diff -r d8475431bbbb -r 8e85e6bbefdf lemon/bfs.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/lemon/bfs.h Mon May 23 04:48:14 2005 +0000 @@ -0,0 +1,1130 @@ +/* -*- C++ -*- + * lemon/bfs.h - Part of LEMON, a generic C++ optimization library + * + * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport + * (Egervary Research Group on Combinatorial Optimization, EGRES). + * + * Permission to use, modify and distribute this software is granted + * provided that this copyright notice appears in all copies. For + * precise terms see the accompanying LICENSE file. + * + * This software is provided "AS IS" with no warranty of any kind, + * express or implied, and with no claim as to its suitability for any + * purpose. + * + */ + +#ifndef LEMON_BFS_H +#define LEMON_BFS_H + +///\ingroup flowalgs +///\file +///\brief Bfs algorithm. + +#include +#include +#include +#include +#include + +namespace lemon { + + + + ///Default traits class of Bfs class. + + ///Default traits class of Bfs class. + ///\param GR Graph type. + template + struct BfsDefaultTraits + { + ///The graph type the algorithm runs on. + typedef GR Graph; + ///\brief The type of the map that stores the last + ///edges of the shortest paths. + /// + ///The type of the map that stores the last + ///edges of the shortest paths. + ///It must meet the \ref concept::WriteMap "WriteMap" concept. + /// + typedef typename Graph::template NodeMap PredMap; + ///Instantiates a PredMap. + + ///This function instantiates a \ref PredMap. + ///\param G is the graph, to which we would like to define the PredMap. + ///\todo The graph alone may be insufficient to initialize + static PredMap *createPredMap(const GR &G) + { + return new PredMap(G); + } +// ///\brief The type of the map that stores the last but one +// ///nodes of the shortest paths. +// /// +// ///The type of the map that stores the last but one +// ///nodes of the shortest paths. +// ///It must meet the \ref concept::WriteMap "WriteMap" concept. +// /// +// typedef NullMap PredNodeMap; +// ///Instantiates a PredNodeMap. + +// ///This function instantiates a \ref PredNodeMap. +// ///\param G is the graph, to which +// ///we would like to define the \ref PredNodeMap +// static PredNodeMap *createPredNodeMap(const GR &G) +// { +// return new PredNodeMap(); +// } + + ///The type of the map that indicates which nodes are processed. + + ///The type of the map that indicates which nodes are processed. + ///It must meet the \ref concept::WriteMap "WriteMap" concept. + ///\todo named parameter to set this type, function to read and write. + typedef NullMap ProcessedMap; + ///Instantiates a ProcessedMap. + + ///This function instantiates a \ref ProcessedMap. + ///\param G is the graph, to which + ///we would like to define the \ref ProcessedMap + static ProcessedMap *createProcessedMap(const GR &) + { + return new ProcessedMap(); + } + ///The type of the map that indicates which nodes are reached. + + ///The type of the map that indicates which nodes are reached. + ///It must meet the \ref concept::WriteMap "WriteMap" concept. + ///\todo named parameter to set this type, function to read and write. + typedef typename Graph::template NodeMap ReachedMap; + ///Instantiates a ReachedMap. + + ///This function instantiates a \ref ReachedMap. + ///\param G is the graph, to which + ///we would like to define the \ref ReachedMap. + static ReachedMap *createReachedMap(const GR &G) + { + return new ReachedMap(G); + } + ///The type of the map that stores the dists of the nodes. + + ///The type of the map that stores the dists of the nodes. + ///It must meet the \ref concept::WriteMap "WriteMap" concept. + /// + typedef typename Graph::template NodeMap DistMap; + ///Instantiates a DistMap. + + ///This function instantiates a \ref DistMap. + ///\param G is the graph, to which we would like to define the \ref DistMap + static DistMap *createDistMap(const GR &G) + { + return new DistMap(G); + } + }; + + ///%BFS algorithm class. + + ///\ingroup flowalgs + ///This class provides an efficient implementation of