMap(const T &t) … … 1043 1119 return BfsWizard<DefProcessedMapBase<T> >(*this); 1044 1120 } 1045 1046 1121 1047 1122 template<class T> … … 1051 1126 DefDistMapBase(const TR &b) : TR(b) {} 1052 1127 }; 1053 1054 1128 ///\brief \ref namedtemplparam "Named parameter" 1055 ///f unction for setting DistMap type1129 ///for setting \ref DistMap object. 1056 1130 /// 1057 1131 /// \ref namedtemplparam "Named parameter" 1058 ///function for setting DistMap type 1059 /// 1132 ///for setting \ref DistMap object. 1060 1133 template<class T> 1061 1134 BfsWizard<DefDistMapBase<T> > distMap(const T &t) … … 1063 1136 Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t)); 1064 1137 return BfsWizard<DefDistMapBase<T> >(*this); 1065 }1066 1067 /// Sets the source node, from which the Bfs algorithm runs.1068 1069 /// Sets the source node, from which the Bfs algorithm runs.1070 /// \param s is the source node.1071 BfsWizard<TR> &source(Node s)1072 {1073 Base::_source=s;1074 return *this;1075 1138 } 1076 1139 … … 1102 1165 1103 1166 #ifdef DOXYGEN 1104 /// \brief Visitor class for bfs.1167 /// \brief Visitor class for BFS. 1105 1168 /// 1106 1169 /// This class defines the interface of the BfsVisit events, and 1107 /// it could be the base of a real Visitor class.1170 /// it could be the base of a real visitor class. 1108 1171 template <typename _Digraph> 1109 1172 struct BfsVisitor { … … 1111 1174 typedef typename Digraph::Arc Arc; 1112 1175 typedef typename Digraph::Node Node; 1113 /// \brief Called when the arc reach a node. 1114 /// 1115 /// It is called when the bfs find an arc which target is not 1116 /// reached yet. 1176 /// \brief Called for the source node(s) of the BFS. 1177 /// 1178 /// This function is called for the source node(s) of the BFS. 1179 void start(const Node& node) {} 1180 /// \brief Called when a node is reached first time. 1181 /// 1182 /// This function is called when a node is reached first time. 1183 void reach(const Node& node) {} 1184 /// \brief Called when a node is processed. 1185 /// 1186 /// This function is called when a node is processed. 1187 void process(const Node& node) {} 1188 /// \brief Called when an arc reaches a new node. 1189 /// 1190 /// This function is called when the BFS finds an arc whose target node 1191 /// is not reached yet. 1117 1192 void discover(const Arc& arc) {} 1118 /// \brief Called when the node reached first time. 1119 /// 1120 /// It is Called when the node reached first time. 1121 void reach(const Node& node) {} 1122 /// \brief Called when the arc examined but target of the arc 1193 /// \brief Called when an arc is examined but its target node is 1123 1194 /// already discovered. 1124 1195 /// 1125 /// It called when the arc examined but the target of the arc1196 /// This function is called when an arc is examined but its target node is 1126 1197 /// already discovered. 1127 1198 void examine(const Arc& arc) {} 1128 /// \brief Called for the source node of the bfs.1129 ///1130 /// It is called for the source node of the bfs.1131 void start(const Node& node) {}1132 /// \brief Called when the node processed.1133 ///1134 /// It is Called when the node processed.1135 void process(const Node& node) {}1136 1199 }; 1137 1200 #else … … 1141 1204 typedef typename Digraph::Arc Arc; 1142 1205 typedef typename Digraph::Node Node; 1206 void start(const Node&) {} 1207 void reach(const Node&) {} 1208 void process(const Node&) {} 1143 1209 void discover(const Arc&) {} 1144 void reach(const Node&) {}1145 1210 void examine(const Arc&) {} 1146 void start(const Node&) {}1147 void process(const Node&) {}1148 1211 1149 1212 template <typename _Visitor> … … 1152 1215 Arc arc; 1153 1216 Node node; 1217 visitor.start(node); 1218 visitor.reach(node); 1219 visitor.process(node); 1154 1220 visitor.discover(arc); 1155 visitor.reach(node);1156 1221 visitor.examine(arc); 1157 visitor.start(node);1158 visitor.process(node);1159 1222 } 1160 1223 _Visitor& visitor; … … 1166 1229 /// 1167 1230 /// Default traits class of BfsVisit class. 