# HG changeset patch
# User Alpar Juttner <alpar@cs.elte.hu>
# Date 1217880036 -7200
# Node ID f1158744a1127caf5d637cab2c043d01c9604c32
# Parent 7c67988fca07b73d9258c05d23e72d76788f3af5# Parent c30731a37f91837bfcfba1aac8844f022ef41554
Merge
diff -r 7c67988fca07 -r f1158744a112 lemon/bfs.h
--- a/lemon/bfs.h Wed Jul 30 12:07:48 2008 +0100
+++ b/lemon/bfs.h Mon Aug 04 22:00:36 2008 +0200
@@ -21,7 +21,7 @@
///\ingroup search
///\file
-///\brief Bfs algorithm.
+///\brief BFS algorithm.
#include <lemon/list_graph.h>
#include <lemon/bits/path_dump.h>
@@ -31,8 +31,6 @@
namespace lemon {
-
-
///Default traits class of Bfs class.
///Default traits class of Bfs class.
@@ -40,73 +38,75 @@
template<class GR>
struct BfsDefaultTraits
{
- ///The digraph type the algorithm runs on.
+ ///The type of the digraph the algorithm runs on.
typedef GR Digraph;
- ///\brief The type of the map that stores the last
+
+ ///\brief The type of the map that stores the predecessor
///arcs of the shortest paths.
///
- ///The type of the map that stores the last
+ ///The type of the map that stores the predecessor
///arcs of the shortest paths.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///
- typedef typename Digraph::template NodeMap<typename GR::Arc> PredMap;
- ///Instantiates a PredMap.
+ typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
+ ///Instantiates a \ref PredMap.
///This function instantiates a \ref PredMap.
- ///\param G is the digraph, to which we would like to define the PredMap.
+ ///\param g is the digraph, to which we would like to define the
+ ///\ref PredMap.
///\todo The digraph alone may be insufficient to initialize
- static PredMap *createPredMap(const GR &G)
+ static PredMap *createPredMap(const Digraph &g)
{
- return new PredMap(G);
+ return new PredMap(g);
}
+
///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 concepts::WriteMap "WriteMap" concept.
- ///\todo named parameter to set this type, function to read and write.
+ ///By default it is a NullMap.
typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
- ///Instantiates a ProcessedMap.
+ ///Instantiates a \ref ProcessedMap.
///This function instantiates a \ref ProcessedMap.
///\param g is the digraph, to which
///we would like to define the \ref ProcessedMap
#ifdef DOXYGEN
- static ProcessedMap *createProcessedMap(const GR &g)
+ static ProcessedMap *createProcessedMap(const Digraph &g)
#else
- static ProcessedMap *createProcessedMap(const GR &)
+ static ProcessedMap *createProcessedMap(const Digraph &)
#endif
{
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 concepts::WriteMap "WriteMap" concept.
- ///\todo named parameter to set this type, function to read and write.
+ ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
typedef typename Digraph::template NodeMap<bool> ReachedMap;
- ///Instantiates a ReachedMap.
+ ///Instantiates a \ref ReachedMap.
///This function instantiates a \ref ReachedMap.
- ///\param G is the digraph, to which
+ ///\param g is the digraph, to which
///we would like to define the \ref ReachedMap.
- static ReachedMap *createReachedMap(const GR &G)
+ static ReachedMap *createReachedMap(const Digraph &g)
{
- return new ReachedMap(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.
+ ///The type of the map that stores the distances of the nodes.
+
+ ///The type of the map that stores the distances of the nodes.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///
typedef typename Digraph::template NodeMap<int> DistMap;
- ///Instantiates a DistMap.
+ ///Instantiates a \ref DistMap.
///This function instantiates a \ref DistMap.
- ///\param G is the digraph, to which we would like to define
- ///the \ref DistMap
- static DistMap *createDistMap(const GR &G)
+ ///\param g is the digraph, to which we would like to define the
+ ///\ref DistMap.
+ static DistMap *createDistMap(const Digraph &g)
{
- return new DistMap(G);
+ return new DistMap(g);
}
};
@@ -115,15 +115,18 @@
///\ingroup search
///This class provides an efficient implementation of the %BFS algorithm.
///
- ///\tparam GR The digraph type the algorithm runs on. The default value is
- ///\ref ListDigraph. The value of GR is not used directly by Bfs, it
- ///is only passed to \ref BfsDefaultTraits.
+ ///There is also a \ref bfs() "function type interface" for the BFS
+ ///algorithm, which is convenient in the simplier cases and it can be
+ ///used easier.
+ ///
+ ///\tparam GR The type of the digraph the algorithm runs on.
+ ///The default value is \ref ListDigraph. The value of GR is not used
+ ///directly by \ref Bfs, it is only passed to \ref BfsDefaultTraits.
///\tparam TR Traits class to set various data types used by the algorithm.
///The default traits class is
///\ref BfsDefaultTraits "BfsDefaultTraits<GR>".
///See \ref BfsDefaultTraits for the documentation of
///a Bfs traits class.
-
#ifdef DOXYGEN
template <typename GR,
typename TR>
@@ -133,12 +136,10 @@
#endif
class Bfs {
public:
- /**
- * \brief \ref Exception for uninitialized parameters.
- *
- * This error represents problems in the initialization
- * of the parameters of the algorithms.
- */
+ ///\ref Exception for uninitialized parameters.
+
+ ///This error represents problems in the initialization of the
+ ///parameters of the algorithm.
class UninitializedParameter : public lemon::UninitializedParameter {
public:
virtual const char* what() const throw() {
@@ -146,19 +147,24 @@
}
};
- typedef TR Traits;
- ///The type of the underlying digraph.
+ ///The type of the digraph the algorithm runs on.
typedef typename TR::Digraph Digraph;
- ///\brief The type of the map that stores the last
- ///arcs of the shortest paths.
+ ///\brief The type of the map that stores the predecessor arcs of the
+ ///shortest paths.
typedef typename TR::PredMap PredMap;
- ///The type of the map indicating which nodes are reached.
+ ///The type of the map that stores the distances of the nodes.
+ typedef typename TR::DistMap DistMap;
+ ///The type of the map that indicates which nodes are reached.
typedef typename TR::ReachedMap ReachedMap;
- ///The type of the map indicating which nodes are processed.
+ ///The type of the map that indicates 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;
+ ///The type of the paths.
+ typedef PredMapPath<Digraph, PredMap> Path;
+
+ ///The traits class.
+ typedef TR Traits;
+
private:
typedef typename Digraph::Node Node;
@@ -166,23 +172,23 @@
typedef typename Digraph::Arc Arc;
typedef typename Digraph::OutArcIt OutArcIt;
- /// Pointer to the underlying digraph.
+ //Pointer to the underlying digraph.
const Digraph *G;
- ///Pointer to the map of predecessors arcs.
+ //Pointer to the map of predecessor arcs.
PredMap *_pred;
- ///Indicates if \ref _pred is locally allocated (\c true) or not.
+ //Indicates if _pred is locally allocated (true) or not.
bool local_pred;
- ///Pointer to the map of distances.
+ //Pointer to the map of distances.
DistMap *_dist;
- ///Indicates if \ref _dist is locally allocated (\c true) or not.
+ //Indicates if _dist is locally allocated (true) or not.
bool local_dist;
- ///Pointer to the map of reached status of the nodes.
+ //Pointer to the map of reached status of the nodes.
ReachedMap *_reached;
- ///Indicates if \ref _reached is locally allocated (\c true) or not.
+ //Indicates if _reached is locally allocated (true) or not.
bool local_reached;
- ///Pointer to the map of processed status of the nodes.
+ //Pointer to the map of processed status of the nodes.
ProcessedMap *_processed;
- ///Indicates if \ref _processed is locally allocated (\c true) or not.
+ //Indicates if _processed is locally allocated (true) or not.
bool local_processed;
std::vector<typename Digraph::Node> _queue;
@@ -190,7 +196,6 @@
int _curr_dist;
///Creates the maps if necessary.
-
///\todo Better memory allocation (instead of new).
void create_maps()
{
@@ -233,10 +238,10 @@
}
};
///\brief \ref named-templ-param "Named parameter" for setting
- ///PredMap type
+ ///\ref PredMap type.
///
- ///\ref named-templ-param "Named parameter" for setting PredMap type
- ///
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref PredMap type.
template <class T>
struct DefPredMap : public Bfs< Digraph, DefPredMapTraits<T> > {
typedef Bfs< Digraph, DefPredMapTraits<T> > Create;
@@ -251,10 +256,10 @@
}
};
///\brief \ref named-templ-param "Named parameter" for setting
- ///DistMap type
+ ///\ref DistMap type.
///
- ///\ref named-templ-param "Named parameter" for setting DistMap type
- ///
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref DistMap type.
template <class T>
struct DefDistMap : public Bfs< Digraph, DefDistMapTraits<T> > {
typedef Bfs< Digraph, DefDistMapTraits<T> > Create;
@@ -269,10 +274,10 @@
}
};
///\brief \ref named-templ-param "Named parameter" for setting
- ///ReachedMap type
+ ///\ref ReachedMap type.
///
- ///\ref named-templ-param "Named parameter" for setting ReachedMap type
- ///
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref ReachedMap type.
template <class T>
struct DefReachedMap : public Bfs< Digraph, DefReachedMapTraits<T> > {
typedef Bfs< Digraph, DefReachedMapTraits<T> > Create;
@@ -287,10 +292,10 @@
}
};
///\brief \ref named-templ-param "Named parameter" for setting
- ///ProcessedMap type
+ ///\ref ProcessedMap type.
///
- ///\ref named-templ-param "Named parameter" for setting ProcessedMap type
- ///
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref ProcessedMap type.
template <class T>
struct DefProcessedMap : public Bfs< Digraph, DefProcessedMapTraits<T> > {
typedef Bfs< Digraph, DefProcessedMapTraits<T> > Create;
@@ -298,16 +303,16 @@
struct DefDigraphProcessedMapTraits : public Traits {
typedef typename Digraph::template NodeMap<bool> ProcessedMap;
- static ProcessedMap *createProcessedMap(const Digraph &G)
+ static ProcessedMap *createProcessedMap(const Digraph &g)
{
- return new ProcessedMap(G);
+ return new ProcessedMap(g);
}
};
- ///\brief \ref named-templ-param "Named parameter"
- ///for setting the ProcessedMap type to be Digraph::NodeMap<bool>.
+ ///\brief \ref named-templ-param "Named parameter" for setting
+ ///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
///
- ///\ref named-templ-param "Named parameter"
- ///for setting the ProcessedMap type to be Digraph::NodeMap<bool>.
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
///If you don't set it explicitly, it will be automatically allocated.
template <class T>
struct DefProcessedMapToBeDefaultMap :
@@ -321,10 +326,10 @@
///Constructor.
- ///\param _G the digraph the algorithm will run on.
- ///
- Bfs(const Digraph& _G) :
- G(&_G),
+ ///Constructor.
+ ///\param g The digraph the algorithm runs on.
+ Bfs(const Digraph &g) :
+ G(&g),
_pred(NULL), local_pred(false),
_dist(NULL), local_dist(false),
_reached(NULL), local_reached(false),
@@ -340,9 +345,9 @@
if(local_processed) delete _processed;
}
- ///Sets the map storing the predecessor arcs.
+ ///Sets the map that stores the predecessor arcs.
- ///Sets the map storing the predecessor arcs.
+ ///Sets the map that stores the predecessor arcs.
///If you don't use this function before calling \ref run(),
///it will allocate one. The destructor deallocates this
///automatically allocated map, of course.
@@ -357,9 +362,9 @@
return *this;
}
- ///Sets the map indicating the reached nodes.
+ ///Sets the map that indicates which nodes are reached.
- ///Sets the map indicating the reached nodes.
+ ///Sets the map that indicates which nodes are reached.
///If you don't use this function before calling \ref run(),
///it will allocate one. The destructor deallocates this
///automatically allocated map, of course.
@@ -374,9 +379,9 @@
return *this;
}
- ///Sets the map indicating the processed nodes.
+ ///Sets the map that indicates which nodes are processed.
- ///Sets the map indicating the processed nodes.
+ ///Sets the map that indicates which nodes are processed.
///If you don't use this function before calling \ref run(),
///it will allocate one. The destructor deallocates this
///automatically allocated map, of course.
@@ -391,9 +396,10 @@
return *this;
}
- ///Sets the map storing the distances calculated by the algorithm.
+ ///Sets the map that stores the distances of the nodes.
- ///Sets the map storing the distances calculated by the algorithm.
+ ///Sets the map that stores the distances of the nodes 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.
@@ -409,20 +415,21 @@
}
public:
+
///\name Execution control
///The simplest way to execute the algorithm is to use
- ///one of the member functions called \c run(...).
+ ///one of the member functions called \ref lemon::Bfs::run() "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.
+ ///If you need more control on the execution, first you must call
+ ///\ref lemon::Bfs::init() "init()", then you can add several source
+ ///nodes with \ref lemon::Bfs::addSource() "addSource()".
+ ///Finally \ref lemon::Bfs::start() "start()" will perform the
+ ///actual path computation.
///@{
- ///\brief Initializes the internal data structures.
- ///
+ ///Initializes the internal data structures.
+
///Initializes the internal data structures.
///
void init()
@@ -460,7 +467,7 @@
///
///\return The processed node.
///
- ///\warning The queue must not be empty!
+ ///\pre The queue must not be empty.
Node processNextNode()
{
if(_queue_tail==_queue_next_dist) {
@@ -482,16 +489,17 @@
///Processes the next node.
- ///Processes the next node. And checks that the given target node
+ ///Processes the next node and checks if the given target node
///is reached. If the target node is reachable from the processed
- ///node then the reached parameter will be set true. The reached
- ///parameter should be initially false.
+ ///node, then the \c reach parameter will be set to \c true.
///
///\param target The target node.
- ///\retval reach Indicates that the target node is reached.
+ ///\retval reach Indicates if the target node is reached.
+ ///It should be initially \c false.
+ ///
///\return The processed node.
///
- ///\warning The queue must not be empty!
+ ///\pre The queue must not be empty.
Node processNextNode(Node target, bool& reach)
{
if(_queue_tail==_queue_next_dist) {
@@ -514,16 +522,19 @@
///Processes the next node.
- ///Processes the next node. And checks that at least one of
- ///reached node has true value in the \c nm node map. If one node
- ///with true value is reachable from the processed node then the
- ///rnode parameter will be set to the first of such nodes.
+ ///Processes the next node and checks if at least one of reached
+ ///nodes has \c true value in the \c nm node map. If one node
+ ///with \c true value is reachable from the processed node, then the
+ ///\c rnode parameter will be set to the first of such nodes.
///
- ///\param nm The node map of possible targets.
+ ///\param nm A \c bool (or convertible) node map that indicates the
+ ///possible targets.
///\retval rnode The reached target node.
+ ///It should be initially \c INVALID.
+ ///
///\return The processed node.
///
- ///\warning The queue must not be empty!
+ ///\pre The queue must not be empty.
template<class NM>
Node processNextNode(const NM& nm, Node& rnode)
{
@@ -545,58 +556,73 @@
return n;
}
- ///Next node to be processed.
+ ///The next node to be processed.
- ///Next node to be processed.
- ///
- ///\return The next node to be processed or INVALID if the queue is
- /// empty.
- Node nextNode()
+ ///Returns the next node to be processed or \c INVALID if the queue
+ ///is empty.
+ Node nextNode() const
{
return _queue_tail<_queue_head?_queue[_queue_tail]:INVALID;
}
///\brief Returns \c false if there are nodes
- ///to be processed in the queue
+ ///to be processed.
///
///Returns \c false if there are nodes
- ///to be processed in the queue
- bool emptyQueue() { return _queue_tail==_queue_head; }
+ ///to be processed in the queue.
+ bool emptyQueue() const { 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; }
+ int queueSize() const { 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.
///
- ///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).
+ ///The algorithm computes
+ ///- the shortest path tree (forest),
+ ///- the distance of each node from the root(s).
+ ///
+ ///\pre init() must be called and at least one root node should be
+ ///added with addSource() before using this function.
+ ///
+ ///\note <tt>b.start()</tt> is just a shortcut of the following code.
+ ///\code
+ /// while ( !b.emptyQueue() ) {
+ /// b.processNextNode();
+ /// }
+ ///\endcode
void start()
{
while ( !emptyQueue() ) processNextNode();
}
- ///Executes the algorithm until \c dest is reached.