the %BFS algorithm. + /// + ///\param GR The graph type the algorithm runs on. The default value is + ///\ref ListGraph. The value of GR is not used directly by Bfs, it + ///is only passed to \ref BfsDefaultTraits. + ///\param TR Traits class to set various data types used by the algorithm. + ///The default traits class is + ///\ref BfsDefaultTraits "BfsDefaultTraits". + ///See \ref BfsDefaultTraits for the documentation of + ///a Bfs traits class. + /// + ///\author Alpar Juttner + ///\todo A compare object would be nice. + +#ifdef DOXYGEN + template +#else + template > +#endif + class Bfs { + public: + /** + * \brief \ref Exception for uninitialized parameters. + * + * This error represents problems in the initialization + * of the parameters of the algorithms. + */ + class UninitializedParameter : public lemon::UninitializedParameter { + public: + virtual const char* exceptionName() const { + return "lemon::Bfs::UninitializedParameter"; + } + }; + + typedef TR Traits; + ///The type of the underlying graph. + typedef typename TR::Graph Graph; + ///\e + typedef typename Graph::Node Node; + ///\e + typedef typename Graph::NodeIt NodeIt; + ///\e + typedef typename Graph::Edge Edge; + ///\e + typedef typename Graph::OutEdgeIt OutEdgeIt; + + ///\brief The type of the map that stores the last + ///edges of the shortest paths. + typedef typename TR::PredMap PredMap; +// ///\brief The type of the map that stores the last but one +// ///nodes of the shortest paths. +// typedef typename TR::PredNodeMap PredNodeMap; + ///The type of the map indicating which nodes are reached. + typedef typename TR::ReachedMap ReachedMap; + ///The type of the map indicating which nodes are processed. + typedef typename TR::ProcessedMap ProcessedMap; + ///The type of the map that stores the dists of the nodes. + typedef typename TR::DistMap DistMap; + private: + /// Pointer to the underlying graph. + const Graph *G; + ///Pointer to the map of predecessors edges. + PredMap *_pred; + ///Indicates if \ref _pred is locally allocated (\c true) or not. + bool local_pred; +// ///Pointer to the map of predecessors nodes. +// PredNodeMap *_predNode; +// ///Indicates if \ref _predNode is locally allocated (\c true) or not. +// bool local_predNode; + ///Pointer to the map of distances. + DistMap *_dist; + ///Indicates if \ref _dist is locally allocated (\c true) or not. + bool local_dist; + ///Pointer to the map of reached status of the nodes. + ReachedMap *_reached; + ///Indicates if \ref _reached is locally allocated (\c true) or not. + bool local_reached; + ///Pointer to the map of processed status of the nodes. + ProcessedMap *_processed; + ///Indicates if \ref _processed is locally allocated (\c true) or not. + bool local_processed; + + std::vector _queue; + int _queue_head,_queue_tail,_queue_next_dist; + int _curr_dist; +// ///The source node of the last execution. +// Node source; + + ///Creates the maps if necessary. + + ///\todo Error if \c G are \c NULL. + ///\todo Better memory allocation (instead of new). + void create_maps() + { + if(!_pred) { + local_pred = true; + _pred = Traits::createPredMap(*G); + } +// if(!_predNode) { +// local_predNode = true; +// _predNode = Traits::createPredNodeMap(*G); +// } + if(!_dist) { + local_dist = true; + _dist = Traits::createDistMap(*G); + } + if(!_reached) { + local_reached = true; + _reached = Traits::createReachedMap(*G); + } + if(!_processed) { + local_processed = true; + _processed = Traits::createProcessedMap(*G); + } + } + + public : + + ///\name Named template parameters + + ///@{ + + template + struct DefPredMapTraits : public Traits { + typedef T PredMap; + static PredMap *createPredMap(const Graph &G) + { + throw UninitializedParameter(); + } + }; + ///\ref named-templ-param "Named parameter" for setting PredMap type + + ///\ref named-templ-param "Named parameter" for setting PredMap type + /// + template + class DefPredMap : public Bfs< Graph, + DefPredMapTraits > { }; + +// template +// struct DefPredNodeMapTraits : public Traits { +// typedef T PredNodeMap; +// static