1168 /// \tparam _Digraph Digraph type.1231 /// \tparam _Digraph The type of the digraph the algorithm runs on. 1169 1232 template<class _Digraph> 1170 1233 struct BfsVisitDefaultTraits { 1171 1234 1172 /// \brief The digraph typethe algorithm runs on.1235 /// \brief The type of the digraph the algorithm runs on. 1173 1236 typedef _Digraph Digraph; 1174 1237 … … 1176 1239 /// 1177 1240 /// The type of the map that indicates which nodes are reached. 1178 /// It must meet the \ref concepts::WriteMap "WriteMap" concept. 1179 /// \todo named parameter to set this type, function to read and write. 1241 /// It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept. 1180 1242 typedef typename Digraph::template NodeMap<bool> ReachedMap; 1181 1243 1182 /// \brief Instantiates a ReachedMap.1244 /// \brief Instantiates a \ref ReachedMap. 1183 1245 /// 1184 1246 /// This function instantiates a \ref ReachedMap. … … 1193 1255 /// \ingroup search 1194 1256 /// 1195 /// \brief %BFS Visit algorithm class.1257 /// \brief %BFS algorithm class with visitor interface. 1196 1258 /// 1197 1259 /// This class provides an efficient implementation of the %BFS algorithm … … 1200 1262 /// The %BfsVisit class provides an alternative interface to the Bfs 1201 1263 /// class. It works with callback mechanism, the BfsVisit object calls 1202 /// on every bfs event the \c Visitor class member functions.1264 /// the member functions of the \c Visitor class on every BFS event. 1203 1265 /// 1204 /// \tparam _Digraph The digraph typethe algorithm runs on.1266 /// \tparam _Digraph The type of the digraph the algorithm runs on. 1205 1267 /// The default value is 1206 /// \ref ListDigraph. The value of _Digraph is not used directly by Bfs, it1207 /// is only passed to \ref BfsDefaultTraits.1208 /// \tparam _Visitor The Visitor object for the algorithm. The1209 /// \ref BfsVisitor "BfsVisitor<_Digraph>" is an empty Visitorwhich1210 /// does not observe the B fs events. If you want to observe the bfs1211 /// events you should implement your own Visitor class.1268 /// \ref ListDigraph. The value of _Digraph is not used directly by 1269 /// \ref BfsVisit, it is only passed to \ref BfsVisitDefaultTraits. 1270 /// \tparam _Visitor The Visitor type that is used by the algorithm. 1271 /// \ref BfsVisitor "BfsVisitor<_Digraph>" is an empty visitor, which 1272 /// does not observe the BFS events. If you want to observe the BFS 1273 /// events, you should implement your own visitor class. 1212 1274 /// \tparam _Traits Traits class to set various data types used by the 1213 1275 /// algorithm. The default traits class is 1214 1276 /// \ref BfsVisitDefaultTraits "BfsVisitDefaultTraits<_Digraph>". 1215 1277 /// See \ref BfsVisitDefaultTraits for the documentation of 1216 /// a B fsvisit traits class.1278 /// a BFS visit traits class. 1217 1279 #ifdef DOXYGEN 1218 1280 template <typename _Digraph, typename _Visitor, typename _Traits> … … 1228 1290 /// 1229 1291 /// This error represents problems in the initialization 1230 /// of the parameters of the algorithm s.1292 /// of the parameters of the algorithm. 1231 1293 class UninitializedParameter : public lemon::UninitializedParameter { 1232 1294 public: … … 1237 1299 }; 1238 1300 1301 ///The traits class. 1239 1302 typedef _Traits Traits; 1240 1303 1304 ///The type of the digraph the algorithm runs on. 1241 1305 typedef typename Traits::Digraph Digraph; 1242 1306 1307 ///The visitor type used by the algorithm. 1243 1308 typedef _Visitor Visitor; 1244 1309 1245 ///The type of the map indicatingwhich nodes are reached.1310 ///The type of the map that indicates which nodes are reached. 1246 1311 typedef typename Traits::ReachedMap ReachedMap; 1247 1312 … … 1253 1318 typedef typename Digraph::OutArcIt OutArcIt; 1254 1319 1255 // /Pointer to the underlying digraph.1320 //Pointer to the underlying digraph. 1256 1321 const Digraph *_digraph; 1257 // /Pointer to the visitor object.1322 //Pointer to the visitor object. 1258 1323 Visitor *_visitor; 1259 // /Pointer to the map of reached status of the nodes.1324 //Pointer to the map of reached status of the nodes. 1260 1325 ReachedMap *_reached; 1261 // /Indicates if \ref _reached is locally allocated (\ctrue) or not.1326 //Indicates if _reached is locally allocated (true) or not. 1262 1327 bool local_reached; 1263 1328 … … 1265 1330 int _list_front, _list_back; 1266 1331 1267 /// \brief Creates the maps if necessary. 