+ ///Executes the algorithm until the given target node 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.
+ ///Executes the algorithm until the given target node is reached.
///
///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).
+ ///- the shortest path to \c dest,
+ ///- the distance of \c dest from the root(s).
+ ///
+ ///\pre init() must be called and at least one root node should be
+ ///added with addSource() before using this function.
+ ///
+ ///\note <tt>b.start(t)</tt> is just a shortcut of the following code.
+ ///\code
+ /// bool reach = false;
+ /// while ( !b.emptyQueue() && !reach ) {
+ /// b.processNextNode(t, reach);
+ /// }
+ ///\endcode
void start(Node dest)
{
bool reach = false;
@@ -607,17 +633,29 @@
///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.
+ ///This method runs the %BFS algorithm from the root node(s) in
+ ///order to compute the shortest path to a node \c v with
+ /// <tt>nm[v]</tt> true, if such a node can be found.
///
- ///\param nm must be a bool (or convertible) node map. The
- ///algorithm will stop when it reaches a node \c v with
- /// <tt>nm[v]</tt> true.
+ ///\param nm A \c bool (or convertible) node map. The algorithm
+ ///will stop when it reaches a node \c v with <tt>nm[v]</tt> true.
///
///\return The reached node \c v with <tt>nm[v]</tt> true or
///\c INVALID if no such node was found.
- template<class NM>
- Node start(const NM &nm)
+ ///
+ ///\pre init() must be called and at least one root node should be
+ ///added with addSource() before using this function.
+ ///
+ ///\note <tt>b.start(nm)</tt> is just a shortcut of the following code.
+ ///\code
+ /// Node rnode = INVALID;
+ /// while ( !b.emptyQueue() && rnode == INVALID ) {
+ /// b.processNextNode(nm, rnode);
+ /// }
+ /// return rnode;
+ ///\endcode
+ template<class NodeBoolMap>
+ Node start(const NodeBoolMap &nm)
{
Node rnode = INVALID;
while ( !emptyQueue() && rnode == INVALID ) {
@@ -626,16 +664,16 @@
return rnode;
}
- ///Runs %BFS algorithm from node \c s.
+ ///Runs the algorithm from the given node.
- ///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.
+ ///This method runs the %BFS algorithm from node \c s
+ ///in order to compute the shortest path to each node.
///
- ///\note b.run(s) is just a shortcut of the following code.
+ ///The algorithm computes
+ ///- the shortest path tree,
+ ///- the distance of each node from the root.
+ ///
+ ///\note <tt>b.run(s)</tt> is just a shortcut of the following code.
///\code
/// b.init();
/// b.addSource(s);
@@ -649,12 +687,14 @@
///Finds the shortest path between \c s and \c t.
- ///Finds the shortest path between \c s and \c t.
+ ///This method runs the %BFS algorithm from node \c s
+ ///in order to compute the shortest path to \c t.
///
- ///\return The length of the shortest s---t path if there exists one,
- ///0 otherwise.
- ///\note Apart from the return value, b.run(s) is
- ///just a shortcut of the following code.
+ ///\return The length of the shortest <tt>s</tt>--<tt>t</tt> path,
+ ///if \c t is reachable form \c s, \c 0 otherwise.
+ ///
+ ///\note Apart from the return value, <tt>b.run(s,t)</tt> is just a
+ ///shortcut of the following code.
///\code
/// b.init();
/// b.addSource(s);
@@ -667,116 +707,152 @@
return reached(t) ? _curr_dist : 0;
}
+ ///Runs the algorithm to visit all nodes in the digraph.
+
+ ///This method runs the %BFS algorithm in order to
+ ///compute the shortest path to each node.
+ ///
+ ///The algorithm computes
+ ///- the shortest path tree (forest),
+ ///- the distance of each node from the root(s).
+ ///
+ ///\note <tt>b.run(s)</tt> is just a shortcut of the following code.
+ ///\code
+ /// b.init();
+ /// for (NodeIt n(gr); n != INVALID; ++n) {
+ /// if (!b.reached(n)) {
+ /// b.addSource(n);
+ /// b.start();
+ /// }
+ /// }
+ ///\endcode
+ void run() {
+ init();
+ for (NodeIt n(*G); n != INVALID; ++n) {
+ if (!reached(n)) {
+ addSource(n);
+ start();
+ }
+ }
+ }
+
///@}
///\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 calleb.
+ ///Either \ref lemon::Bfs::run() "run()" or \ref lemon::Bfs::start()
+ ///"start()" must be called before using them.
///@{
- typedef PredMapPath<Digraph, PredMap> Path;
+ ///The shortest path to a node.
- ///Gives back the shortest path.
-
- ///Gives back the shortest path.
- ///\pre The \c t should be reachable from the source.
- Path path(Node t)
- {
- return Path(*G, *_pred, t);
- }
+ ///Returns the shortest path to a node.
+ ///
+ ///\warning \c t should be reachable from the root(s).
+ ///
+ ///\pre Either \ref run() or \ref start() must be called before
+ ///using this function.
+ Path path(Node t) const { return Path(*G, *_pred, t); }
///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.
+ ///
+ ///\warning If node \c v is not reachable from the root(s), then
+ ///the return value of this function is undefined.
+ ///
+ ///\pre Either \ref run() or \ref start() must be called before
+ ///using this function.
int dist(Node v) const { return (*_dist)[v]; }
- ///Returns the 'previous arc' of the shortest path tree.
+ ///Returns the 'previous arc' of the shortest path tree for a node.
- ///For a node \c v it returns the 'previous arc'
- ///of the shortest path tree,
- ///i.e. it returns the last arc 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().
- ///\pre Either \ref run() or \ref start() must be called before using
- ///this function.
+ ///This function returns the 'previous arc' of the shortest path
+ ///tree for the node \c v, i.e. it returns the last arc of a
+ ///shortest path from the root(s) to \c v. It is \c INVALID if \c v
+ ///is not reachable from the root(s) or if \c v is a root.
+ ///
+ ///The shortest path tree used here is equal to the shortest path
+ ///tree used in \ref predNode().
+ ///
+ ///\pre Either \ref run() or \ref start() must be called before
+ ///using this function.
Arc predArc(Node v) const { return (*_pred)[v];}
- ///Returns the 'previous node' of the shortest path tree.
+ ///Returns the 'previous node' of the shortest path tree for a node.
- ///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.
+ ///This function returns the 'previous node' of the shortest path
+ ///tree for the node \c v, i.e. it returns the last but one node
+ ///from a shortest path from the root(s) to \c v. It is \c INVALID
+ ///if \c v is not reachable from the root(s) or if \c v is a root.
+ ///
///The shortest path tree used here is equal to the shortest path
///tree used in \ref predArc().
+ ///
///\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.
+ ///\brief Returns a const reference to the node map that stores the
+ /// distances of the nodes.
+ ///
+ ///Returns a const reference to the node map that stores the distances
+ ///of the nodes calculated by the algorithm.
+ ///
+ ///\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 arcs of the
- ///shortest path tree.
+ ///\brief Returns a const reference to the node map that stores the
+ ///predecessor arcs.
+ ///
+ ///Returns a const reference to the node map that stores the predecessor
+ ///arcs, which form the shortest path tree.
+ ///
///\pre Either \ref run() or \ref init()
///must be called before using this function.
const PredMap &predMap() const { return *_pred;}
- ///Checks if a node is reachable from the root.
+ ///Checks if a node is reachable from the root(s).
- ///Returns \c true if \c v is reachable from the root.
- ///\warning The source nodes are indicated as unreached.
+ ///Returns \c true if \c v is reachable from the root(s).
///\pre Either \ref run() or \ref start()
///must be called before using this function.
- ///
- bool reached(Node v) { return (*_reached)[v]; }
+ bool reached(Node v) const { return (*_reached)[v]; }
///@}
};
- ///Default traits class of Bfs function.
+ ///Default traits class of bfs() function.
- ///Default traits class of Bfs function.
+ ///Default traits class of bfs() function.
///\tparam GR Digraph type.
template<class GR>
struct BfsWizardDefaultTraits
{
- ///The digraph type the algorithm runs on.
+ ///The type of the digraph the algorithm runs on.
typedef GR Digraph;
- ///\brief The type of the map that stores the last
+
+ ///\brief The type of the map that stores the predecessor
///arcs of the shortest paths.
///
- ///The type of the map that stores the last
+ ///The type of the map that stores the predecessor
///arcs of the shortest paths.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///
- typedef NullMap<typename Digraph::Node,typename GR::Arc> PredMap;
- ///Instantiates a PredMap.
+ typedef NullMap<typename Digraph::Node,typename Digraph::Arc> PredMap;
+ ///Instantiates a \ref PredMap.
///This function instantiates a \ref PredMap.
- ///\param g is the digraph, to which we would like to define the PredMap.
+ ///\param g is the digraph, to which we would like to define the
+ ///\ref PredMap.
///\todo The digraph alone may be insufficient to initialize
#ifdef DOXYGEN
- static PredMap *createPredMap(const GR &g)
+ static PredMap *createPredMap(const Digraph &g)
#else
- static PredMap *createPredMap(const GR &)
+ static PredMap *createPredMap(const Digraph &)
#endif
{
return new PredMap();
@@ -786,63 +862,63 @@
///The type of the map that indicates which nodes are processed.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///\todo named parameter to set this type, function to read and write.
typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
- ///Instantiates a ProcessedMap.
+ ///Instantiates a \ref ProcessedMap.
///This function instantiates a \ref ProcessedMap.
///\param g is the digraph, to which
- ///we would like to define the \ref ProcessedMap
+ ///we would like to define the \ref ProcessedMap.
#ifdef DOXYGEN
- static ProcessedMap *createProcessedMap(const GR &g)
+ static ProcessedMap *createProcessedMap(const Digraph &g)
#else
- static ProcessedMap *createProcessedMap(const GR &)
+ static ProcessedMap *createProcessedMap(const Digraph &)
#endif
{
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 concepts::WriteMap "WriteMap" concept.
- ///\todo named parameter to set this type, function to read and write.
+ ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
typedef typename Digraph::template NodeMap<bool> ReachedMap;
- ///Instantiates a ReachedMap.
+ ///Instantiates a \ref ReachedMap.
///This function instantiates a \ref ReachedMap.
- ///\param G is the digraph, to which
+ ///\param g is the digraph, to which
///we would like to define the \ref ReachedMap.
- static ReachedMap *createReachedMap(const GR &G)
+ static ReachedMap *createReachedMap(const Digraph &g)
{
- return new ReachedMap(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.
+ ///The type of the map that stores the distances of the nodes.
+
+ ///The type of the map that stores the distances of the nodes.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
///
typedef NullMap<typename Digraph::Node,int> DistMap;
- ///Instantiates a DistMap.
+ ///Instantiates a \ref DistMap.
///This function instantiates a \ref DistMap.
///\param g is the digraph, to which we would like to define
///the \ref DistMap
#ifdef DOXYGEN
- static DistMap *createDistMap(const GR &g)
+ static DistMap *createDistMap(const Digraph &g)
#else
- static DistMap *createDistMap(const GR &)
+ static DistMap *createDistMap(const Digraph &)
#endif
{
return new DistMap();
}
};
- /// Default traits used by \ref BfsWizard
+ /// Default traits class used by \ref BfsWizard
/// To make it easier to use Bfs algorithm
- ///we have created a wizard class.
+ /// we have created a wizard class.
/// This \ref BfsWizard class needs default traits,
- ///as well as the \ref Bfs class.
+ /// 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 GR>
@@ -851,20 +927,20 @@
typedef BfsWizardDefaultTraits<GR> Base;
protected:
- /// Type of the nodes in the digraph.
+ //The type of the nodes in the digraph.
typedef typename Base::Digraph::Node Node;
- /// Pointer to the underlying digraph.
+ //Pointer to the digraph the algorithm runs on.
void *_g;
- ///Pointer to the map of reached nodes.
+ //Pointer to the map of reached nodes.
void *_reached;
- ///Pointer to the map of processed nodes.
+ //Pointer to the map of processed nodes.
void *_processed;
- ///Pointer to the map of predecessors arcs.
+ //Pointer to the map of predecessors arcs.
void *_pred;
- ///Pointer to the map of distances.
+ //Pointer to the map of distances.
void *_dist;
- ///Pointer to the source node.
+ //Pointer to the source node.
Node _source;
public:
@@ -873,26 +949,28 @@
/// 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),
- _dist(0), _source(INVALID) {}
+ _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
+ /// \param g The digraph the algorithm runs on.
+ /// \param s The source node.
BfsWizardBase(const GR &g, Node s=INVALID) :
_g(reinterpret_cast<void*>(const_cast<GR*>(&g))),
_reached(0), _processed(0), _pred(0), _dist(0), _source(s) {}
};
- /// A class to make the usage of Bfs algorithm easier
+ /// Auxiliary class for the function type interface of BFS algorithm.
- /// 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.
+ /// This auxiliary class is created to implement the function type
+ /// interface of \ref Bfs algorithm. It uses the functions and features
+ /// of the plain \ref Bfs, but it is much simpler to use it.
+ /// It should only be used through the \ref bfs() function, which makes
+ /// it easier to use the algorithm.
///
/// Simplicity means that the way to change the types defined
/// in the traits class is based on functions that returns the new class
@@ -901,41 +979,37 @@
/// 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
+ /// 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.
+ /// It does not have own \ref run() method. When its \ref run() method
+ /// is called, it initiates a plain \ref Bfs object, and calls the
+ /// \ref Bfs::run() method of it.
template<class TR>
class BfsWizard : public TR
{
typedef TR Base;
- ///The type of the underlying digraph.
+ ///The type of the digraph the algorithm runs on.
typedef typename TR::Digraph Digraph;
- //\e
+
typedef typename Digraph::Node Node;
- //\e
typedef typename Digraph::NodeIt NodeIt;
- //\e
typedef typename Digraph::Arc Arc;
- //\e
typedef typename Digraph::OutArcIt OutArcIt;
- ///\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
+ ///\brief The type of the map that stores the predecessor
///arcs of the shortest paths.
typedef typename TR::PredMap PredMap;
- ///The type of the map that stores the dists of the nodes.
+ ///\brief The type of the map that stores the distances of the nodes.
typedef typename TR::DistMap DistMap;
+ ///\brief The type of the map that indicates which nodes are reached.
+ typedef typename TR::ReachedMap ReachedMap;
+ ///\brief The type of the map that indicates which nodes are processed.
+ typedef typename TR::ProcessedMap ProcessedMap;
public:
+
/// Constructor.
BfsWizard() : TR() {}
@@ -951,10 +1025,10 @@
~BfsWizard() {}
- ///Runs Bfs algorithm from a given node.
+ ///Runs BFS algorithm from a source node.
- ///Runs Bfs algorithm from a given node.
- ///The node can be given by the \ref source function.
+ ///Runs BFS algorithm from a source node.
+ ///The node can be given with the \ref source() function.
void run()
{
if(Base::_source==INVALID) throw UninitializedParameter();
@@ -970,9 +1044,9 @@
alg.run(Base::_source);
}
- ///Runs Bfs algorithm from the given node.
+ ///Runs BFS algorithm from the given node.
- ///Runs Bfs algorithm from the given node.
+ ///Runs BFS algorithm from the given node.
///\param s is the given source.
void run(Node s)
{
@@ -980,89 +1054,6 @@
run();
}
- template<class T>
- struct DefPredMapBase : public Base {
- typedef T PredMap;
- static PredMap *createPredMap(const Digraph &) { 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<class T>
- BfsWizard<DefPredMapBase<T> > predMap(const T &t)
- {
- Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t));
- return BfsWizard<DefPredMapBase<T> >(*this);
- }
-
-
- template<class T>
- struct DefReachedMapBase : public Base {
- typedef T ReachedMap;
- static ReachedMap *createReachedMap(const Digraph &) { 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<class T>
- BfsWizard<DefReachedMapBase<T> > reachedMap(const T &t)
- {
- Base::_reached=reinterpret_cast<void*>(const_cast<T*>(&t));
- return BfsWizard<DefReachedMapBase<T> >(*this);
- }
-
-
- template<class T>
- struct DefProcessedMapBase : public Base {
- typedef T ProcessedMap;
- static ProcessedMap *createProcessedMap(const Digraph &) { 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<class T>
- BfsWizard<DefProcessedMapBase<T> > processedMap(const T &t)
- {
- Base::_processed=reinterpret_cast<void*>(const_cast<T*>(&t));
- return BfsWizard<DefProcessedMapBase<T> >(*this);
- }
-
-
- template<class T>
- struct DefDistMapBase : public Base {
- typedef T DistMap;
- static DistMap *createDistMap(const Digraph &) { 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<class T>
- BfsWizard<DefDistMapBase<T> > distMap(const T &t)
- {
- Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t));
- return BfsWizard<DefDistMapBase<T> >(*this);
- }
-
/// Sets the source node, from which the Bfs algorithm runs.