PredNodeMap *createPredNodeMap(const Graph &G) +// { +// throw UninitializedParameter(); +// } +// }; +// ///\ref named-templ-param "Named parameter" for setting PredNodeMap type + +// ///\ref named-templ-param "Named parameter" for setting PredNodeMap type +// /// +// template +// class DefPredNodeMap : public Bfs< Graph, +// LengthMap, +// DefPredNodeMapTraits > { }; + + template + struct DefDistMapTraits : public Traits { + typedef T DistMap; + static DistMap *createDistMap(const Graph &G) + { + throw UninitializedParameter(); + } + }; + ///\ref named-templ-param "Named parameter" for setting DistMap type + + ///\ref named-templ-param "Named parameter" for setting DistMap type + /// + template + class DefDistMap : public Bfs< Graph, + DefDistMapTraits > { }; + + template + struct DefReachedMapTraits : public Traits { + typedef T ReachedMap; + static ReachedMap *createReachedMap(const Graph &G) + { + throw UninitializedParameter(); + } + }; + ///\ref named-templ-param "Named parameter" for setting ReachedMap type + + ///\ref named-templ-param "Named parameter" for setting ReachedMap type + /// + template + class DefReachedMap : public Bfs< Graph, + DefReachedMapTraits > { }; + + struct DefGraphReachedMapTraits : public Traits { + typedef typename Graph::template NodeMap ReachedMap; + static ReachedMap *createReachedMap(const Graph &G) + { + return new ReachedMap(G); + } + }; + template + struct DefProcessedMapTraits : public Traits { + typedef T ProcessedMap; + static ProcessedMap *createProcessedMap(const Graph &G) + { + throw UninitializedParameter(); + } + }; + ///\ref named-templ-param "Named parameter" for setting ProcessedMap type + + ///\ref named-templ-param "Named parameter" for setting ProcessedMap type + /// + template + class DefProcessedMap : public Bfs< Graph, + DefProcessedMapTraits > { }; + + struct DefGraphProcessedMapTraits : public Traits { + typedef typename Graph::template NodeMap ProcessedMap; + static ProcessedMap *createProcessedMap(const Graph &G) + { + return new ProcessedMap(G); + } + }; + ///\brief \ref named-templ-param "Named parameter" + ///for setting the ProcessedMap type to be Graph::NodeMap. + /// + ///\ref named-templ-param "Named parameter" + ///for setting the ProcessedMap type to be Graph::NodeMap. + ///If you don't set it explicitly, it will be automatically allocated. + template + class DefProcessedMapToBeDefaultMap : + public Bfs< Graph, + DefGraphProcessedMapTraits> { }; + + ///@} + + public: + + ///Constructor. + + ///\param _G the graph the algorithm will run on. + /// + Bfs(const Graph& _G) : + G(&_G), + _pred(NULL), local_pred(false), +// _predNode(NULL), local_predNode(false), + _dist(NULL), local_dist(false), + _reached(NULL), local_reached(false), + _processed(NULL), local_processed(false) + { } + + ///Destructor. + ~Bfs() + { + if(local_pred) delete _pred; +// if(local_predNode) delete _predNode; + if(local_dist) delete _dist; + if(local_reached) delete _reached; + if(local_processed) delete _processed; + } + + ///Sets the map storing the predecessor edges. + + ///Sets the map storing the predecessor edges. + ///If you don't use this function before calling \ref run(), + ///it will allocate one. The destructor deallocates this + ///automatically allocated map, of course. + ///\return (*this) + Bfs &predMap(PredMap &m) + { + if(local_pred) { + delete _pred; + local_pred=false; + } + _pred = &m; + return *this; + } + + ///Sets the map indicating the reached nodes. + + ///Sets the map indicating the reached nodes. + ///If you don't use this function before calling \ref run(), + ///it will allocate one. The destructor deallocates this + ///automatically allocated map, of course. + ///\return (*this) + Bfs &reachedMap(ReachedMap &m) + { + if(local_reached) { + delete _reached; + local_reached=false; + } + _reached = &m; + return *this; + } + + ///Sets the map indicating the processed nodes. + + ///Sets the map indicating the processed nodes. + ///If you don't use this function before calling \ref run(), + ///it will allocate one. The destructor