1268 /// 1269 /// Creates the maps if necessary. 1332 ///Creates the maps if necessary. 1333 ///\todo Better memory allocation (instead of new). 1270 1334 void create_maps() { 1271 1335 if(!_reached) { … … 1294 1358 }; 1295 1359 /// \brief \ref namedtemplparam "Named parameter" for setting 1296 /// ReachedMap type 1297 /// 1298 /// \ref namedtemplparam "Named parameter" for setting ReachedMap type 1360 /// ReachedMap type. 1361 /// 1362 /// \ref namedtemplparam "Named parameter" for setting ReachedMap type. 1299 1363 template <class T> 1300 1364 struct DefReachedMap : public BfsVisit< Digraph, Visitor, … … 1310 1374 /// Constructor. 1311 1375 /// 1312 /// \param digraph the digraph the algorithm will run on. 1313 /// \param visitor The visitor of the algorithm. 1314 /// 1376 /// \param digraph The digraph the algorithm runs on. 1377 /// \param visitor The visitor object of the algorithm. 1315 1378 BfsVisit(const Digraph& digraph, Visitor& visitor) 1316 1379 : _digraph(&digraph), _visitor(&visitor), … … 1318 1381 1319 1382 /// \brief Destructor. 1320 ///1321 /// Destructor.1322 1383 ~BfsVisit() { 1323 1384 if(local_reached) delete _reached; 1324 1385 } 1325 1386 1326 /// \brief Sets the map indicating if a node isreached.1327 /// 1328 /// Sets the map indicating if a node isreached.1387 /// \brief Sets the map that indicates which nodes are reached. 1388 /// 1389 /// Sets the map that indicates which nodes are reached. 1329 1390 /// If you don't use this function before calling \ref run(), 1330 /// it will allocate one. The dest uctor deallocates this1391 /// it will allocate one. The destructor deallocates this 1331 1392 /// automatically allocated map, of course. 1332 1393 /// \return <tt> (*this) </tt> … … 1341 1402 1342 1403 public: 1404 1343 1405 /// \name Execution control 1344 1406 /// The simplest way to execute the algorithm is to use 1345 /// one of the member functions called \c run(...). 1407 /// one of the member functions called \ref lemon::BfsVisit::run() 1408 /// "run()". 1346 1409 /// \n 1347 /// If you need more control on the execution, 1348 /// first you must call \ref init(), then you can adda source node1349 /// with \ref addSource().1350 /// Finally \ref start() will perform the actual path1351 /// computation.1410 /// If you need more control on the execution, first you must call 1411 /// \ref lemon::BfsVisit::init() "init()", then you can add several 1412 /// source nodes with \ref lemon::BfsVisit::addSource() "addSource()". 1413 /// Finally \ref lemon::BfsVisit::start() "start()" will perform the 1414 /// actual path computation. 1352 1415 1353 1416 /// @{ 1417 1354 1418 /// \brief Initializes the internal data structures. 1355 1419 /// 1356 1420 /// Initializes the internal data structures. 1357 ///1358 1421 void init() { 1359 1422 create_maps(); … … 1383 1446 /// \return The processed node. 1384 1447 /// 1385 /// \pre The queue must not be empty !1448 /// \pre The queue must not be empty. 1386 1449 Node processNextNode() { 1387 1450 Node n = _list[++_list_front]; … … 1404 1467 /// \brief Processes the next node. 1405 1468 /// 1406 /// Processes the next node . And checks thatthe given target node1469 /// Processes the next node and checks if the given target node 1407 1470 /// is reached. If the target node is reachable from the processed 1408 /// node then the reached parameter will be set true. The reached 1409 /// parameter should be initially false. 1471 /// node, then the \c reach parameter will be set to \c true. 1410 1472 /// 1411 1473 /// \param target The target node. 1412 /// \retval reach Indicates that the target node is reached. 1474 /// \retval reach Indicates if the target node is reached. 1475 /// It should be initially \c false. 1476 /// 1413 1477 /// \return The processed node. 1414 1478 /// 1415 /// \ warning The queue must not be empty!1479 /// \pre The queue must not be empty. 1416 1480 Node processNextNode(Node target, bool& reach) { 1417 1481 Node n = _list[++_list_front]; … … 1435 1499 /// \brief Processes the next node. 1436 1500 /// 1437 /// Processes the next node. And checks that at least one of 1438 /// reached node has true value in the \c nm node map. If one node 1439 /// with true value is reachable from the processed node then the 1440 /// rnode parameter will be set to the first of such nodes. 