/// Sets the source node, from which the Bfs algorithm runs.
@@ -1073,6 +1064,78 @@
return *this;
}
+ template<class T>
+ struct DefPredMapBase : public Base {
+ typedef T PredMap;
+ static PredMap *createPredMap(const Digraph &) { return 0; };
+ DefPredMapBase(const TR &b) : TR(b) {}
+ };
+ ///\brief \ref named-templ-param "Named parameter"
+ ///for setting \ref PredMap object.
+ ///
+ /// \ref named-templ-param "Named parameter"
+ ///for setting \ref PredMap object.
+ template<class T>
+ BfsWizard<DefPredMapBase<T> > predMap(const T &t)
+ {
+ Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t));
+ return BfsWizard<DefPredMapBase<T> >(*this);
+ }
+
+ template<class T>
+ struct DefReachedMapBase : public Base {
+ typedef T ReachedMap;
+ static ReachedMap *createReachedMap(const Digraph &) { return 0; };
+ DefReachedMapBase(const TR &b) : TR(b) {}
+ };
+ ///\brief \ref named-templ-param "Named parameter"
+ ///for setting \ref ReachedMap object.
+ ///
+ /// \ref named-templ-param "Named parameter"
+ ///for setting \ref ReachedMap object.
+ template<class T>
+ BfsWizard<DefReachedMapBase<T> > reachedMap(const T &t)
+ {
+ Base::_reached=reinterpret_cast<void*>(const_cast<T*>(&t));
+ return BfsWizard<DefReachedMapBase<T> >(*this);
+ }
+
+ template<class T>
+ struct DefProcessedMapBase : public Base {
+ typedef T ProcessedMap;
+ static ProcessedMap *createProcessedMap(const Digraph &) { return 0; };
+ DefProcessedMapBase(const TR &b) : TR(b) {}
+ };
+ ///\brief \ref named-templ-param "Named parameter"
+ ///for setting \ref ProcessedMap object.
+ ///
+ /// \ref named-templ-param "Named parameter"
+ ///for setting \ref ProcessedMap object.
+ template<class T>
+ BfsWizard<DefProcessedMapBase<T> > processedMap(const T &t)
+ {
+ Base::_processed=reinterpret_cast<void*>(const_cast<T*>(&t));
+ return BfsWizard<DefProcessedMapBase<T> >(*this);
+ }
+
+ template<class T>
+ struct DefDistMapBase : public Base {
+ typedef T DistMap;
+ static DistMap *createDistMap(const Digraph &) { return 0; };
+ DefDistMapBase(const TR &b) : TR(b) {}
+ };
+ ///\brief \ref named-templ-param "Named parameter"
+ ///for setting \ref DistMap object.
+ ///
+ /// \ref named-templ-param "Named parameter"
+ ///for setting \ref DistMap object.
+ template<class T>
+ BfsWizard<DefDistMapBase<T> > distMap(const T &t)
+ {
+ Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t));
+ return BfsWizard<DefDistMapBase<T> >(*this);
+ }
+
};
///Function type interface for Bfs algorithm.
@@ -1100,38 +1163,38 @@
}
#ifdef DOXYGEN
- /// \brief Visitor class for bfs.
+ /// \brief Visitor class for BFS.
///
/// This class defines the interface of the BfsVisit events, and
- /// it could be the base of a real Visitor class.
+ /// it could be the base of a real visitor class.
template <typename _Digraph>
struct BfsVisitor {
typedef _Digraph Digraph;
typedef typename Digraph::Arc Arc;
typedef typename Digraph::Node Node;
- /// \brief Called when the arc reach a node.
+ /// \brief Called for the source node(s) of the BFS.
///
- /// It is called when the bfs find an arc which target is not
- /// reached yet.
+ /// This function is called for the source node(s) of the BFS.
+ void start(const Node& node) {}
+ /// \brief Called when a node is reached first time.
+ ///
+ /// This function is called when a node is reached first time.
+ void reach(const Node& node) {}
+ /// \brief Called when a node is processed.
+ ///
+ /// This function is called when a node is processed.
+ void process(const Node& node) {}
+ /// \brief Called when an arc reaches a new node.
+ ///
+ /// This function is called when the BFS finds an arc whose target node
+ /// is not reached yet.
void discover(const Arc& arc) {}
- /// \brief Called when the node reached first time.
- ///
- /// It is Called when the node reached first time.
- void reach(const Node& node) {}
- /// \brief Called when the arc examined but target of the arc
+ /// \brief Called when an arc is examined but its target node is
/// already discovered.
///
- /// It called when the arc examined but the target of the arc
+ /// This function is called when an arc is examined but its target node is
/// already discovered.
void examine(const Arc& arc) {}
- /// \brief Called for the source node of the bfs.
- ///
- /// It is called for the source node of the bfs.
- void start(const Node& node) {}
- /// \brief Called when the node processed.
- ///
- /// It is Called when the node processed.
- void process(const Node& node) {}
};
#else
template <typename _Digraph>
@@ -1139,22 +1202,22 @@
typedef _Digraph Digraph;
typedef typename Digraph::Arc Arc;
typedef typename Digraph::Node Node;
+ void start(const Node&) {}
+ void reach(const Node&) {}
+ void process(const Node&) {}
void discover(const Arc&) {}
- void reach(const Node&) {}
void examine(const Arc&) {}
- void start(const Node&) {}
- void process(const Node&) {}
template <typename _Visitor>
struct Constraints {
void constraints() {
Arc arc;
Node node;
+ visitor.start(node);
+ visitor.reach(node);
+ visitor.process(node);
visitor.discover(arc);
- visitor.reach(node);
visitor.examine(arc);
- visitor.start(node);
- visitor.process(node);
}
_Visitor& visitor;
};
@@ -1164,21 +1227,20 @@
/// \brief Default traits class of BfsVisit class.
///
/// Default traits class of BfsVisit class.
- /// \tparam _Digraph Digraph type.
+ /// \tparam _Digraph The type of the digraph the algorithm runs on.
template<class _Digraph>
struct BfsVisitDefaultTraits {
- /// \brief The digraph type the algorithm runs on.
+ /// \brief The type of the digraph the algorithm runs on.
typedef _Digraph Digraph;
/// \brief 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 concepts::WriteMap "WriteMap" concept.
- /// \todo named parameter to set this type, function to read and write.
+ /// It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
typedef typename Digraph::template NodeMap<bool> ReachedMap;
- /// \brief Instantiates a ReachedMap.
+ /// \brief Instantiates a \ref ReachedMap.
///
/// This function instantiates a \ref ReachedMap.
/// \param digraph is the digraph, to which
@@ -1191,28 +1253,28 @@
/// \ingroup search
///
- /// \brief %BFS Visit algorithm class.
+ /// \brief %BFS algorithm class with visitor interface.
///
/// This class provides an efficient implementation of the %BFS algorithm
/// with visitor interface.
///
/// The %BfsVisit class provides an alternative interface to the Bfs
/// class. It works with callback mechanism, the BfsVisit object calls
- /// on every bfs event the \c Visitor class member functions.
+ /// the member functions of the \c Visitor class on every BFS event.
///
- /// \tparam _Digraph The digraph type the algorithm runs on.
+ /// \tparam _Digraph The type of the digraph the algorithm runs on.
/// The default value is
- /// \ref ListDigraph. The value of _Digraph is not used directly by Bfs, it
- /// is only passed to \ref BfsDefaultTraits.
- /// \tparam _Visitor The Visitor object for the algorithm. The
- /// \ref BfsVisitor "BfsVisitor<_Digraph>" is an empty Visitor which
- /// does not observe the Bfs events. If you want to observe the bfs
- /// events you should implement your own Visitor class.
+ /// \ref ListDigraph. The value of _Digraph is not used directly by
+ /// \ref BfsVisit, it is only passed to \ref BfsVisitDefaultTraits.
+ /// \tparam _Visitor The Visitor type that is used by the algorithm.
+ /// \ref BfsVisitor "BfsVisitor<_Digraph>" is an empty visitor, which
+ /// does not observe the BFS events. If you want to observe the BFS
+ /// events, you should implement your own visitor class.
/// \tparam _Traits Traits class to set various data types used by the
/// algorithm. The default traits class is
/// \ref BfsVisitDefaultTraits "BfsVisitDefaultTraits<_Digraph>".
/// See \ref BfsVisitDefaultTraits for the documentation of
- /// a Bfs visit traits class.
+ /// a BFS visit traits class.
#ifdef DOXYGEN
template <typename _Digraph, typename _Visitor, typename _Traits>
#else
@@ -1226,7 +1288,7 @@
/// \brief \ref Exception for uninitialized parameters.
///
/// This error represents problems in the initialization
- /// of the parameters of the algorithms.
+ /// of the parameters of the algorithm.
class UninitializedParameter : public lemon::UninitializedParameter {
public:
virtual const char* what() const throw()
@@ -1235,13 +1297,16 @@
}
};
+ ///The traits class.
typedef _Traits Traits;
+ ///The type of the digraph the algorithm runs on.
typedef typename Traits::Digraph Digraph;
+ ///The visitor type used by the algorithm.
typedef _Visitor Visitor;
- ///The type of the map indicating which nodes are reached.
+ ///The type of the map that indicates which nodes are reached.
typedef typename Traits::ReachedMap ReachedMap;
private:
@@ -1251,21 +1316,20 @@
typedef typename Digraph::Arc Arc;
typedef typename Digraph::OutArcIt OutArcIt;
- /// Pointer to the underlying digraph.
+ //Pointer to the underlying digraph.
const Digraph *_digraph;
- /// Pointer to the visitor object.
+ //Pointer to the visitor object.
Visitor *_visitor;
- ///Pointer to the map of reached status of the nodes.
+ //Pointer to the map of reached status of the nodes.
ReachedMap *_reached;
- ///Indicates if \ref _reached is locally allocated (\c true) or not.
+ //Indicates if _reached is locally allocated (true) or not.
bool local_reached;
std::vector<typename Digraph::Node> _list;
int _list_front, _list_back;
- /// \brief Creates the maps if necessary.
- ///
- /// Creates the maps if necessary.
+ ///Creates the maps if necessary.
+ ///\todo Better memory allocation (instead of new).
void create_maps() {
if(!_reached) {
local_reached = true;
@@ -1292,9 +1356,9 @@
}
};
/// \brief \ref named-templ-param "Named parameter" for setting
- /// ReachedMap type
+ /// ReachedMap type.
///
- /// \ref named-templ-param "Named parameter" for setting ReachedMap type
+ /// \ref named-templ-param "Named parameter" for setting ReachedMap type.
template <class T>
struct DefReachedMap : public BfsVisit< Digraph, Visitor,
DefReachedMapTraits<T> > {
@@ -1308,25 +1372,22 @@
///
/// Constructor.
///
- /// \param digraph the digraph the algorithm will run on.
- /// \param visitor The visitor of the algorithm.
- ///
+ /// \param digraph The digraph the algorithm runs on.
+ /// \param visitor The visitor object of the algorithm.
BfsVisit(const Digraph& digraph, Visitor& visitor)
: _digraph(&digraph), _visitor(&visitor),
_reached(0), local_reached(false) {}
/// \brief Destructor.
- ///
- /// Destructor.
~BfsVisit() {
if(local_reached) delete _reached;
}
- /// \brief Sets the map indicating if a node is reached.
+ /// \brief Sets the map that indicates which nodes are reached.
///
- /// Sets the map indicating if a node is reached.
+ /// Sets the map that indicates which nodes are reached.
/// If you don't use this function before calling \ref run(),
- /// it will allocate one. The destuctor deallocates this
+ /// it will allocate one. The destructor deallocates this
/// automatically allocated map, of course.
/// \return <tt> (*this) </tt>
BfsVisit &reachedMap(ReachedMap &m) {
@@ -1339,21 +1400,23 @@
}
public:
+
/// \name Execution control
/// The simplest way to execute the algorithm is to use
- /// one of the member functions called \c run(...).
+ /// one of the member functions called \ref lemon::BfsVisit::run()
+ /// "run()".
/// \n
- /// If you need more control on the execution,
- /// first you must call \ref init(), then you can adda source node
- /// with \ref addSource().
- /// Finally \ref start() will perform the actual path
- /// computation.
+ /// If you need more control on the execution, first you must call
+ /// \ref lemon::BfsVisit::init() "init()", then you can add several
+ /// source nodes with \ref lemon::BfsVisit::addSource() "addSource()".
+ /// Finally \ref lemon::BfsVisit::start() "start()" will perform the
+ /// actual path computation.
/// @{
+
/// \brief Initializes the internal data structures.
///
/// Initializes the internal data structures.
- ///
void init() {
create_maps();
_list.resize(countNodes(*_digraph));
@@ -1381,7 +1444,7 @@
///
/// \return The processed node.
///
- /// \pre The queue must not be empty!
+ /// \pre The queue must not be empty.
Node processNextNode() {
Node n = _list[++_list_front];
_visitor->process(n);
@@ -1402,16 +1465,17 @@
/// \brief Processes the next node.
///
- /// Processes the next node. And checks that the given target node
+ /// Processes the next node and checks if the given target node
/// is reached. If the target node is reachable from the processed
- /// node then the reached parameter will be set true. The reached
- /// parameter should be initially false.
+ /// node, then the \c reach parameter will be set to \c true.
///
/// \param target The target node.
- /// \retval reach Indicates that the target node is reached.
+ /// \retval reach Indicates if the target node is reached.
+ /// It should be initially \c false.
+ ///
/// \return The processed node.
///
- /// \warning The queue must not be empty!
+ /// \pre The queue must not be empty.
Node processNextNode(Node target, bool& reach) {
Node n = _list[++_list_front];
_visitor->process(n);
@@ -1433,16 +1497,19 @@
/// \brief Processes the next node.
///
- /// Processes the next node. And checks that at least one of
- /// reached node has true value in the \c nm node map. If one node
- /// with true value is reachable from the processed node then the
- /// rnode parameter will be set to the first of such nodes.
+ /// Processes the next node and checks if at least one of reached
+ /// nodes has \c true value in the \c nm node map. If one node
+ /// with \c true value is reachable from the processed node, then the
+ /// \c rnode parameter will be set to the first of such nodes.
///
- /// \param nm The node map of possible targets.
+ /// \param nm A \c bool (or convertible) node map that indicates the
+ /// possible targets.
/// \retval rnode The reached target node.
+ /// It should be initially \c INVALID.
+ ///
/// \return The processed node.
///
- /// \warning The queue must not be empty!
+ /// \pre The queue must not be empty.
template <typename NM>
Node processNextNode(const NM& nm, Node& rnode) {
Node n = _list[++_list_front];
@@ -1463,44 +1530,71 @@
return n;
}
- /// \brief Next node to be processed.
+ /// \brief The next node to be processed.
///
- /// Next node to be processed.
- ///
- /// \return The next node to be processed or INVALID if the stack is
- /// empty.
- Node nextNode() {
+ /// Returns the next node to be processed or \c INVALID if the queue
+ /// is empty.
+ Node nextNode() const {
return _list_front != _list_back ? _list[_list_front + 1] : INVALID;
}
/// \brief Returns \c false if there are nodes
- /// to be processed in the queue
+ /// to be processed.
///
/// Returns \c false if there are nodes
- /// to be processed in the queue
- bool emptyQueue() { return _list_front == _list_back; }
+ /// to be processed in the queue.
+ bool emptyQueue() const { return _list_front == _list_back; }
/// \brief Returns the number of the nodes to be processed.
///
/// Returns the number of the nodes to be processed in the queue.
- int queueSize() { return _list_back - _list_front; }
+ int queueSize() const { return _list_back - _list_front; }
/// \brief Executes the algorithm.
///
/// Executes the algorithm.
///
- /// \pre init() must be called and at least one node should be added
+ /// 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 (forest),
+ /// - the distance of each node from the root(s).
+ ///
+ /// \pre init() must be called and at least one root node should be added
/// with addSource() before using this function.
+ ///
+ /// \note <tt>b.start()</tt> is just a shortcut of the following code.