deallocates this + ///automatically allocated map, of course. + ///\return (*this) + Bfs &processedMap(ProcessedMap &m) + { + if(local_processed) { + delete _processed; + local_processed=false; + } + _processed = &m; + return *this; + } + +// ///Sets the map storing the predecessor nodes. + +// ///Sets the map storing the predecessor nodes. +// ///If you don't use this function before calling \ref run(), +// ///it will allocate one. The destructor deallocates this +// ///automatically allocated map, of course. +// ///\return (*this) +// Bfs &predNodeMap(PredNodeMap &m) +// { +// if(local_predNode) { +// delete _predNode; +// local_predNode=false; +// } +// _predNode = &m; +// return *this; +// } + + ///Sets the map storing the distances calculated by the algorithm. + + ///Sets the map storing the distances calculated by the algorithm. + ///If you don't use this function before calling \ref run(), + ///it will allocate one. The destructor deallocates this + ///automatically allocated map, of course. + ///\return (*this) + Bfs &distMap(DistMap &m) + { + if(local_dist) { + delete _dist; + local_dist=false; + } + _dist = &m; + return *this; + } + + public: + ///\name Execution control + ///The simplest way to execute the algorithm is to use + ///one of the member functions called \c run(...). + ///\n + ///If you need more control on the execution, + ///first you must call \ref init(), then you can add several source nodes + ///with \ref addSource(). + ///Finally \ref start() will perform the actual path + ///computation. + + ///@{ + + ///Initializes the internal data structures. + + ///Initializes the internal data structures. + /// + void init() + { + create_maps(); + _queue.resize(countNodes(*G)); + _queue_head=_queue_tail=0; + _curr_dist=1; + for ( NodeIt u(*G) ; u!=INVALID ; ++u ) { + _pred->set(u,INVALID); +// _predNode->set(u,INVALID); + _reached->set(u,false); + _processed->set(u,false); + } + } + + ///Adds a new source node. + + ///Adds a new source node to the set of nodes to be processed. + /// + void addSource(Node s) + { + if(!(*_reached)[s]) + { + _reached->set(s,true); + _pred->set(s,INVALID); + _dist->set(s,0); + _queue[_queue_head++]=s; + _queue_next_dist=_queue_head; + } + } + + ///Processes the next node. + + ///Processes the next node. + /// + ///\warning The queue must not be empty! + void processNextNode() + { + if(_queue_tail==_queue_next_dist) { + _curr_dist++; + _queue_next_dist=_queue_head; + } + Node n=_queue[_queue_tail++]; + _processed->set(n,true); + Node m; + for(OutEdgeIt e(*G,n);e!=INVALID;++e) + if(!(*_reached)[m=G->target(e)]) { + _queue[_queue_head++]=m; + _reached->set(m,true); + _pred->set(m,e); +// _pred_node->set(m,n); + _dist->set(m,_curr_dist); + } + } + + ///\brief Returns \c false if there are nodes + ///to be processed in the queue + /// + ///Returns \c false if there are nodes + ///to be processed in the queue + bool emptyQueue() { return _queue_tail==_queue_head; } + ///Returns the number of the nodes to be processed. + + ///Returns the number of the nodes to be processed in the queue. + /// + int queueSize() { return _queue_head-_queue_tail; } + + ///Executes the algorithm. + + ///Executes the algorithm. + /// + ///\pre init() must be called and at least one node should be added + ///with addSource() before using this function. + /// + ///This method runs the %BFS algorithm from the root node(s) + ///in order to + ///compute the + ///shortest path to each node. The algorithm computes + ///- The shortest path tree. + ///- The distance of each node from the root(s). + /// + void start() + { + while ( !emptyQueue() ) processNextNode(); + } + + ///Executes the algorithm until \c dest is reached. + + ///Executes the algorithm until \c dest is reached. + /// + ///\pre init() must be called and at least one node should be added + ///with addSource() before using this function. + /// + ///This method runs the %BFS algorithm from the root node(s) + ///in order to + ///compute the + ///shortest path to \c dest. The algorithm computes + ///- The shortest path to \c dest. + ///- The distance of \c dest from the root(s). + /// + void start(Node dest) + { + while ( !emptyQueue() && _queue[_queue_tail]!