1441 /// 1442 /// \param nm The node map of possible targets. 1501 /// Processes the next node and checks if at least one of reached 1502 /// nodes has \c true value in the \c nm node map. If one node 1503 /// with \c true value is reachable from the processed node, then the 1504 /// \c rnode parameter will be set to the first of such nodes. 1505 /// 1506 /// \param nm A \c bool (or convertible) node map that indicates the 1507 /// possible targets. 1443 1508 /// \retval rnode The reached target node. 1509 /// It should be initially \c INVALID. 1510 /// 1444 1511 /// \return The processed node. 1445 1512 /// 1446 /// \ warning The queue must not be empty!1513 /// \pre The queue must not be empty. 1447 1514 template <typename NM> 1448 1515 Node processNextNode(const NM& nm, Node& rnode) { … … 1465 1532 } 1466 1533 1467 /// \brief Next node to be processed. 1468 /// 1469 /// Next node to be processed. 1470 /// 1471 /// \return The next node to be processed or INVALID if the stack is 1472 /// empty. 1473 Node nextNode() { 1534 /// \brief The next node to be processed. 1535 /// 1536 /// Returns the next node to be processed or \c INVALID if the queue 1537 /// is empty. 1538 Node nextNode() const { 1474 1539 return _list_front != _list_back ? _list[_list_front + 1] : INVALID; 1475 1540 } 1476 1541 1477 1542 /// \brief Returns \c false if there are nodes 1478 /// to be processed in the queue1543 /// to be processed. 1479 1544 /// 1480 1545 /// Returns \c false if there are nodes 1481 /// to be processed in the queue 1482 bool emptyQueue() { return _list_front == _list_back; }1546 /// to be processed in the queue. 1547 bool emptyQueue() const { return _list_front == _list_back; } 1483 1548 1484 1549 /// \brief Returns the number of the nodes to be processed. 1485 1550 /// 1486 1551 /// Returns the number of the nodes to be processed in the queue. 1487 int queueSize() { return _list_back  _list_front; }1552 int queueSize() const { return _list_back  _list_front; } 1488 1553 1489 1554 /// \brief Executes the algorithm. … … 1491 1556 /// Executes the algorithm. 1492 1557 /// 1493 /// \pre init() must be called and at least one node should be added 1558 /// This method runs the %BFS algorithm from the root node(s) 1559 /// in order to compute the shortest path to each node. 1560 /// 1561 /// The algorithm computes 1562 ///  the shortest path tree (forest), 1563 ///  the distance of each node from the root(s). 1564 /// 1565 /// \pre init() must be called and at least one root node should be added 1494 1566 /// with addSource() before using this function. 1567 /// 1568 /// \note <tt>b.start()</tt> is just a shortcut of the following code. 1569 /// \code 1570 /// while ( !b.emptyQueue() ) { 1571 /// b.processNextNode(); 1572 /// } 1573 /// \endcode 1495 1574 void start() { 1496 1575 while ( !emptyQueue() ) processNextNode(); 1497 1576 } 1498 1577 1499 /// \brief Executes the algorithm until \c dest is reached. 1500 /// 1501 /// Executes the algorithm until \c dest is reached. 1502 /// 1503 /// \pre init() must be called and at least one node should be added 1504 /// with addSource() before using this function. 1578 /// \brief Executes the algorithm until the given target node is reached. 1579 /// 1580 /// Executes the algorithm until the given target node is reached. 1581 /// 1582 /// This method runs the %BFS algorithm from the root node(s) 1583 /// in order to compute the shortest path to \c dest. 1584 /// 1585 /// The algorithm computes 1586 ///  the shortest path to \c dest, 1587 ///  the distance of \c dest from the root(s). 1588 /// 1589 /// \pre init() must be called and at least one root node should be 1590 /// added with addSource() before using this function. 1591 /// 1592 /// \note <tt>b.start(t)</tt> is just a shortcut of the following code. 1593 /// \code 1594 /// bool reach = false; 1595 /// while ( !b.emptyQueue() && !reach ) { 1596 /// b.processNextNode(t, reach); 1597 /// } 1598 /// \endcode 1505 1599 void start(Node dest) { 1506 1600 bool reach = false; … … 1512 1606 /// Executes the algorithm until a condition is met. 1513 1607 /// 1514 /// \pre init() must be called and at least one node should be added 1515 /// with addSource() before using this function. 