+ /// \code
+ /// while ( !b.emptyQueue() ) {
+ /// b.processNextNode();
+ /// }
+ /// \endcode
void start() {
while ( !emptyQueue() ) processNextNode();
}
- /// \brief Executes the algorithm until \c dest is reached.
+ /// \brief Executes the algorithm until the given target node is reached.
///
- /// Executes the algorithm until \c dest is reached.
+ /// Executes the algorithm until the given target node 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).
+ ///
+ /// \pre init() must be called and at least one root node should be
+ /// added with addSource() before using this function.
+ ///
+ /// \note <tt>b.start(t)</tt> is just a shortcut of the following code.
+ /// \code
+ /// bool reach = false;
+ /// while ( !b.emptyQueue() && !reach ) {
+ /// b.processNextNode(t, reach);
+ /// }
+ /// \endcode
void start(Node dest) {
bool reach = false;
while ( !emptyQueue() && !reach ) processNextNode(dest, reach);
@@ -1510,15 +1604,28 @@
///
/// 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.
+ /// This method runs the %BFS algorithm from the root node(s) in
+ /// order to compute the shortest path to a node \c v with
+ /// <tt>nm[v]</tt> true, if such a node can be found.
///
- ///\param nm must be a bool (or convertible) node map. The
- ///algorithm will stop when it reaches a node \c v with
+ /// \param nm must be a bool (or convertible) node map. The
+ /// algorithm will stop when it reaches a node \c v with
/// <tt>nm[v]</tt> true.
///
- ///\return The reached node \c v with <tt>nm[v]</tt> true or
- ///\c INVALID if no such node was found.
+ /// \return The reached node \c v with <tt>nm[v]</tt> true or
+ /// \c INVALID if no such node was found.
+ ///
+ /// \pre init() must be called and at least one root node should be
+ /// added with addSource() before using this function.
+ ///
+ /// \note <tt>b.start(nm)</tt> is just a shortcut of the following code.
+ /// \code
+ /// Node rnode = INVALID;
+ /// while ( !b.emptyQueue() && rnode == INVALID ) {
+ /// b.processNextNode(nm, rnode);
+ /// }
+ /// return rnode;
+ /// \endcode
template <typename NM>
Node start(const NM &nm) {
Node rnode = INVALID;
@@ -1528,10 +1635,16 @@
return rnode;
}
- /// \brief Runs %BFSVisit algorithm from node \c s.
+ /// \brief Runs the algorithm from the given node.
///
- /// This method runs the %BFS algorithm from a root node \c s.
- /// \note b.run(s) is just a shortcut of the following code.
+ /// This method runs the %BFS algorithm from 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 <tt>b.run(s)</tt> is just a shortcut of the following code.
///\code
/// b.init();
/// b.addSource(s);
@@ -1543,19 +1656,21 @@
start();
}
- /// \brief Runs %BFSVisit algorithm to visit all nodes in the digraph.
+ /// \brief Runs the algorithm to visit all nodes in the digraph.
///
/// This method runs the %BFS algorithm in order to
- /// compute the %BFS path to each node. The algorithm computes
- /// - The %BFS tree.
- /// - The distance of each node from the root in the %BFS tree.
+ /// compute the shortest path to each node.
///
- ///\note b.run() is just a shortcut of the following code.
+ /// The algorithm computes
+ /// - the shortest path tree (forest),
+ /// - the distance of each node from the root(s).
+ ///
+ /// \note <tt>b.run(s)</tt> is just a shortcut of the following code.
///\code
/// b.init();
- /// for (NodeIt it(digraph); it != INVALID; ++it) {
- /// if (!b.reached(it)) {
- /// b.addSource(it);
+ /// for (NodeIt n(gr); n != INVALID; ++n) {
+ /// if (!b.reached(n)) {
+ /// b.addSource(n);
/// b.start();
/// }
/// }
@@ -1569,27 +1684,28 @@
}
}
}
+
///@}
/// \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.
+ /// Either \ref lemon::BfsVisit::run() "run()" or
+ /// \ref lemon::BfsVisit::start() "start()" must be called before
+ /// using them.
///@{
- /// \brief Checks if a node is reachable from the root.
+ /// \brief Checks if a node is reachable from the root(s).
///
/// Returns \c true if \c v is reachable from the root(s).
- /// \warning The source nodes are inditated as unreachable.
/// \pre Either \ref run() or \ref start()
/// must be called before using this function.
- ///
bool reached(Node v) { return (*_reached)[v]; }
+
///@}
+
};
} //END OF NAMESPACE LEMON
#endif
-
diff -r 7c67988fca07 -r f1158744a112 lemon/dfs.h
--- a/lemon/dfs.h Wed Jul 30 12:07:48 2008 +0100
+++ b/lemon/dfs.h Mon Aug 04 22:00:36 2008 +0200
@@ -21,19 +21,17 @@
///\ingroup search
///\file
-///\brief Dfs algorithm.
+///\brief DFS algorithm.
#include <lemon/list_graph.h>
#include <lemon/bits/path_dump.h>
#include <lemon/core.h>
#include <lemon/error.h>
+#include <lemon/assert.h>
#include <lemon/maps.h>
-#include <lemon/concept_check.h>
-
namespace lemon {
-
///Default traits class of Dfs class.
///Default traits class of Dfs class.
@@ -41,74 +39,75 @@
template<class GR>
struct DfsDefaultTraits
{
- ///The digraph type the algorithm runs on.
+ ///The type of the digraph the algorithm runs on.
typedef GR Digraph;
- ///\brief The type of the map that stores the last
+
+ ///\brief The type of the map that stores the predecessor
///arcs of the %DFS paths.
///
- ///The type of the map that stores the last
+ ///The type of the map that stores the predecessor
///arcs of the %DFS paths.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///
- typedef typename Digraph::template NodeMap<typename GR::Arc> PredMap;
- ///Instantiates a PredMap.
+ typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
+ ///Instantiates a \ref PredMap.
///This function instantiates a \ref PredMap.
- ///\param G is the digraph, to which we would like to define the PredMap.
+ ///\param g is the digraph, to which we would like to define the
+ ///\ref PredMap.
///\todo The digraph alone may be insufficient to initialize
- static PredMap *createPredMap(const GR &G)
+ static PredMap *createPredMap(const Digraph &g)
{
- return new PredMap(G);
+ return new PredMap(g);
}
///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 concepts::WriteMap "WriteMap" concept.
- ///\todo named parameter to set this type, function to read and write.
+ ///By default it is a NullMap.
typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
- ///Instantiates a ProcessedMap.
+ ///Instantiates a \ref ProcessedMap.
///This function instantiates a \ref ProcessedMap.
///\param g is the digraph, to which
///we would like to define the \ref ProcessedMap
#ifdef DOXYGEN
- static ProcessedMap *createProcessedMap(const GR &g)
+ static ProcessedMap *createProcessedMap(const Digraph &g)
#else
- static ProcessedMap *createProcessedMap(const GR &)
+ static ProcessedMap *createProcessedMap(const Digraph &)
#endif
{
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 concepts::WriteMap "WriteMap" concept.
- ///\todo named parameter to set this type, function to read and write.
+ ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
typedef typename Digraph::template NodeMap<bool> ReachedMap;
- ///Instantiates a ReachedMap.
+ ///Instantiates a \ref ReachedMap.
///This function instantiates a \ref ReachedMap.
- ///\param G is the digraph, to which
+ ///\param g is the digraph, to which
///we would like to define the \ref ReachedMap.
- static ReachedMap *createReachedMap(const GR &G)
+ static ReachedMap *createReachedMap(const Digraph &g)
{
- return new ReachedMap(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.
+ ///The type of the map that stores the distances of the nodes.
+
+ ///The type of the map that stores the distances of the nodes.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///
typedef typename Digraph::template NodeMap<int> DistMap;
- ///Instantiates a DistMap.
+ ///Instantiates a \ref DistMap.
///This function instantiates a \ref DistMap.
- ///\param G is the digraph, to which we would like to define
- ///the \ref DistMap
- static DistMap *createDistMap(const GR &G)
+ ///\param g is the digraph, to which we would like to define the
+ ///\ref DistMap.
+ static DistMap *createDistMap(const Digraph &g)
{
- return new DistMap(G);
+ return new DistMap(g);
}
};
@@ -117,9 +116,13 @@
///\ingroup search
///This class provides an efficient implementation of the %DFS algorithm.
///
- ///\tparam GR The digraph type the algorithm runs on. The default value is
- ///\ref ListDigraph. The value of GR is not used directly by Dfs, it
- ///is only passed to \ref DfsDefaultTraits.
+ ///There is also a \ref dfs() "function type interface" for the DFS
+ ///algorithm, which is convenient in the simplier cases and it can be
+ ///used easier.
+ ///
+ ///\tparam GR The type of the digraph the algorithm runs on.
+ ///The default value is \ref ListDigraph. The value of GR is not used
+ ///directly by \ref Dfs, it is only passed to \ref DfsDefaultTraits.
///\tparam TR Traits class to set various data types used by the algorithm.
///The default traits class is
///\ref DfsDefaultTraits "DfsDefaultTraits<GR>".
@@ -134,12 +137,10 @@
#endif
class Dfs {
public:
- /**
- * \brief \ref Exception for uninitialized parameters.
- *
- * This error represents problems in the initialization
- * of the parameters of the algorithms.
- */
+ ///\ref Exception for uninitialized parameters.
+
+ ///This error represents problems in the initialization of the
+ ///parameters of the algorithm.
class UninitializedParameter : public lemon::UninitializedParameter {
public:
virtual const char* what() const throw() {
@@ -147,52 +148,54 @@
}
};
+ ///The type of the digraph the algorithm runs on.
+ typedef typename TR::Digraph Digraph;
+
+ ///\brief The type of the map that stores the predecessor arcs of the
+ ///DFS paths.
+ typedef typename TR::PredMap PredMap;
+ ///The type of the map that stores the distances of the nodes.
+ typedef typename TR::DistMap DistMap;
+ ///The type of the map that indicates which nodes are reached.
+ typedef typename TR::ReachedMap ReachedMap;
+ ///The type of the map that indicates which nodes are processed.
+ typedef typename TR::ProcessedMap ProcessedMap;
+ ///The type of the paths.
+ typedef PredMapPath<Digraph, PredMap> Path;
+
+ ///The traits class.
typedef TR Traits;
- ///The type of the underlying digraph.
- typedef typename TR::Digraph Digraph;
- ///\e
+
+ private:
+
typedef typename Digraph::Node Node;
- ///\e
typedef typename Digraph::NodeIt NodeIt;
- ///\e
typedef typename Digraph::Arc Arc;
- ///\e
typedef typename Digraph::OutArcIt OutArcIt;
- ///\brief The type of the map that stores the last
- ///arcs of the %DFS paths.
- typedef typename TR::PredMap PredMap;
- ///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 digraph.
+ //Pointer to the underlying digraph.
const Digraph *G;
- ///Pointer to the map of predecessors arcs.
+ //Pointer to the map of predecessor arcs.
PredMap *_pred;
- ///Indicates if \ref _pred is locally allocated (\c true) or not.
+ //Indicates if _pred is locally allocated (true) or not.
bool local_pred;
- ///Pointer to the map of distances.
+ //Pointer to the map of distances.
DistMap *_dist;
- ///Indicates if \ref _dist is locally allocated (\c true) or not.
+ //Indicates if _dist is locally allocated (true) or not.
bool local_dist;
- ///Pointer to the map of reached status of the nodes.
+ //Pointer to the map of reached status of the nodes.
ReachedMap *_reached;
- ///Indicates if \ref _reached is locally allocated (\c true) or not.
+ //Indicates if _reached is locally allocated (true) or not.
bool local_reached;
- ///Pointer to the map of processed status of the nodes.
+ //Pointer to the map of processed status of the nodes.
ProcessedMap *_processed;
- ///Indicates if \ref _processed is locally allocated (\c true) or not.
+ //Indicates if _processed is locally allocated (true) or not.
bool local_processed;
std::vector<typename Digraph::OutArcIt> _stack;
int _stack_head;
///Creates the maps if necessary.
-
///\todo Better memory allocation (instead of new).
void create_maps()
{
@@ -229,22 +232,21 @@
template <class T>
struct DefPredMapTraits : public Traits {
typedef T PredMap;
- static PredMap *createPredMap(const Digraph &G)
+ static PredMap *createPredMap(const Digraph &)
{
throw UninitializedParameter();
}
};
///\brief \ref named-templ-param "Named parameter" for setting
- ///PredMap type
+ ///\ref PredMap type.
///
- ///\ref named-templ-param "Named parameter" for setting PredMap type
- ///
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref PredMap type.
template <class T>
struct DefPredMap : public Dfs<Digraph, DefPredMapTraits<T> > {
typedef Dfs<Digraph, DefPredMapTraits<T> > Create;
};
-
template <class T>
struct DefDistMapTraits : public Traits {
typedef T DistMap;
@@ -254,12 +256,12 @@
}
};
///\brief \ref named-templ-param "Named parameter" for setting
- ///DistMap type
+ ///\ref DistMap type.
///
- ///\ref named-templ-param "Named parameter" for setting DistMap
- ///type
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref DistMap type.
template <class T>
- struct DefDistMap {
+ struct DefDistMap : public Dfs< Digraph, DefDistMapTraits<T> > {
typedef Dfs<Digraph, DefDistMapTraits<T> > Create;
};
@@ -272,10 +274,10 @@
}
};
///\brief \ref named-templ-param "Named parameter" for setting
- ///ReachedMap type
+ ///\ref ReachedMap type.
///
- ///\ref named-templ-param "Named parameter" for setting ReachedMap type
- ///
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref ReachedMap type.
template <class T>
struct DefReachedMap : public Dfs< Digraph, DefReachedMapTraits<T> > {
typedef Dfs< Digraph, DefReachedMapTraits<T> > Create;
@@ -290,10 +292,10 @@
}
};
///\brief \ref named-templ-param "Named parameter" for setting
- ///ProcessedMap type
+ ///\ref ProcessedMap type.
///
- ///\ref named-templ-param "Named parameter" for setting ProcessedMap type
- ///
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref ProcessedMap type.
template <class T>
struct DefProcessedMap : public Dfs< Digraph, DefProcessedMapTraits<T> > {
typedef Dfs< Digraph, DefProcessedMapTraits<T> > Create;
@@ -301,19 +303,19 @@
struct DefDigraphProcessedMapTraits : public Traits {
typedef typename Digraph::template NodeMap<bool> ProcessedMap;
- static ProcessedMap *createProcessedMap(const Digraph &G)
+ static ProcessedMap *createProcessedMap(const Digraph &g)
{
- return new ProcessedMap(G);
+ return new ProcessedMap(g);
}
};
- ///\brief \ref named-templ-param "Named parameter"
- ///for setting the ProcessedMap type to be Digraph::NodeMap<bool>.
+ ///\brief \ref named-templ-param "Named parameter" for setting
+ ///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
///
- ///\ref named-templ-param "Named parameter"
- ///for setting the ProcessedMap type to be Digraph::NodeMap<bool>.
- ///If you don't set it explicitely, it will be automatically allocated.
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
+ ///If you don't set it explicitly, it will be automatically allocated.
template <class T>
- class DefProcessedMapToBeDefaultMap :
+ struct DefProcessedMapToBeDefaultMap :
public Dfs< Digraph, DefDigraphProcessedMapTraits> {
typedef Dfs< Digraph, DefDigraphProcessedMapTraits> Create;
};
@@ -324,10 +326,10 @@
///Constructor.
- ///\param _G the digraph the algorithm will run on.
- ///
- Dfs(const Digraph& _G) :
- G(&_G),
+ ///Constructor.
+ ///\param g The digraph the algorithm runs on.
+ Dfs(const Digraph &g) :
+ G(&g),
_pred(NULL), local_pred(false),
_dist(NULL), local_dist(false),
_reached(NULL), local_reached(false),
@@ -343,11 +345,11 @@
if(local_processed) delete _processed;
}
- ///Sets the map storing the predecessor arcs.
+ ///Sets the map that stores the predecessor arcs.
- ///Sets the map storing the predecessor arcs.
+ ///Sets the map that stores the predecessor arcs.
///If you don't use this function before calling \ref run(),
- ///it will allocate one. The destuctor deallocates this
+ ///it will allocate one. The destructor deallocates this
///automatically allocated map, of course.