=dest ) processNextNode(); + } + + ///Executes the algorithm until a condition is met. + + ///Executes the algorithm until a condition is met. + /// + ///\pre init() must be called and at least one node should be added + ///with addSource() before using this function. + /// + ///\param nm must be a bool (or convertible) node map. The algorithm + ///will stop when it reaches a node \c v with nm[v]==true. + template + void start(const NM &nm) + { + while ( !emptyQueue() && !nm[_queue[_queue_tail]] ) processNextNode(); + } + + ///Runs %BFS algorithm from node \c s. + + ///This method runs the %BFS algorithm from a root node \c s + ///in order to + ///compute the + ///shortest path to each node. The algorithm computes + ///- The shortest path tree. + ///- The distance of each node from the root. + /// + ///\note d.run(s) is just a shortcut of the following code. + ///\code + /// d.init(); + /// d.addSource(s); + /// d.start(); + ///\endcode + void run(Node s) { + init(); + addSource(s); + start(); + } + + ///Finds the shortest path between \c s and \c t. + + ///Finds the shortest path between \c s and \c t. + /// + ///\return The length of the shortest s---t path if there exists one, + ///0 otherwise. + ///\note Apart from the return value, d.run(s) is + ///just a shortcut of the following code. + ///\code + /// d.init(); + /// d.addSource(s); + /// d.start(t); + ///\endcode + int run(Node s,Node t) { + init(); + addSource(s); + start(t); + return reached(t)?_curr_dist-1+(_queue_tail==_queue_next_dist):0; + } + + ///@} + + ///\name Query Functions + ///The result of the %BFS algorithm can be obtained using these + ///functions.\n + ///Before the use of these functions, + ///either run() or start() must be called. + + ///@{ + + ///Copies the shortest path to \c t into \c p + + ///This function copies the shortest path to \c t into \c p. + ///If it \c \t is a source itself or unreachable, then it does not + ///alter \c p. + ///\todo Is it the right way to handle unreachable nodes? + ///\return Returns \c true if a path to \c t was actually copied to \c p, + ///\c false otherwise. + ///\sa DirPath + template + bool getPath(P &p,Node t) + { + if(reached(t)) { + p.clear(); + typename P::Builder b(p); + for(b.setStartNode(t);pred(t)!=INVALID;t=predNode(t)) + b.pushFront(pred(t)); + b.commit(); + return true; + } + return false; + } + + ///The distance of a node from the root(s). + + ///Returns the distance of a node from the root(s). + ///\pre \ref run() must be called before using this function. + ///\warning If node \c v in unreachable from the root(s) the return value + ///of this function is undefined. + int dist(Node v) const { return (*_dist)[v]; } + + ///Returns the 'previous edge' of the shortest path tree. + + ///For a node \c v it returns the 'previous edge' + ///of the shortest path tree, + ///i.e. it returns the last edge of a shortest path from the root(s) to \c + ///v. It is \ref INVALID + ///if \c v is unreachable from the root(s) or \c v is a root. The + ///shortest path tree used here is equal to the shortest path tree used in + ///\ref predNode(Node v). + ///\pre Either \ref run() or \ref start() must be called before using + ///this function. + ///\todo predEdge could be a better name. + Edge pred(Node v) const { return (*_pred)[v];} + + ///Returns the 'previous node' of the shortest path tree. + + ///For a node \c v it returns the 'previous node' + ///of the shortest path tree, + ///i.e. it returns the last but one node from a shortest path from the + ///root(a) to \c /v. + ///It is INVALID if \c v is unreachable from the root(s) or + ///if \c v itself a root. + ///The shortest path tree used here is equal to the shortest path + ///tree used in \ref pred(Node v). + ///\pre Either \ref run() or \ref start() must be called before + ///using this function. + Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID: + G->source((*_pred)[v]); } + + ///Returns