1516 /// 1517 ///\param nm must be a bool (or convertible) node map. The 1518 ///algorithm will stop when it reaches a node \c v with 1608 /// This method runs the %BFS algorithm from the root node(s) in 1609 /// order to compute the shortest path to a node \c v with 1610 /// <tt>nm[v]</tt> true, if such a node can be found. 1611 /// 1612 /// \param nm must be a bool (or convertible) node map. The 1613 /// algorithm will stop when it reaches a node \c v with 1519 1614 /// <tt>nm[v]</tt> true. 1520 1615 /// 1521 ///\return The reached node \c v with <tt>nm[v]</tt> true or 1522 ///\c INVALID if no such node was found. 1616 /// \return The reached node \c v with <tt>nm[v]</tt> true or 1617 /// \c INVALID if no such node was found. 1618 /// 1619 /// \pre init() must be called and at least one root node should be 1620 /// added with addSource() before using this function. 1621 /// 1622 /// \note <tt>b.start(nm)</tt> is just a shortcut of the following code. 1623 /// \code 1624 /// Node rnode = INVALID; 1625 /// while ( !b.emptyQueue() && rnode == INVALID ) { 1626 /// b.processNextNode(nm, rnode); 1627 /// } 1628 /// return rnode; 1629 /// \endcode 1523 1630 template <typename NM> 1524 1631 Node start(const NM &nm) { … … 1530 1637 } 1531 1638 1532 /// \brief Runs %BFSVisit algorithm from node \c s. 1533 /// 1534 /// This method runs the %BFS algorithm from a root node \c s. 1535 /// \note b.run(s) is just a shortcut of the following code. 1639 /// \brief Runs the algorithm from the given node. 1640 /// 1641 /// This method runs the %BFS algorithm from node \c s 1642 /// in order to compute the shortest path to each node. 1643 /// 1644 /// The algorithm computes 1645 ///  the shortest path tree, 1646 ///  the distance of each node from the root. 1647 /// 1648 /// \note <tt>b.run(s)</tt> is just a shortcut of the following code. 1536 1649 ///\code 1537 1650 /// b.init(); … … 1545 1658 } 1546 1659 1547 /// \brief Runs %BFSVisitalgorithm to visit all nodes in the digraph.1660 /// \brief Runs the algorithm to visit all nodes in the digraph. 1548 1661 /// 1549 1662 /// This method runs the %BFS algorithm in order to 1550 /// compute the %BFS path to each node. The algorithm computes 1551 ///  The %BFS tree. 1552 ///  The distance of each node from the root in the %BFS tree. 1553 /// 1554 ///\note b.run() is just a shortcut of the following code. 1663 /// compute the shortest path to each node. 1664 /// 1665 /// The algorithm computes 1666 ///  the shortest path tree (forest), 1667 ///  the distance of each node from the root(s). 1668 /// 1669 /// \note <tt>b.run(s)</tt> is just a shortcut of the following code. 1555 1670 ///\code 1556 1671 /// b.init(); 1557 /// for (NodeIt it(digraph); it != INVALID; ++it) {1558 /// if (!b.reached( it)) {1559 /// b.addSource( it);1672 /// for (NodeIt n(gr); n != INVALID; ++n) { 1673 /// if (!b.reached(n)) { 1674 /// b.addSource(n); 1560 1675 /// b.start(); 1561 1676 /// } … … 1571 1686 } 1572 1687 } 1688 1573 1689 ///@} 1574 1690 … … 1576 1692 /// The result of the %BFS algorithm can be obtained using these 1577 1693 /// functions.\n 1578 /// Before the use of these functions, 1579 /// either run() or start() must be called. 1694 /// Either \ref lemon::BfsVisit::run() "run()" or 1695 /// \ref lemon::BfsVisit::start() "start()" must be called before 1696 /// using them. 1580 1697 ///@{ 1581 1698 1582 /// \brief Checks if a node is reachable from the root .1699 /// \brief Checks if a node is reachable from the root(s). 1583 1700 /// 1584 1701 /// Returns \c true if \c v is reachable from the root(s). 1585 /// \warning The source nodes are inditated as unreachable.1586 1702 /// \pre Either \ref run() or \ref start() 1587 1703 /// must be called before using this function. 1588 ///1589 1704 bool reached(Node v) { return (*_reached)[v]; } 1705 1590 1706 ///@} 1707 1591 1708 }; 1592 1709 … … 1594 1711 1595 1712 #endif 1596
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