///\return <tt> (*this) </tt>
Dfs &predMap(PredMap &m)
@@ -360,11 +362,46 @@
return *this;
}
- ///Sets the map storing the distances calculated by the algorithm.
+ ///Sets the map that indicates which nodes are reached.
- ///Sets the map storing the distances calculated by the algorithm.
+ ///Sets the map that indicates which nodes are reached.
///If you don't use this function before calling \ref run(),
- ///it will allocate one. The destuctor deallocates this
+ ///it will allocate one. The destructor deallocates this
+ ///automatically allocated map, of course.
+ ///\return <tt> (*this) </tt>
+ Dfs &reachedMap(ReachedMap &m)
+ {
+ if(local_reached) {
+ delete _reached;
+ local_reached=false;
+ }
+ _reached = &m;
+ return *this;
+ }
+
+ ///Sets the map that indicates which nodes are processed.
+
+ ///Sets the map that indicates which nodes are processed.
+ ///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 <tt> (*this) </tt>
+ Dfs &processedMap(ProcessedMap &m)
+ {
+ if(local_processed) {
+ delete _processed;
+ local_processed=false;
+ }
+ _processed = &m;
+ return *this;
+ }
+
+ ///Sets the map that stores the distances of the nodes.
+
+ ///Sets the map that stores the distances of the nodes 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 <tt> (*this) </tt>
Dfs &distMap(DistMap &m)
@@ -377,50 +414,17 @@
return *this;
}
- ///Sets the map indicating if a node is reached.
+ public:
- ///Sets the map indicating if a node is reached.
- ///If you don't use this function before calling \ref run(),
- ///it will allocate one. The destuctor deallocates this
- ///automatically allocated map, of course.
- ///\return <tt> (*this) </tt>
- Dfs &reachedMap(ReachedMap &m)
- {
- if(local_reached) {
- delete _reached;
- local_reached=false;
- }
- _reached = &m;
- return *this;
- }
-
- ///Sets the map indicating if a node is processed.
-
- ///Sets the map indicating if a node is processed.
- ///If you don't use this function before calling \ref run(),
- ///it will allocate one. The destuctor deallocates this
- ///automatically allocated map, of course.
- ///\return <tt> (*this) </tt>
- Dfs &processedMap(ProcessedMap &m)
- {
- if(local_processed) {
- delete _processed;
- local_processed=false;
- }
- _processed = &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(...).
+ ///one of the member functions called \ref lemon::Dfs::run() "run()".
///\n
- ///If you need more control on the execution,
- ///first you must call \ref init(), then you can add a source node
- ///with \ref addSource().
- ///Finally \ref start() will perform the actual path
- ///computation.
+ ///If you need more control on the execution, first you must call
+ ///\ref lemon::Dfs::init() "init()", then you can add a source node
+ ///with \ref lemon::Dfs::addSource() "addSource()".
+ ///Finally \ref lemon::Dfs::start() "start()" will perform the
+ ///actual path computation.
///@{
@@ -435,7 +439,6 @@
_stack_head=-1;
for ( NodeIt u(*G) ; u!=INVALID ; ++u ) {
_pred->set(u,INVALID);
- // _predNode->set(u,INVALID);
_reached->set(u,false);
_processed->set(u,false);
}
@@ -445,10 +448,14 @@
///Adds a new source node to the set of nodes to be processed.
///
- ///\warning dists are wrong (or at least strange)
- ///in case of multiple sources.
+ ///\pre The stack must be empty. (Otherwise the algorithm gives
+ ///false results.)
+ ///
+ ///\warning Distances will be wrong (or at least strange) in case of
+ ///multiple sources.
void addSource(Node s)
{
+ LEMON_DEBUG(emptyQueue(), "The stack is not empty.");
if(!(*_reached)[s])
{
_reached->set(s,true);
@@ -471,7 +478,7 @@
///
///\return The processed arc.
///
- ///\pre The stack must not be empty!
+ ///\pre The stack must not be empty.
Arc processNextArc()
{
Node m;
@@ -497,61 +504,68 @@
}
return e;
}
+
///Next arc to be processed.
///Next arc to be processed.
///
- ///\return The next arc to be processed or INVALID if the stack is
- /// empty.
- OutArcIt nextArc()
+ ///\return The next arc to be processed or \c INVALID if the stack
+ ///is empty.
+ OutArcIt nextArc() const
{
return _stack_head>=0?_stack[_stack_head]:INVALID;
}
///\brief Returns \c false if there are nodes
- ///to be processed in the queue
+ ///to be processed.
///
///Returns \c false if there are nodes
- ///to be processed in the queue
- bool emptyQueue() { return _stack_head<0; }
+ ///to be processed in the queue (stack).
+ bool emptyQueue() const { return _stack_head<0; }
+
///Returns the number of the nodes to be processed.
- ///Returns the number of the nodes to be processed in the queue.
- int queueSize() { return _stack_head+1; }
+ ///Returns the number of the nodes to be processed in the queue (stack).
+ int queueSize() const { return _stack_head+1; }
///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 %DFS algorithm from the root node
+ ///in order to compute the DFS path to each node.
///
- ///This method runs the %DFS algorithm from the root node(s)
- ///in order to
- ///compute the
- ///%DFS path to each node. The algorithm computes
- ///- The %DFS tree.
- ///- The distance of each node from the root(s) in the %DFS tree.
+ /// The algorithm computes
+ ///- the %DFS tree,
+ ///- the distance of each node from the root in the %DFS tree.
///
+ ///\pre init() must be called and a root node should be
+ ///added with addSource() before using this function.
+ ///
+ ///\note <tt>d.start()</tt> is just a shortcut of the following code.
+ ///\code
+ /// while ( !d.emptyQueue() ) {
+ /// d.processNextArc();
+ /// }
+ ///\endcode
void start()
{
while ( !emptyQueue() ) processNextArc();
}
- ///Executes the algorithm until \c dest is reached.
+ ///Executes the algorithm until the given target node is reached.
- ///Executes the algorithm until \c dest is reached.
+ ///Executes the algorithm until the given target node 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 %DFS algorithm from the root node
+ ///in order to compute the DFS path to \c dest.
///
- ///This method runs the %DFS algorithm from the root node(s)
- ///in order to
- ///compute the
- ///%DFS path to \c dest. The algorithm computes
- ///- The %DFS path to \c dest.
- ///- The distance of \c dest from the root(s) in the %DFS tree.
+ ///The algorithm computes
+ ///- the %DFS path to \c dest,
+ ///- the distance of \c dest from the root in the %DFS tree.
///
+ ///\pre init() must be called and a root node should be
+ ///added with addSource() before using this function.
void start(Node dest)
{
while ( !emptyQueue() && G->target(_stack[_stack_head])!=dest )
@@ -562,39 +576,86 @@
///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.
+ ///This method runs the %DFS algorithm from the root node
+ ///until an arc \c a with <tt>am[a]</tt> true is found.
///
- ///\param em must be a bool (or convertible) arc map. The algorithm
- ///will stop when it reaches an arc \c e with <tt>em[e]</tt> true.
+ ///\param am A \c bool (or convertible) arc map. The algorithm
+ ///will stop when it reaches an arc \c a with <tt>am[a]</tt> true.
///
- ///\return The reached arc \c e with <tt>em[e]</tt> true or
+ ///\return The reached arc \c a with <tt>am[a]</tt> true or
///\c INVALID if no such arc was found.
///
- ///\warning Contrary to \ref Bfs and \ref Dijkstra, \c em is an arc map,
+ ///\pre init() must be called and a root node should be
+ ///added with addSource() before using this function.
+ ///
+ ///\warning Contrary to \ref Bfs and \ref Dijkstra, \c am is an arc map,
///not a node map.
- template<class EM>
- Arc start(const EM &em)
+ template<class ArcBoolMap>
+ Arc start(const ArcBoolMap &am)
{
- while ( !emptyQueue() && !em[_stack[_stack_head]] )
+ while ( !emptyQueue() && !am[_stack[_stack_head]] )
processNextArc();
return emptyQueue() ? INVALID : _stack[_stack_head];
}
- ///Runs %DFS algorithm to visit all nodes in the digraph.
+ ///Runs the algorithm from the given node.
- ///This method runs the %DFS algorithm in order to
- ///compute the
- ///%DFS path to each node. The algorithm computes
- ///- The %DFS tree.
- ///- The distance of each node from the root in the %DFS tree.
+ ///This method runs the %DFS algorithm from node \c s
+ ///in order to compute the DFS path to each node.
///
- ///\note d.run() is just a shortcut of the following code.
+ ///The algorithm computes
+ ///- the %DFS tree,
+ ///- the distance of each node from the root in the %DFS tree.
+ ///
+ ///\note <tt>d.run(s)</tt> is just a shortcut of the following code.
///\code
/// d.init();
- /// for (NodeIt it(digraph); it != INVALID; ++it) {
- /// if (!d.reached(it)) {
- /// d.addSource(it);
+ /// d.addSource(s);
+ /// d.start();
+ ///\endcode
+ void run(Node s) {
+ init();
+ addSource(s);
+ start();
+ }
+
+ ///Finds the %DFS path between \c s and \c t.
+
+ ///This method runs the %DFS algorithm from node \c s
+ ///in order to compute the DFS path to \c t.
+ ///
+ ///\return The length of the <tt>s</tt>--<tt>t</tt> DFS path,
+ ///if \c t is reachable form \c s, \c 0 otherwise.
+ ///
+ ///\note Apart from the return value, <tt>d.run(s,t)</tt> 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)?_stack_head+1:0;
+ }
+
+ ///Runs the algorithm to visit all nodes in the digraph.
+
+ ///This method runs the %DFS algorithm in order to compute the
+ ///%DFS path to each node.
+ ///
+ ///The algorithm computes
+ ///- the %DFS tree,
+ ///- the distance of each node from the root in the %DFS tree.
+ ///
+ ///\note <tt>d.run()</tt> is just a shortcut of the following code.
+ ///\code
+ /// d.init();
+ /// for (NodeIt n(digraph); n != INVALID; ++n) {
+ /// if (!d.reached(n)) {
+ /// d.addSource(n);
/// d.start();
/// }
/// }
@@ -609,157 +670,124 @@
}
}
- ///Runs %DFS algorithm from node \c s.
-
- ///This method runs the %DFS algorithm from a root node \c s
- ///in order to
- ///compute the
- ///%DFS path to each node. The algorithm computes
- ///- The %DFS tree.
- ///- The distance of each node from the root in the %DFS tree.
- ///
- ///\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 %DFS path between \c s and \c t.
-
- ///Finds the %DFS path between \c s and \c t.
- ///
- ///\return The length of the %DFS s---t path if there exists one,
- ///0 otherwise.
- ///\note Apart from the return value, d.run(s,t) 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)?_stack_head+1:0;
- }
-
///@}
///\name Query Functions
///The result of the %DFS algorithm can be obtained using these
///functions.\n
- ///Before the use of these functions,
- ///either run() or start() must be called.
+ ///Either \ref lemon::Dfs::run() "run()" or \ref lemon::Dfs::start()
+ ///"start()" must be called before using them.
///@{
- typedef PredMapPath<Digraph, PredMap> Path;
+ ///The DFS path to a node.
- ///Gives back the shortest path.
+ ///Returns the DFS path to a node.
+ ///
+ ///\warning \c t should be reachable from the root.
+ ///
+ ///\pre Either \ref run() or \ref start() must be called before
+ ///using this function.
+ Path path(Node t) const { return Path(*G, *_pred, t); }
- ///Gives back the shortest path.
- ///\pre The \c t should be reachable from the source.
- Path path(Node t)
- {
- return Path(*G, *_pred, t);
- }
+ ///The distance of a node from the root.
- ///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 is unreachable from the root(s) then the return
- ///value of this funcion is undefined.
+ ///Returns the distance of a node from the root.
+ ///
+ ///\warning If node \c v is not reachable from the root, then
+ ///the return value of this function is undefined.
+ ///
+ ///\pre Either \ref run() or \ref start() must be called before
+ ///using this function.
int dist(Node v) const { return (*_dist)[v]; }
- ///Returns the 'previous arc' of the %DFS tree.
+ ///Returns the 'previous arc' of the %DFS tree for a node.
- ///For a node \c v it returns the 'previous arc'
- ///of the %DFS path,
- ///i.e. it returns the last arc of a %DFS 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
- ///%DFS tree used here is equal to the %DFS tree used in
+ ///This function returns the 'previous arc' of the %DFS tree for the
+ ///node \c v, i.e. it returns the last arc of a %DFS path from the
+ ///root to \c v. It is \c INVALID
+ ///if \c v is not reachable from the root(s) or if \c v is a root.
+ ///
+ ///The %DFS tree used here is equal to the %DFS tree used in
///\ref predNode().
+ ///
///\pre Either \ref run() or \ref start() must be called before using
///this function.
Arc predArc(Node v) const { return (*_pred)[v];}
///Returns the 'previous node' of the %DFS tree.
- ///For a node \c v it returns the 'previous node'
- ///of the %DFS tree,
- ///i.e. it returns the last but one node from a %DFS path from the
- ///root(s) to \c v.
- ///It is INVALID if \c v is unreachable from the root(s) or
- ///if \c v itself a root.
- ///The %DFS tree used here is equal to the %DFS
- ///tree used in \ref predArc().
+ ///This function returns the 'previous node' of the %DFS
+ ///tree for the node \c v, i.e. it returns the last but one node
+ ///from a %DFS path from the root to \c v. It is \c INVALID
+ ///if \c v is not reachable from the root(s) or if \c v is a root.
+ ///
+ ///The %DFS tree used here is equal to the %DFS tree used in
+ ///\ref predArc().
+ ///
///\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.
+ ///\brief Returns a const reference to the node map that stores the
+ ///distances of the nodes.
+ ///
+ ///Returns a const reference to the node map that stores the
+ ///distances of the nodes calculated by the algorithm.
+ ///
+ ///\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 %DFS arc-tree map.
-
- ///Returns a reference to the NodeMap of the arcs of the
- ///%DFS tree.
+ ///\brief Returns a const reference to the node map that stores the
+ ///predecessor arcs.
+ ///
+ ///Returns a const reference to the node map that stores the predecessor
+ ///arcs, which form the DFS tree.
+ ///
///\pre Either \ref run() or \ref init()
///must be called before using this function.
const PredMap &predMap() const { return *_pred;}
- ///Checks if a node is reachable from the root.
+ ///Checks if a node is reachable from the root(s).
///Returns \c true if \c v is reachable from the root(s).
- ///\warning The source nodes are inditated as unreachable.
///\pre Either \ref run() or \ref start()
///must be called before using this function.
- ///
- bool reached(Node v) { return (*_reached)[v]; }
+ bool reached(Node v) const { return (*_reached)[v]; }
///@}
};
- ///Default traits class of Dfs function.
+ ///Default traits class of dfs() function.
- ///Default traits class of Dfs function.
+ ///Default traits class of dfs() function.
///\tparam GR Digraph type.
template<class GR>
struct DfsWizardDefaultTraits
{
- ///The digraph type the algorithm runs on.
+ ///The type of the digraph the algorithm runs on.
typedef GR Digraph;
- ///\brief The type of the map that stores the last
+
+ ///\brief The type of the map that stores the predecessor
///arcs of the %DFS paths.
///
- ///The type of the map that stores the last
+ ///The type of the map that stores the predecessor
///arcs of the %DFS paths.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
///
- typedef NullMap<typename Digraph::Node,typename GR::Arc> PredMap;
- ///Instantiates a PredMap.
+ typedef NullMap<typename Digraph::Node,typename Digraph::Arc> PredMap;
+ ///Instantiates a \ref PredMap.
///This function instantiates a \ref PredMap.
- ///\param g is the digraph, to which we would like to define the PredMap.
+ ///\param g is the digraph, to which we would like to define the
+ ///\ref PredMap.
///\todo The digraph alone may be insufficient to initialize
#ifdef DOXYGEN
- static PredMap *createPredMap(const GR &g)
+ static PredMap *createPredMap(const Digraph &g)
#else
- static PredMap *createPredMap(const GR &)
+ static PredMap *createPredMap(const Digraph &)
#endif
{
return new PredMap();
@@ -769,63 +797,63 @@
///The type of the map that indicates which nodes are processed.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///\todo named parameter to set this type, function to read and write.
typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
- ///Instantiates a ProcessedMap.
+ ///Instantiates a \ref ProcessedMap.
///This function instantiates a \ref ProcessedMap.
///\param g is the digraph, to which
- ///we would like to define the \ref ProcessedMap
+ ///we would like to define the \ref ProcessedMap.