a reference to the NodeMap of distances. + + ///Returns a reference to the NodeMap of distances. + ///\pre Either \ref run() or \ref init() must + ///be called before using this function. + const DistMap &distMap() const { return *_dist;} + + ///Returns a reference to the shortest path tree map. + + ///Returns a reference to the NodeMap of the edges of the + ///shortest path tree. + ///\pre Either \ref run() or \ref init() + ///must be called before using this function. + const PredMap &predMap() const { return *_pred;} + +// ///Returns a reference to the map of nodes of shortest paths. + +// ///Returns a reference to the NodeMap of the last but one nodes of the +// ///shortest path tree. +// ///\pre \ref run() must be called before using this function. +// const PredNodeMap &predNodeMap() const { return *_predNode;} + + ///Checks if a node is reachable from the root. + + ///Returns \c true if \c v is reachable from the root. + ///\warning The source nodes are indicated as unreached. + ///\pre Either \ref run() or \ref start() + ///must be called before using this function. + /// + bool reached(Node v) { return (*_reached)[v]; } + + ///@} + }; + + ///Default traits class of Bfs function. + + ///Default traits class of Bfs function. + ///\param GR Graph type. + template + struct BfsWizardDefaultTraits + { + ///The graph type the algorithm runs on. + typedef GR Graph; + ///\brief The type of the map that stores the last + ///edges of the shortest paths. + /// + ///The type of the map that stores the last + ///edges of the shortest paths. + ///It must meet the \ref concept::WriteMap "WriteMap" concept. + /// + typedef NullMap PredMap; + ///Instantiates a PredMap. + + ///This function instantiates a \ref PredMap. + ///\param G is the graph, to which we would like to define the PredMap. + ///\todo The graph alone may be insufficient to initialize + static PredMap *createPredMap(const GR &) + { + return new PredMap(); + } +// ///\brief The type of the map that stores the last but one +// ///nodes of the shortest paths. +// /// +// ///The type of the map that stores the last but one +// ///nodes of the shortest paths. +// ///It must meet the \ref concept::WriteMap "WriteMap" concept. +// /// +// typedef NullMap PredNodeMap; +// ///Instantiates a PredNodeMap. + +// ///This function instantiates a \ref PredNodeMap. +// ///\param G is the graph, to which +// ///we would like to define the \ref PredNodeMap +// static PredNodeMap *createPredNodeMap(const GR &G) +// { +// return new PredNodeMap(); +// } + + ///The type of the map that indicates which nodes are processed. + + ///The type of the map that indicates which nodes are processed. + ///It must meet the \ref concept::WriteMap "WriteMap" concept. + ///\todo named parameter to set this type, function to read and write. + typedef NullMap ProcessedMap; + ///Instantiates a ProcessedMap. + + ///This function instantiates a \ref ProcessedMap. + ///\param G is the graph, to which + ///we would like to define the \ref ProcessedMap + static ProcessedMap *createProcessedMap(const GR &) + { + return new ProcessedMap(); + } + ///The type of the map that indicates which nodes are reached. + + ///The type of the map that indicates which nodes are reached. + ///It must meet the \ref concept::WriteMap "WriteMap" concept. + ///\todo named parameter to set this type, function to read and write. + typedef typename Graph::template NodeMap ReachedMap; + ///Instantiates a ReachedMap. + + ///This function instantiates a \ref ReachedMap. + ///\param G is the graph, to which + ///we would like to define the \ref ReachedMap. + static ReachedMap *createReachedMap(const GR &G) + { + return new ReachedMap(G); + } + ///The type of the map that stores the dists of the nodes. + + ///The type of the map that stores the dists of the nodes. + ///It must meet the \ref concept::WriteMap "WriteMap" concept. + /// + typedef NullMap DistMap; + ///Instantiates a DistMap. + + ///This function instantiates a \ref DistMap. + ///\param G is the graph, to which we would like to