#ifdef DOXYGEN
- static ProcessedMap *createProcessedMap(const GR &g)
+ static ProcessedMap *createProcessedMap(const Digraph &g)
#else
- static ProcessedMap *createProcessedMap(const GR &)
+ static ProcessedMap *createProcessedMap(const Digraph &)
#endif
{
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 concepts::WriteMap "WriteMap" concept.
- ///\todo named parameter to set this type, function to read and write.
+ ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
typedef typename Digraph::template NodeMap<bool> ReachedMap;
- ///Instantiates a ReachedMap.
+ ///Instantiates a \ref ReachedMap.
///This function instantiates a \ref ReachedMap.
- ///\param G is the digraph, to which
+ ///\param g is the digraph, to which
///we would like to define the \ref ReachedMap.
- static ReachedMap *createReachedMap(const GR &G)
+ static ReachedMap *createReachedMap(const Digraph &g)
{
- return new ReachedMap(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.
+ ///The type of the map that stores the distances of the nodes.
+
+ ///The type of the map that stores the distances of the nodes.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
///
typedef NullMap<typename Digraph::Node,int> DistMap;
- ///Instantiates a DistMap.
+ ///Instantiates a \ref DistMap.
///This function instantiates a \ref DistMap.
///\param g is the digraph, to which we would like to define
///the \ref DistMap
#ifdef DOXYGEN
- static DistMap *createDistMap(const GR &g)
+ static DistMap *createDistMap(const Digraph &g)
#else
- static DistMap *createDistMap(const GR &)
+ static DistMap *createDistMap(const Digraph &)
#endif
{
return new DistMap();
}
};
- /// Default traits used by \ref DfsWizard
+ /// Default traits class used by \ref DfsWizard
/// To make it easier to use Dfs algorithm
- ///we have created a wizard class.
+ /// we have created a wizard class.
/// This \ref DfsWizard class needs default traits,
- ///as well as the \ref Dfs class.
+ /// as well as the \ref Dfs class.
/// The \ref DfsWizardBase is a class to be the default traits of the
/// \ref DfsWizard class.
template<class GR>
@@ -834,20 +862,20 @@
typedef DfsWizardDefaultTraits<GR> Base;
protected:
- /// Type of the nodes in the digraph.
+ //The type of the nodes in the digraph.
typedef typename Base::Digraph::Node Node;
- /// Pointer to the underlying digraph.
+ //Pointer to the digraph the algorithm runs on.
void *_g;
- ///Pointer to the map of reached nodes.
+ //Pointer to the map of reached nodes.
void *_reached;
- ///Pointer to the map of processed nodes.
+ //Pointer to the map of processed nodes.
void *_processed;
- ///Pointer to the map of predecessors arcs.
+ //Pointer to the map of predecessors arcs.
void *_pred;
- ///Pointer to the map of distances.
+ //Pointer to the map of distances.
void *_dist;
- ///Pointer to the source node.
+ //Pointer to the source node.
Node _source;
public:
@@ -856,26 +884,28 @@
/// This constructor does not require parameters, therefore it initiates
/// all of the attributes to default values (0, INVALID).
DfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0),
- _dist(0), _source(INVALID) {}
+ _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
+ /// \param g The digraph the algorithm runs on.
+ /// \param s The source node.
DfsWizardBase(const GR &g, Node s=INVALID) :
_g(reinterpret_cast<void*>(const_cast<GR*>(&g))),
_reached(0), _processed(0), _pred(0), _dist(0), _source(s) {}
};
- /// A class to make the usage of the Dfs algorithm easier
+ /// Auxiliary class for the function type interface of DFS algorithm.
- /// This class is created to make it easier to use the Dfs algorithm.
- /// It uses the functions and features of the plain \ref Dfs,
- /// but it is much simpler to use it.
+ /// This auxiliary class is created to implement the function type
+ /// interface of \ref Dfs algorithm. It uses the functions and features
+ /// of the plain \ref Dfs, but it is much simpler to use it.
+ /// It should only be used through the \ref dfs() function, which makes
+ /// it easier to use the algorithm.
///
/// Simplicity means that the way to change the types defined
/// in the traits class is based on functions that returns the new class
@@ -884,41 +914,37 @@
/// the new class with the modified type comes from
/// the original class by using the ::
/// operator. In the case of \ref DfsWizard only
- /// a function have to be called and it will
+ /// 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 Dfs object, and calls the \ref Dfs::run
- /// method of it.
+ /// It does not have own \ref run() method. When its \ref run() method
+ /// is called, it initiates a plain \ref Dfs object, and calls the
+ /// \ref Dfs::run() method of it.
template<class TR>
class DfsWizard : public TR
{
typedef TR Base;
- ///The type of the underlying digraph.
+ ///The type of the digraph the algorithm runs on.
typedef typename TR::Digraph Digraph;
- //\e
+
typedef typename Digraph::Node Node;
- //\e
typedef typename Digraph::NodeIt NodeIt;
- //\e
typedef typename Digraph::Arc Arc;
- //\e
typedef typename Digraph::OutArcIt OutArcIt;
- ///\brief The type of the map that stores
- ///the reached nodes
+ ///\brief The type of the map that stores the predecessor
+ ///arcs of the shortest paths.
+ typedef typename TR::PredMap PredMap;
+ ///\brief The type of the map that stores the distances of the nodes.
+ typedef typename TR::DistMap DistMap;
+ ///\brief The type of the map that indicates which nodes are reached.
typedef typename TR::ReachedMap ReachedMap;
- ///\brief The type of the map that stores
- ///the processed nodes
+ ///\brief The type of the map that indicates which nodes are processed.
typedef typename TR::ProcessedMap ProcessedMap;
- ///\brief The type of the map that stores the last
- ///arcs of the %DFS paths.
- typedef typename TR::PredMap PredMap;
- ///The type of the map that stores the distances of the nodes.
- typedef typename TR::DistMap DistMap;
public:
+
/// Constructor.
DfsWizard() : TR() {}
@@ -934,10 +960,10 @@
~DfsWizard() {}
- ///Runs Dfs algorithm from a given node.
+ ///Runs DFS algorithm from a source node.
- ///Runs Dfs algorithm from a given node.
- ///The node can be given by the \ref source function.
+ ///Runs DFS algorithm from a source node.
+ ///The node can be given with the \ref source() function.
void run()
{
if(Base::_source==INVALID) throw UninitializedParameter();
@@ -953,9 +979,9 @@
alg.run(Base::_source);
}
- ///Runs Dfs algorithm from the given node.
+ ///Runs DFS algorithm from the given node.
- ///Runs Dfs algorithm from the given node.
+ ///Runs DFS algorithm from the given node.
///\param s is the given source.
void run(Node s)
{
@@ -963,19 +989,27 @@
run();
}
+ /// Sets the source node, from which the Dfs algorithm runs.
+
+ /// Sets the source node, from which the Dfs algorithm runs.
+ /// \param s is the source node.
+ DfsWizard<TR> &source(Node s)
+ {
+ Base::_source=s;
+ return *this;
+ }
+
template<class T>
struct DefPredMapBase : public Base {
typedef T PredMap;
static PredMap *createPredMap(const Digraph &) { return 0; };
DefPredMapBase(const TR &b) : TR(b) {}
};
-
///\brief \ref named-templ-param "Named parameter"
- ///function for setting PredMap type
+ ///for setting \ref PredMap object.
///
- /// \ref named-templ-param "Named parameter"
- ///function for setting PredMap type
- ///
+ ///\ref named-templ-param "Named parameter"
+ ///for setting \ref PredMap object.
template<class T>
DfsWizard<DefPredMapBase<T> > predMap(const T &t)
{
@@ -983,20 +1017,17 @@
return DfsWizard<DefPredMapBase<T> >(*this);
}
-
template<class T>
struct DefReachedMapBase : public Base {
typedef T ReachedMap;
static ReachedMap *createReachedMap(const Digraph &) { return 0; };
DefReachedMapBase(const TR &b) : TR(b) {}
};
-
///\brief \ref named-templ-param "Named parameter"
- ///function for setting ReachedMap
+ ///for setting \ref ReachedMap object.
///
/// \ref named-templ-param "Named parameter"
- ///function for setting ReachedMap
- ///
+ ///for setting \ref ReachedMap object.
template<class T>
DfsWizard<DefReachedMapBase<T> > reachedMap(const T &t)
{
@@ -1004,20 +1035,17 @@
return DfsWizard<DefReachedMapBase<T> >(*this);
}
-
template<class T>
struct DefProcessedMapBase : public Base {
typedef T ProcessedMap;
static ProcessedMap *createProcessedMap(const Digraph &) { return 0; };
DefProcessedMapBase(const TR &b) : TR(b) {}
};
-
///\brief \ref named-templ-param "Named parameter"
- ///function for setting ProcessedMap
+ ///for setting \ref ProcessedMap object.
///
/// \ref named-templ-param "Named parameter"
- ///function for setting ProcessedMap
- ///
+ ///for setting \ref ProcessedMap object.
template<class T>
DfsWizard<DefProcessedMapBase<T> > processedMap(const T &t)
{
@@ -1031,13 +1059,11 @@
static DistMap *createDistMap(const Digraph &) { return 0; };
DefDistMapBase(const TR &b) : TR(b) {}
};
-
///\brief \ref named-templ-param "Named parameter"
- ///function for setting DistMap type
+ ///for setting \ref DistMap object.
///
- /// \ref named-templ-param "Named parameter"
- ///function for setting DistMap type
- ///
+ ///\ref named-templ-param "Named parameter"
+ ///for setting \ref DistMap object.
template<class T>
DfsWizard<DefDistMapBase<T> > distMap(const T &t)
{
@@ -1045,16 +1071,6 @@
return DfsWizard<DefDistMapBase<T> >(*this);
}
- /// Sets the source node, from which the Dfs algorithm runs.
-
- /// Sets the source node, from which the Dfs algorithm runs.
- /// \param s is the source node.
- DfsWizard<TR> &source(Node s)
- {
- Base::_source=s;
- return *this;
- }
-
};
///Function type interface for Dfs algorithm.
@@ -1082,47 +1098,46 @@
}
#ifdef DOXYGEN
- /// \brief Visitor class for dfs.
+ /// \brief Visitor class for DFS.
///
- /// It gives a simple interface for a functional interface for dfs
- /// traversal. The traversal on a linear data structure.
+ /// This class defines the interface of the DfsVisit events, and
+ /// it could be the base of a real visitor class.
template <typename _Digraph>
struct DfsVisitor {
typedef _Digraph Digraph;
typedef typename Digraph::Arc Arc;
typedef typename Digraph::Node Node;
- /// \brief Called when the arc reach a node.
+ /// \brief Called for the source node of the DFS.
///
- /// It is called when the dfs find an arc which target is not
- /// reached yet.
+ /// This function is called for the source node of the DFS.
+ void start(const Node& node) {}
+ /// \brief Called when the source node is leaved.
+ ///
+ /// This function is called when the source node is leaved.
+ void stop(const Node& node) {}
+ /// \brief Called when a node is reached first time.
+ ///
+ /// This function is called when a node is reached first time.
+ void reach(const Node& node) {}
+ /// \brief Called when an arc reaches a new node.
+ ///
+ /// This function is called when the DFS finds an arc whose target node
+ /// is not reached yet.
void discover(const Arc& arc) {}
- /// \brief Called when the node reached first time.
- ///
- /// It is Called when the node reached first time.
- void reach(const Node& node) {}
- /// \brief Called when we step back on an arc.
- ///
- /// It is called when the dfs should step back on the arc.
- void backtrack(const Arc& arc) {}
- /// \brief Called when we step back from the node.
- ///
- /// It is called when we step back from the node.
- void leave(const Node& node) {}
- /// \brief Called when the arc examined but target of the arc
+ /// \brief Called when an arc is examined but its target node is
/// already discovered.
///
- /// It called when the arc examined but the target of the arc
+ /// This function is called when an arc is examined but its target node is
/// already discovered.
void examine(const Arc& arc) {}
- /// \brief Called for the source node of the dfs.
+ /// \brief Called when the DFS steps back from a node.
///
- /// It is called for the source node of the dfs.
- void start(const Node& node) {}
- /// \brief Called when we leave the source node of the dfs.
+ /// This function is called when the DFS steps back from a node.
+ void leave(const Node& node) {}
+ /// \brief Called when the DFS steps back on an arc.
///
- /// It is called when we leave the source node of the dfs.
- void stop(const Node& node) {}
-
+ /// This function is called when the DFS steps back on an arc.
+ void backtrack(const Arc& arc) {}
};
#else
template <typename _Digraph>
@@ -1130,26 +1145,26 @@
typedef _Digraph Digraph;
typedef typename Digraph::Arc Arc;
typedef typename Digraph::Node Node;
- void discover(const Arc&) {}
- void reach(const Node&) {}
- void backtrack(const Arc&) {}
- void leave(const Node&) {}
- void examine(const Arc&) {}
void start(const Node&) {}
void stop(const Node&) {}
+ void reach(const Node&) {}
+ void discover(const Arc&) {}
+ void examine(const Arc&) {}
+ void leave(const Node&) {}
+ void backtrack(const Arc&) {}
template <typename _Visitor>
struct Constraints {
void constraints() {
Arc arc;
Node node;
- visitor.discover(arc);
- visitor.reach(node);
- visitor.backtrack(arc);
- visitor.leave(node);
- visitor.examine(arc);
visitor.start(node);
visitor.stop(arc);
+ visitor.reach(node);
+ visitor.discover(arc);
+ visitor.examine(arc);
+ visitor.leave(node);
+ visitor.backtrack(arc);
}
_Visitor& visitor;
};
@@ -1159,21 +1174,20 @@
/// \brief Default traits class of DfsVisit class.
///
/// Default traits class of DfsVisit class.
- /// \tparam _Digraph Digraph type.
+ /// \tparam _Digraph The type of the digraph the algorithm runs on.
template<class _Digraph>
struct DfsVisitDefaultTraits {
- /// \brief The digraph type the algorithm runs on.
+ /// \brief The type of the digraph the algorithm runs on.
typedef _Digraph Digraph;
/// \brief 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 concepts::WriteMap "WriteMap" concept.
- /// \todo named parameter to set this type, function to read and write.
+ /// It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
typedef typename Digraph::template NodeMap<bool> ReachedMap;
- /// \brief Instantiates a ReachedMap.
+ /// \brief Instantiates a \ref ReachedMap.
///
/// This function instantiates a \ref ReachedMap.
/// \param digraph is the digraph, to which
@@ -1184,31 +1198,30 @@
};
- /// %DFS Visit algorithm class.
-
/// \ingroup search
+ ///
+ /// \brief %DFS algorithm class with visitor interface.
+ ///
/// This class provides an efficient implementation of the %DFS algorithm
/// with visitor interface.
///
/// The %DfsVisit class provides an alternative interface to the Dfs
/// class. It works with callback mechanism, the DfsVisit object calls
- /// on every dfs event the \c Visitor class member functions.
+ /// the member functions of the \c Visitor class on every DFS event.
///
- /// \tparam _Digraph The digraph type the algorithm runs on.
+ /// \tparam _Digraph The type of the digraph the algorithm runs on.
/// The default value is
- /// \ref ListDigraph. The value of _Digraph is not used directly by Dfs, it
- /// is only passed to \ref DfsDefaultTraits.
- /// \tparam _Visitor The Visitor object for the algorithm. The
- /// \ref DfsVisitor "DfsVisitor<_Digraph>" is an empty Visitor which
- /// does not observe the Dfs events. If you want to observe the dfs
- /// events you should implement your own Visitor class.
+ /// \ref ListDigraph. The value of _Digraph is not used directly by
+ /// \ref DfsVisit, it is only passed to \ref DfsVisitDefaultTraits.
+ /// \tparam _Visitor The Visitor type that is used by the algorithm.
+ /// \ref DfsVisitor "DfsVisitor<_Digraph>" is an empty visitor, which
+ /// does not observe the DFS events. If you want to observe the DFS
+ /// events, you should implement your own visitor class.
/// \tparam _Traits Traits class to set various data types used by the
/// algorithm. The default traits class is
/// \ref DfsVisitDefaultTraits "DfsVisitDefaultTraits<_Digraph>".
/// See \ref DfsVisitDefaultTraits for the documentation of
- /// a Dfs visit traits class.
- ///
- /// \author Jacint Szabo, Alpar Juttner and Balazs Dezso
+ /// a DFS visit traits class.