define the \ref DistMap + static DistMap *createDistMap(const GR &) + { + return new DistMap(); + } + }; + + /// Default traits used by \ref BfsWizard + + /// To make it easier to use Bfs algorithm + ///we have created a wizard class. + /// This \ref BfsWizard class needs default traits, + ///as well as the \ref Bfs class. + /// The \ref BfsWizardBase is a class to be the default traits of the + /// \ref BfsWizard class. + template + class BfsWizardBase : public BfsWizardDefaultTraits + { + + typedef BfsWizardDefaultTraits Base; + protected: + /// Type of the nodes in the graph. + typedef typename Base::Graph::Node Node; + + /// Pointer to the underlying graph. + void *_g; + ///Pointer to the map of reached nodes. + void *_reached; + ///Pointer to the map of processed nodes. + void *_processed; + ///Pointer to the map of predecessors edges. + void *_pred; +// ///Pointer to the map of predecessors nodes. +// void *_predNode; + ///Pointer to the map of distances. + void *_dist; + ///Pointer to the source node. + Node _source; + + public: + /// Constructor. + + /// This constructor does not require parameters, therefore it initiates + /// all of the attributes to default values (0, INVALID). + BfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0), +// _predNode(0), + _dist(0), _source(INVALID) {} + + /// Constructor. + + /// This constructor requires some parameters, + /// listed in the parameters list. + /// Others are initiated to 0. + /// \param g is the initial value of \ref _g + /// \param s is the initial value of \ref _source + BfsWizardBase(const GR &g, Node s=INVALID) : + _g((void *)&g), _reached(0), _processed(0), _pred(0), +// _predNode(0), + _dist(0), _source(s) {} + + }; + + /// A class to make the usage of Bfs algorithm easier + + /// This class is created to make it easier to use Bfs algorithm. + /// It uses the functions and features of the plain \ref Bfs, + /// but it is much simpler to use it. + /// + /// Simplicity means that the way to change the types defined + /// in the traits class is based on functions that returns the new class + /// and not on templatable built-in classes. + /// When using the plain \ref Bfs + /// the new class with the modified type comes from + /// the original class by using the :: + /// operator. In the case of \ref BfsWizard only + /// a function have to be called and it will + /// return the needed class. + /// + /// It does not have own \ref run method. When its \ref run method is called + /// it initiates a plain \ref Bfs class, and calls the \ref Bfs::run + /// method of it. + template + class BfsWizard : public TR + { + typedef TR Base; + + ///The type of the underlying graph. + typedef typename TR::Graph Graph; + //\e + typedef typename Graph::Node Node; + //\e + typedef typename Graph::NodeIt NodeIt; + //\e + typedef typename Graph::Edge Edge; + //\e + typedef typename Graph::OutEdgeIt OutEdgeIt; + + ///\brief The type of the map that stores + ///the reached nodes + typedef typename TR::ReachedMap ReachedMap; + ///\brief The type of the map that stores + ///the processed nodes + typedef typename TR::ProcessedMap ProcessedMap; + ///\brief The type of the map that stores the last + ///edges of the shortest paths. + typedef typename TR::PredMap PredMap; +// ///\brief The type of the map that stores the last but one +// ///nodes of the shortest paths. +// typedef typename TR::PredNodeMap PredNodeMap; + ///The type of the map that stores the dists of the nodes. + typedef typename TR::DistMap DistMap; + +public: + /// Constructor. + BfsWizard() : TR() {} + + /// Constructor that requires parameters. + + /// Constructor that requires parameters. + /// These parameters will be the default values for the traits class. + BfsWizard(const Graph &g, Node s=INVALID) : + TR(g,s) {} + + ///Copy constructor + BfsWizard(const TR &b) : TR(b) {} + + ~BfsWizard() {} + + ///Runs Bfs algorithm from a given node. + + ///Runs Bfs algorithm from a given node. + ///The node can be given by the \ref source function. + void run() + { + if(Base::_source==INVALID) throw UninitializedParameter(); + Bfs alg(*(Graph*)Base::_g); + if(Base::_reached) + alg.reachedMap(*(ReachedMap*)Base::_reached); + if(Base::_processed) alg.processedMap(*(ProcessedMap*)Base::_processed); + if(Base::_pred) alg.predMap(*(PredMap*)Base::_pred); +// if(Base::_predNode) alg.predNodeMap(*(PredNodeMap*)Base::_predNode); + if(Base::_dist) alg.distMap(*(DistMap*)Base::_dist); + alg.run(Base::_source); + } + + ///Runs Bfs algorithm from the given node. + + ///Runs Bfs algorithm from the given node. + ///\param s is the given source. + void run(Node s) + { + Base::_source=s; + run(); + } + + template + struct DefPredMapBase : public Base { + typedef T PredMap; + static PredMap *createPredMap(const Graph &) { return 0; }; + DefPredMapBase(const TR &b) : TR(b) {} + }; + + ///\brief \ref named-templ-param "Named parameter" + ///function for setting PredMap + /// + /// \ref named-templ-param "Named parameter" + ///function for setting PredMap + /// + template + BfsWizard > predMap(const T &t) + { + Base::_pred=(void *)&t; + return BfsWizard >(*this); + } + + + template + struct DefReachedMapBase : public Base { + typedef T ReachedMap; + static ReachedMap *createReachedMap(const Graph &) { return 0; }; + DefReachedMapBase(const TR &b) : TR(b) {} + }; + + ///\brief \ref named-templ-param "Named parameter" + ///function for setting ReachedMap + /// + /// \ref named-templ-param "Named parameter" + ///function for setting ReachedMap + /// + template + BfsWizard > reachedMap(const T &t) + { + Base::_pred=(void *)&t; + return BfsWizard >(*this); + } + + + template + struct DefProcessedMapBase : public Base { + typedef T ProcessedMap; + static ProcessedMap *createProcessedMap(const Graph &) { return 0; }; + DefProcessedMapBase(const TR &b) : TR(b) {} + }; + + ///\brief \ref named-templ-param "Named parameter" + ///function for setting ProcessedMap + /// + /// \ref named-templ-param "Named parameter" + ///function for setting ProcessedMap + /// + template + BfsWizard > processedMap(const T &t) + { + Base::_pred=(void *)&t; + return BfsWizard >(*this); + } + + +// template +// struct DefPredNodeMapBase : public Base { +// typedef T PredNodeMap; +// static PredNodeMap *createPredNodeMap(const Graph &G) { return 0; }; +// DefPredNodeMapBase(const TR &b) : TR(b) {} +// }; + +// ///\brief \ref named-templ-param "Named parameter" +// ///function for setting PredNodeMap type +// /// +// /// \ref named-templ-param "Named parameter" +// ///function for setting PredNodeMap type +// /// +// template +// BfsWizard > predNodeMap(const T &t) +// { +// Base::_predNode=(void *)&t; +// return BfsWizard >(*this); +// } + + template + struct DefDistMapBase : public Base { + typedef T DistMap; + static DistMap *createDistMap(const Graph &) { return 0; }; + DefDistMapBase(const TR &b) : TR(b) {} + }; + + ///\brief \ref named-templ-param "Named parameter" + ///function for setting DistMap type + /// + /// \ref named-templ-param "Named parameter" + ///function for setting DistMap type + /// + template + BfsWizard > distMap(const T &t) + { + Base::_dist=(void *)&t; + return BfsWizard >(*this); + } + + /// Sets the source node, from which the Bfs algorithm runs. + + /// Sets the source node, from which the Bfs algorithm runs. + /// \param s is the source node. + BfsWizard &source(Node s) + { + Base::_source=s; + return *this; + } + + }; + + ///Function type interface for Bfs algorithm. + + /// \ingroup flowalgs + ///Function type interface for Bfs algorithm. + /// + ///This function also has several + ///\ref named-templ-func-param "named parameters", + ///they are declared as the members of class \ref BfsWizard. + ///The following + ///example shows how to use these parameters. + ///\code + /// bfs(g,source).predMap(preds).run(); + ///\endcode + ///\warning Don't forget to put the \ref BfsWizard::run() "run()" + ///to the end of the parameter list. + ///\sa BfsWizard + ///\sa Bfs + template + BfsWizard > + bfs(const GR &g,typename GR::Node s=INVALID) + { + return BfsWizard >(g,s); + } + +} //END OF NAMESPACE LEMON + +#endif +