#ifdef DOXYGEN
template <typename _Digraph, typename _Visitor, typename _Traits>
#else
@@ -1222,7 +1235,7 @@
/// \brief \ref Exception for uninitialized parameters.
///
/// This error represents problems in the initialization
- /// of the parameters of the algorithms.
+ /// of the parameters of the algorithm.
class UninitializedParameter : public lemon::UninitializedParameter {
public:
virtual const char* what() const throw()
@@ -1231,13 +1244,16 @@
}
};
+ ///The traits class.
typedef _Traits Traits;
+ ///The type of the digraph the algorithm runs on.
typedef typename Traits::Digraph Digraph;
+ ///The visitor type used by the algorithm.
typedef _Visitor Visitor;
- ///The type of the map indicating which nodes are reached.
+ ///The type of the map that indicates which nodes are reached.
typedef typename Traits::ReachedMap ReachedMap;
private:
@@ -1247,21 +1263,20 @@
typedef typename Digraph::Arc Arc;
typedef typename Digraph::OutArcIt OutArcIt;
- /// Pointer to the underlying digraph.
+ //Pointer to the underlying digraph.
const Digraph *_digraph;
- /// Pointer to the visitor object.
+ //Pointer to the visitor object.
Visitor *_visitor;
- ///Pointer to the map of reached status of the nodes.
+ //Pointer to the map of reached status of the nodes.
ReachedMap *_reached;
- ///Indicates if \ref _reached is locally allocated (\c true) or not.
+ //Indicates if _reached is locally allocated (true) or not.
bool local_reached;
std::vector<typename Digraph::Arc> _stack;
int _stack_head;
- /// \brief Creates the maps if necessary.
- ///
- /// Creates the maps if necessary.
+ ///Creates the maps if necessary.
+ ///\todo Better memory allocation (instead of new).
void create_maps() {
if(!_reached) {
local_reached = true;
@@ -1288,9 +1303,9 @@
}
};
/// \brief \ref named-templ-param "Named parameter" for setting
- /// ReachedMap type
+ /// ReachedMap type.
///
- /// \ref named-templ-param "Named parameter" for setting ReachedMap type
+ /// \ref named-templ-param "Named parameter" for setting ReachedMap type.
template <class T>
struct DefReachedMap : public DfsVisit< Digraph, Visitor,
DefReachedMapTraits<T> > {
@@ -1304,25 +1319,22 @@
///
/// Constructor.
///
- /// \param digraph the digraph the algorithm will run on.
- /// \param visitor The visitor of the algorithm.
- ///
+ /// \param digraph The digraph the algorithm runs on.
+ /// \param visitor The visitor object of the algorithm.
DfsVisit(const Digraph& digraph, Visitor& visitor)
: _digraph(&digraph), _visitor(&visitor),
_reached(0), local_reached(false) {}
/// \brief Destructor.
- ///
- /// Destructor.
~DfsVisit() {
if(local_reached) delete _reached;
}
- /// \brief Sets the map indicating if a node is reached.
+ /// \brief Sets the map that indicates which nodes are reached.
///
- /// Sets the map indicating if a node is reached.
+ /// Sets the map that indicates which nodes are reached.
/// If you don't use this function before calling \ref run(),
- /// it will allocate one. The destuctor deallocates this
+ /// it will allocate one. The destructor deallocates this
/// automatically allocated map, of course.
/// \return <tt> (*this) </tt>
DfsVisit &reachedMap(ReachedMap &m) {
@@ -1335,21 +1347,23 @@
}
public:
+
/// \name Execution control
/// The simplest way to execute the algorithm is to use
- /// one of the member functions called \c run(...).
+ /// one of the member functions called \ref lemon::DfsVisit::run()
+ /// "run()".
/// \n
- /// If you need more control on the execution,
- /// first you must call \ref init(), then you can adda source node
- /// with \ref addSource().
- /// Finally \ref start() will perform the actual path
- /// computation.
+ /// If you need more control on the execution, first you must call
+ /// \ref lemon::DfsVisit::init() "init()", then you can add several
+ /// source nodes with \ref lemon::DfsVisit::addSource() "addSource()".
+ /// Finally \ref lemon::DfsVisit::start() "start()" will perform the
+ /// actual path computation.
/// @{
+
/// \brief Initializes the internal data structures.
///
/// Initializes the internal data structures.
- ///
void init() {
create_maps();
_stack.resize(countNodes(*_digraph));
@@ -1359,10 +1373,18 @@
}
}
- /// \brief Adds a new source node.
+ ///Adds a new source node.
+
+ ///Adds a new source node to the set of nodes to be processed.
///
- /// Adds a new source node to the set of nodes to be processed.
- void addSource(Node s) {
+ ///\pre The stack must be empty. (Otherwise the algorithm gives
+ ///false results.)
+ ///
+ ///\warning Distances will be wrong (or at least strange) in case of
+ ///multiple sources.
+ void addSource(Node s)
+ {
+ LEMON_DEBUG(emptyQueue(), "The stack is not empty.");
if(!(*_reached)[s]) {
_reached->set(s,true);
_visitor->start(s);
@@ -1383,7 +1405,7 @@
///
/// \return The processed arc.
///
- /// \pre The stack must not be empty!
+ /// \pre The stack must not be empty.
Arc processNextArc() {
Arc e = _stack[_stack_head];
Node m = _digraph->target(e);
@@ -1417,37 +1439,58 @@
///
/// \return The next arc to be processed or INVALID if the stack is
/// empty.
- Arc nextArc() {
+ Arc nextArc() const {
return _stack_head >= 0 ? _stack[_stack_head] : INVALID;
}
/// \brief Returns \c false if there are nodes
- /// to be processed in the queue
+ /// to be processed.
///
/// Returns \c false if there are nodes
- /// to be processed in the queue
- bool emptyQueue() { return _stack_head < 0; }
+ /// to be processed in the queue (stack).
+ bool emptyQueue() const { return _stack_head < 0; }
/// \brief Returns the number of the nodes to be processed.
///
- /// Returns the number of the nodes to be processed in the queue.
- int queueSize() { return _stack_head + 1; }
+ /// Returns the number of the nodes to be processed in the queue (stack).
+ int queueSize() const { return _stack_head + 1; }
/// \brief 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 %DFS algorithm from the root node
+ /// in order to compute the %DFS path to each node.
+ ///
+ /// The algorithm computes
+ /// - the %DFS tree,
+ /// - the distance of each node from the root in the %DFS tree.
+ ///
+ /// \pre init() must be called and a root node should be
+ /// added with addSource() before using this function.
+ ///
+ /// \note <tt>d.start()</tt> is just a shortcut of the following code.
+ /// \code
+ /// while ( !d.emptyQueue() ) {
+ /// d.processNextArc();
+ /// }
+ /// \endcode
void start() {
while ( !emptyQueue() ) processNextArc();
}
- /// \brief Executes the algorithm until \c dest is reached.
+ /// \brief Executes the algorithm until the given target node is reached.
///
- /// Executes the algorithm until \c dest is reached.
+ /// Executes the algorithm until the given target node is reached.
///
- /// \pre init() must be called and at least one node should be added
+ /// This method runs the %DFS algorithm from the root node
+ /// in order to compute the DFS path to \c dest.
+ ///
+ /// The algorithm computes
+ /// - the %DFS path to \c dest,
+ /// - the distance of \c dest from the root in the %DFS tree.
+ ///
+ /// \pre init() must be called and a root node should be added
/// with addSource() before using this function.
void start(Node dest) {
while ( !emptyQueue() && _digraph->target(_stack[_stack_head]) != dest )
@@ -1458,28 +1501,37 @@
///
/// Executes the algorithm until a condition is met.
///
- /// \pre init() must be called and at least one node should be added
+ /// This method runs the %DFS algorithm from the root node
+ /// until an arc \c a with <tt>am[a]</tt> true is found.
+ ///
+ /// \param am A \c bool (or convertible) arc map. The algorithm
+ /// will stop when it reaches an arc \c a with <tt>am[a]</tt> true.
+ ///
+ /// \return The reached arc \c a with <tt>am[a]</tt> true or
+ /// \c INVALID if no such arc was found.
+ ///
+ /// \pre init() must be called and a root node should be added
/// with addSource() before using this function.
///
- /// \param em must be a bool (or convertible) arc map. The algorithm
- /// will stop when it reaches an arc \c e with <tt>em[e]</tt> true.
- ///
- ///\return The reached arc \c e with <tt>em[e]</tt> true or
- ///\c INVALID if no such arc was found.
- ///
- /// \warning Contrary to \ref Bfs and \ref Dijkstra, \c em is an arc map,
+ /// \warning Contrary to \ref Bfs and \ref Dijkstra, \c am is an arc map,
/// not a node map.
- template <typename EM>
- Arc start(const EM &em) {
- while ( !emptyQueue() && !em[_stack[_stack_head]] )
+ template <typename AM>
+ Arc start(const AM &am) {
+ while ( !emptyQueue() && !am[_stack[_stack_head]] )
processNextArc();
return emptyQueue() ? INVALID : _stack[_stack_head];
}
- /// \brief Runs %DFSVisit algorithm from node \c s.
+ /// \brief Runs the algorithm from the given node.
///
- /// This method runs the %DFS algorithm from a root node \c s.
- /// \note d.run(s) is just a shortcut of the following code.
+ /// This method runs the %DFS algorithm from node \c s.
+ /// in order to compute the DFS path to each node.
+ ///
+ /// The algorithm computes
+ /// - the %DFS tree,
+ /// - the distance of each node from the root in the %DFS tree.
+ ///
+ /// \note <tt>d.run(s)</tt> is just a shortcut of the following code.
///\code
/// d.init();
/// d.addSource(s);
@@ -1491,22 +1543,46 @@
start();
}
- /// \brief Runs %DFSVisit algorithm to visit all nodes in the digraph.
+ /// \brief Finds the %DFS path between \c s and \c t.
+
+ /// This method runs the %DFS algorithm from node \c s
+ /// in order to compute the DFS path to \c t.
+ ///
+ /// \return The length of the <tt>s</tt>--<tt>t</tt> DFS path,
+ /// if \c t is reachable form \c s, \c 0 otherwise.
+ ///
+ /// \note Apart from the return value, <tt>d.run(s,t)</tt> 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)?_stack_head+1:0;
+ }
+
+ /// \brief Runs the algorithm to visit all nodes in the digraph.
/// This method runs the %DFS algorithm in order to
- /// compute the %DFS path to each node. The algorithm computes
- /// - The %DFS tree.
- /// - The distance of each node from the root in the %DFS tree.
+ /// compute the %DFS path to each node.
///
- ///\note d.run() is just a shortcut of the following code.
+ /// The algorithm computes
+ /// - the %DFS tree,
+ /// - the distance of each node from the root in the %DFS tree.
+ ///
+ /// \note <tt>d.run()</tt> is just a shortcut of the following code.
///\code
- /// d.init();
- /// for (NodeIt it(digraph); it != INVALID; ++it) {
- /// if (!d.reached(it)) {
- /// d.addSource(it);
- /// d.start();
- /// }
- /// }
+ /// d.init();
+ /// for (NodeIt n(digraph); n != INVALID; ++n) {
+ /// if (!d.reached(n)) {
+ /// d.addSource(n);
+ /// d.start();
+ /// }
+ /// }
///\endcode
void run() {
init();
@@ -1517,27 +1593,28 @@
}
}
}
+
///@}
/// \name Query Functions
/// The result of the %DFS algorithm can be obtained using these
/// functions.\n
- /// Before the use of these functions,
- /// either run() or start() must be called.
+ /// Either \ref lemon::DfsVisit::run() "run()" or
+ /// \ref lemon::DfsVisit::start() "start()" must be called before
+ /// using them.
///@{
- /// \brief Checks if a node is reachable from the root.
+
+ /// \brief Checks if a node is reachable from the root(s).
///
/// Returns \c true if \c v is reachable from the root(s).
- /// \warning The source nodes are inditated as unreachable.
/// \pre Either \ref run() or \ref start()
/// must be called before using this function.
- ///
bool reached(Node v) { return (*_reached)[v]; }
+
///@}
+
};
-
} //END OF NAMESPACE LEMON
#endif
-
diff -r 7c67988fca07 -r f1158744a112 lemon/dijkstra.h
--- a/lemon/dijkstra.h Wed Jul 30 12:07:48 2008 +0100
+++ b/lemon/dijkstra.h Mon Aug 04 22:00:36 2008 +0200
@@ -33,10 +33,10 @@
namespace lemon {
- /// \brief Default OperationTraits for the Dijkstra algorithm class.
+ /// \brief Default operation traits for the Dijkstra algorithm class.
///
- /// It defines all computational operations and constants which are
- /// used in the Dijkstra algorithm.
+ /// This operation traits class defines all computational operations and
+ /// constants which are used in the Dijkstra algorithm.
template <typename Value>
struct DijkstraDefaultOperationTraits {
/// \brief Gives back the zero value of the type.
@@ -47,16 +47,19 @@
static Value plus(const Value& left, const Value& right) {
return left + right;
}
- /// \brief Gives back true only if the first value less than the second.
+ /// \brief Gives back true only if the first value is less than the second.
static bool less(const Value& left, const Value& right) {
return left < right;
}
};
- /// \brief Widest path OperationTraits for the Dijkstra algorithm class.
+ /// \brief Widest path operation traits for the Dijkstra algorithm class.
///
- /// It defines all computational operations and constants which are
- /// used in the Dijkstra algorithm for widest path computation.
+ /// This operation traits class defines all computational operations and
+ /// constants which are used in the Dijkstra algorithm for widest path
+ /// computation.
+ ///
+ /// \see DijkstraDefaultOperationTraits
template <typename Value>
struct DijkstraWidestPathOperationTraits {
/// \brief Gives back the maximum value of the type.
@@ -67,7 +70,7 @@
static Value plus(const Value& left, const Value& right) {
return std::min(left, right);
}
- /// \brief Gives back true only if the first value less than the second.
+ /// \brief Gives back true only if the first value is less than the second.
static bool less(const Value& left, const Value& right) {
return left < right;
}
@@ -76,141 +79,145 @@
///Default traits class of Dijkstra class.
///Default traits class of Dijkstra class.
- ///\tparam GR Digraph type.
- ///\tparam LM Type of length map.
+ ///\tparam GR The type of the digraph.
+ ///\tparam LM The type of the length map.
template<class GR, class LM>
struct DijkstraDefaultTraits
{
- ///The digraph type the algorithm runs on.
+ ///The type of the digraph the algorithm runs on.
typedef GR Digraph;
+
///The type of the map that stores the arc lengths.
///The type of the map that stores the arc lengths.
///It must meet the \ref concepts::ReadMap "ReadMap" concept.
typedef LM LengthMap;
- //The type of the length of the arcs.
+ ///The type of the length of the arcs.
typedef typename LM::Value Value;
+
/// Operation traits for Dijkstra algorithm.
- /// It defines the used operation by the algorithm.
+ /// This class defines the operations that are used in the algorithm.
/// \see DijkstraDefaultOperationTraits
typedef DijkstraDefaultOperationTraits<Value> OperationTraits;
- /// The cross reference type used by heap.
+ /// The cross reference type used by the heap.
- /// The cross reference type used by heap.
+ /// The cross reference type used by the heap.
/// Usually it is \c Digraph::NodeMap<int>.
typedef typename Digraph::template NodeMap<int> HeapCrossRef;
- ///Instantiates a HeapCrossRef.
+ ///Instantiates a \ref HeapCrossRef.
- ///This function instantiates a \c HeapCrossRef.
- /// \param G is the digraph, to which we would like to define the
- /// HeapCrossRef.
- static HeapCrossRef *createHeapCrossRef(const GR &G)
+ ///This function instantiates a \ref HeapCrossRef.
+ /// \param g is the digraph, to which we would like to define the
+ /// \ref HeapCrossRef.
+ static HeapCrossRef *createHeapCrossRef(const Digraph &g)
{
- return new HeapCrossRef(G);
+ return new HeapCrossRef(g);
}
- ///The heap type used by Dijkstra algorithm.
+ ///The heap type used by the Dijkstra algorithm.
- ///The heap type used by Dijkstra algorithm.
+ ///The heap type used by the Dijkstra algorithm.
///
///\sa BinHeap
///\sa Dijkstra
typedef BinHeap<typename LM::Value, HeapCrossRef, std::less<Value> > Heap;
+ ///Instantiates a \ref Heap.
- static Heap *createHeap(HeapCrossRef& R)
+ ///This function instantiates a \ref Heap.
+ static Heap *createHeap(HeapCrossRef& r)
{
- return new Heap(R);
+ return new Heap(r);
}
- ///\brief The type of the map that stores the last
+ ///\brief The type of the map that stores the predecessor
///arcs of the shortest paths.
///
- ///The type of the map that stores the last
+ ///The type of the map that stores the predecessor
///arcs of the shortest paths.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///
- typedef typename Digraph::template NodeMap<typename GR::Arc> PredMap;
- ///Instantiates a PredMap.
+ typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
+ ///Instantiates a \ref PredMap.
- ///This function instantiates a \c PredMap.
- ///\param G is the digraph, to which we would like to define the PredMap.
+ ///This function instantiates a \ref PredMap.
+ ///\param g is the digraph, to which we would like to define the
+ ///\ref PredMap.
///\todo The digraph alone may be insufficient for the initialization
- static PredMap *createPredMap(const GR &G)
+ static PredMap *createPredMap(const Digraph &g)
{
- return new PredMap(G);
+ return new PredMap(g);
}
- ///The type of the map that stores whether a nodes is processed.
+ ///The type of the map that indicates which nodes are processed.
- ///The type of the map that stores whether a nodes is processed.
+ ///The type of the map that indicates which nodes are processed.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
///By default it is a NullMap.
///\todo If it is set to a real map,
///Dijkstra::processed() should read this.
- ///\todo named parameter to set this type, function to read and write.
typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
- ///Instantiates a ProcessedMap.
+ ///Instantiates a \ref ProcessedMap.
- ///This function instantiates a \c ProcessedMap.
+ ///This function instantiates a \ref ProcessedMap.
///\param g is the digraph, to which
- ///we would like to define the \c ProcessedMap
+ ///we would like to define the \ref ProcessedMap
#ifdef DOXYGEN
- static ProcessedMap *createProcessedMap(const GR &g)
+ static ProcessedMap *createProcessedMap(const Digraph &g)
#else
- static ProcessedMap *createProcessedMap(const GR &)
+ static ProcessedMap *createProcessedMap(const Digraph &)
#endif
{
return new ProcessedMap();
}
- ///The type of the map that stores the dists of the nodes.
- ///The type of the map that stores the dists of the nodes.
+ ///The type of the map that stores the distances of the nodes.
+
+ ///The type of the map that stores the distances of the nodes.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///
typedef typename Digraph::template NodeMap<typename LM::Value> DistMap;
- ///Instantiates a DistMap.
+ ///Instantiates a \ref DistMap.
///This function instantiates a \ref DistMap.
- ///\param G is the digraph, to which we would like to define
+ ///\param g is the digraph, to which we would like to define
///the \ref DistMap
- static DistMap *createDistMap(const GR &G)
+ static DistMap *createDistMap(const Digraph &g)
{
- return new DistMap(G);
+ return new DistMap(g);
}
};
///%Dijkstra algorithm class.
/// \ingroup shortest_path
- ///This class provides an efficient implementation of %Dijkstra algorithm.
+ ///This class provides an efficient implementation of the %Dijkstra algorithm.
+ ///
///The arc lengths are passed to the algorithm using a
///\ref concepts::ReadMap "ReadMap",
///so it is easy to change it to any kind of length.
- ///
///The type of the length is determined by the
///\ref concepts::ReadMap::Value "Value" of the length map.
- ///
///It is also possible to change the underlying priority heap.
///
- ///\tparam GR The digraph type the algorithm runs on. The default value
- ///is \ref ListDigraph. The value of GR is not used directly by
- ///Dijkstra, it is only passed to \ref DijkstraDefaultTraits.
- ///\tparam LM This read-only ArcMap determines the lengths of the
+ ///There is also a \ref dijkstra() "function type interface" for the
+ ///%Dijkstra algorithm, which is convenient in the simplier cases and
+ ///it can be used easier.
+ ///
+ ///\tparam GR The type of the digraph the algorithm runs on.
+ ///The default value is \ref ListDigraph.
+ ///The value of GR is not used directly by \ref Dijkstra, it is only
+ ///passed to \ref DijkstraDefaultTraits.
+ ///\tparam LM A readable arc map that determines the lengths of the
///arcs. It is read once for each arc, so the map may involve in
- ///relatively time consuming process to compute the arc length if
+ ///relatively time consuming process to compute the arc lengths if
///it is necessary. The default map type is \ref
- ///concepts::Digraph::ArcMap "Digraph::ArcMap<int>". The value
- ///of LM is not used directly by Dijkstra, it is only passed to \ref
- ///DijkstraDefaultTraits.
- ///\tparam TR Traits class to set
- ///various data types used by the algorithm. The default traits
- ///class is \ref DijkstraDefaultTraits
- ///"DijkstraDefaultTraits<GR,LM>". See \ref
- ///DijkstraDefaultTraits for the documentation of a Dijkstra traits
- ///class.
-
+ ///concepts::Digraph::ArcMap "Digraph::ArcMap<int>".
+ ///The value of LM is not used directly by \ref Dijkstra, it is only
+ ///passed to \ref DijkstraDefaultTraits.
+ ///\tparam TR Traits class to set various data types used by the algorithm.
+ ///The default traits class is \ref DijkstraDefaultTraits
+ ///"DijkstraDefaultTraits<GR,LM>". See \ref DijkstraDefaultTraits
+ ///for the documentation of a Dijkstra traits class.
#ifdef DOXYGEN
template <typename GR, typename LM, typename TR>
#else
@@ -220,12 +227,10 @@
#endif
class Dijkstra {
public:
- /**
- * \brief \ref Exception for uninitialized parameters.
- *
- * This error represents problems in the initialization
- * of the parameters of the algorithms.
- */
+ ///\ref Exception for uninitialized parameters.
+
+ ///This error represents problems in the initialization of the
+ ///parameters of the algorithm.
class UninitializedParameter : public lemon::UninitializedParameter {
public:
virtual const char* what() const throw() {
@@ -233,63 +238,65 @@
}
};
- typedef TR Traits;
- ///The type of the underlying digraph.
+ ///The type of the digraph the algorithm runs on.
typedef typename TR::Digraph Digraph;
- ///\e
- typedef typename Digraph::Node Node;
- ///\e
- typedef typename Digraph::NodeIt NodeIt;
- ///\e
- typedef typename Digraph::Arc Arc;
- ///\e
- typedef typename Digraph::OutArcIt OutArcIt;
///The type of the length of the arcs.
typedef typename TR::LengthMap::Value Value;
///The type of the map that stores the arc lengths.
typedef typename TR::LengthMap LengthMap;
- ///\brief The type of the map that stores the last
- ///arcs of the shortest paths.
+ ///\brief The type of the map that stores the predecessor arcs of the
+ ///shortest paths.
typedef typename TR::PredMap PredMap;
- ///The type of the map indicating if a node is processed.
+ ///The type of the map that stores the distances of the nodes.
+ typedef typename TR::DistMap DistMap;
+ ///The type of the map that indicates 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;
+ ///The type of the paths.
+ typedef PredMapPath<Digraph, PredMap> Path;
///The cross reference type used for the current heap.
typedef typename TR::HeapCrossRef HeapCrossRef;
- ///The heap type used by the dijkstra algorithm.
+ ///The heap type used by the algorithm.
typedef typename TR::Heap Heap;
- ///The operation traits.
+ ///The operation traits class.
typedef typename TR::OperationTraits OperationTraits;
+
+ ///The traits class.
+ typedef TR Traits;
+
private:
- /// Pointer to the underlying digraph.
+
+ typedef typename Digraph::Node Node;
+ typedef typename Digraph::NodeIt NodeIt;
+ typedef typename Digraph::Arc Arc;
+ typedef typename Digraph::OutArcIt OutArcIt;
+
+ //Pointer to the underlying digraph.
const Digraph *G;
- /// Pointer to the length map
+ //Pointer to the length map.
const LengthMap *length;
- ///Pointer to the map of predecessors arcs.
+ //Pointer to the map of predecessors arcs.
PredMap *_pred;
- ///Indicates if \ref _pred is locally allocated (\c true) or not.
+ //Indicates if _pred is locally allocated (true) or not.
bool local_pred;
- ///Pointer to the map of distances.
+ //Pointer to the map of distances.
DistMap *_dist;
- ///Indicates if \ref _dist is locally allocated (\c true) or not.
+ //Indicates if _dist is locally allocated (true) or not.
bool local_dist;
- ///Pointer to the map of processed status of the nodes.
+ //Pointer to the map of processed status of the nodes.
ProcessedMap *_processed;
- ///Indicates if \ref _processed is locally allocated (\c true) or not.
+ //Indicates if _processed is locally allocated (true) or not.
bool local_processed;
- ///Pointer to the heap cross references.
+ //Pointer to the heap cross references.
HeapCrossRef *_heap_cross_ref;
- ///Indicates if \ref _heap_cross_ref is locally allocated (\c true) or not.
+ //Indicates if _heap_cross_ref is locally allocated (true) or not.
bool local_heap_cross_ref;
- ///Pointer to the heap.
+ //Pointer to the heap.
Heap *_heap;
- ///Indicates if \ref _heap is locally allocated (\c true) or not.
+ //Indicates if _heap is locally allocated (true) or not.
bool local_heap;
///Creates the maps if necessary.
-
///\todo Better memory allocation (instead of new).
void create_maps()
{
@@ -315,7 +322,7 @@
}
}
- public :
+ public:
typedef Dijkstra Create;
@@ -331,10 +338,11 @@
throw UninitializedParameter();
}
};
- ///\ref named-templ-param "Named parameter" for setting PredMap type
-
- ///\ref named-templ-param "Named parameter" for setting PredMap type
+ ///\brief \ref named-templ-param "Named parameter" for setting
+ ///\ref PredMap type.
///
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref PredMap type.
template <class T>
struct DefPredMap
: public Dijkstra< Digraph, LengthMap, DefPredMapTraits<T> > {
@@ -349,10 +357,11 @@
throw UninitializedParameter();
}
};
- ///\ref named-templ-param "Named parameter" for setting DistMap type
-
- ///\ref named-templ-param "Named parameter" for setting DistMap type
+ ///\brief \ref named-templ-param "Named parameter" for setting
+ ///\ref DistMap type.
///
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref DistMap type.
template <class T>
struct DefDistMap
: public Dijkstra< Digraph, LengthMap, DefDistMapTraits<T> > {
@@ -362,15 +371,16 @@
template <class T>
struct DefProcessedMapTraits : public Traits {
typedef T ProcessedMap;
- static ProcessedMap *createProcessedMap(const Digraph &G)
+ static ProcessedMap *createProcessedMap(const Digraph &)
{
throw UninitializedParameter();
}
};
- ///\ref named-templ-param "Named parameter" for setting ProcessedMap type
-
- ///\ref named-templ-param "Named parameter" for setting ProcessedMap type
+ ///\brief \ref named-templ-param "Named parameter" for setting
+ ///\ref ProcessedMap type.
///
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref ProcessedMap type.
template <class T>
struct DefProcessedMap
: public Dijkstra< Digraph, LengthMap, DefProcessedMapTraits<T> > {
@@ -379,17 +389,17 @@
struct DefDigraphProcessedMapTraits : public Traits {
typedef typename Digraph::template NodeMap<bool> ProcessedMap;
- static ProcessedMap *createProcessedMap(const Digraph &G)
+ static ProcessedMap *createProcessedMap(const Digraph &g)
{
- return new ProcessedMap(G);
+ return new ProcessedMap(g);
}
};
- ///\brief \ref named-templ-param "Named parameter"
- ///for setting the ProcessedMap type to be Digraph::NodeMap<bool>.
+ ///\brief \ref named-templ-param "Named parameter" for setting
+ ///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
///
- ///\ref named-templ-param "Named parameter"
- ///for setting the ProcessedMap type to be Digraph::NodeMap<bool>.
- ///If you don't set it explicitely, it will be automatically allocated.
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
+ ///If you don't set it explicitly, it will be automatically allocated.
template <class T>
struct DefProcessedMapToBeDefaultMap
: public Dijkstra< Digraph, LengthMap, DefDigraphProcessedMapTraits> {
@@ -413,8 +423,7 @@
///heap and cross reference type
///
///\ref named-templ-param "Named parameter" for setting heap and cross
- ///reference type
- ///
+ ///reference type.
template <class H, class CR = typename Digraph::template NodeMap<int> >
struct DefHeap
: public Dijkstra< Digraph, LengthMap, DefHeapTraits<H, CR> > {
@@ -453,10 +462,10 @@
};
/// \brief \ref named-templ-param "Named parameter" for setting
- /// OperationTraits type
+ ///\ref OperationTraits type
///
- /// \ref named-templ-param "Named parameter" for setting OperationTraits
- /// type
+ ///\ref named-templ-param "Named parameter" for setting
+ ///\ref OperationTraits type.
template <class T>
struct DefOperationTraits
: public Dijkstra<Digraph, LengthMap, DefOperationTraitsTraits<T> > {
@@ -466,7 +475,6 @@
///@}
-
protected:
Dijkstra() {}
@@ -475,10 +483,11 @@
///Constructor.
- ///\param _G the digraph the algorithm will run on.
- ///\param _length the length map used by the algorithm.
- Dijkstra(const Digraph& _G, const LengthMap& _length) :
- G(&_G), length(&_length),
+ ///Constructor.
+ ///\param _g The digraph the algorithm runs on.
+ ///\param _length The length map used by the algorithm.
+ Dijkstra(const Digraph& _g, const LengthMap& _length) :
+ G(&_g), length(&_length),
_pred(NULL), local_pred(false),
_dist(NULL), local_dist(false),
_processed(NULL), local_processed(false),
@@ -506,11 +515,11 @@
return *this;
}
- ///Sets the map storing the predecessor arcs.
+ ///Sets the map that stores the predecessor arcs.
- ///Sets the map storing the predecessor arcs.
+ ///Sets the map that stores the predecessor arcs.
///If you don't use this function before calling \ref run(),
- ///it will allocate one. The destuctor deallocates this
+ ///it will allocate one. The destructor deallocates this
///automatically allocated map, of course.
///\return <tt> (*this) </tt>
Dijkstra &predMap(PredMap &m)
@@ -523,11 +532,29 @@
return *this;
}
- ///Sets the map storing the distances calculated by the algorithm.
+ ///Sets the map that indicates which nodes are processed.
- ///Sets the map storing the distances calculated by the algorithm.
+ ///Sets the map that indicates which nodes are processed.
///If you don't use this function before calling \ref run(),
- ///it will allocate one. The destuctor deallocates this
+ ///it will allocate one. The destructor deallocates this
+ ///automatically allocated map, of course.
+ ///\return <tt> (*this) </tt>
+ Dijkstra &processedMap(ProcessedMap &m)
+ {
+ if(local_processed) {
+ delete _processed;
+ local_processed=false;
+ }
+ _processed = &m;
+ return *this;
+ }
+
+ ///Sets the map that stores the distances of the nodes.
+
+ ///Sets the map that stores the distances of the nodes 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 <tt> (*this) </tt>
Dijkstra &distMap(DistMap &m)
@@ -544,7 +571,7 @@
///Sets the heap and the cross reference used by algorithm.
///If you don't use this function before calling \ref run(),
- ///it will allocate one. The destuctor deallocates this
+ ///it will allocate one. The destructor deallocates this
///automatically allocated heap and cross reference, of course.
///\return <tt> (*this) </tt>
Dijkstra &heap(Heap& hp, HeapCrossRef &cr)
@@ -563,6 +590,7 @@
}
private:
+
void finalizeNodeData(Node v,Value dst)
{
_processed->set(v,true);
@@ -571,17 +599,15 @@
public:
- typedef PredMapPath<Digraph, PredMap> Path;
-
///\name Execution control
- ///The simplest way to execute the algorithm is to use
- ///one of the member functions called \c run(...).
+ ///The simplest way to execute the algorithm is to use one of the
+ ///member functions called \ref lemon::Dijkstra::run() "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.
+ ///If you need more control on the execution, first you must call
+ ///\ref lemon::Dijkstra::init() "init()", then you can add several
+ ///source nodes with \ref lemon::Dijkstra::addSource() "addSource()".
+ ///Finally \ref lemon::Dijkstra::start() "start()" will perform the
+ ///actual path computation.
///@{
@@ -603,10 +629,9 @@
///Adds a new source node.
///Adds a new source node to the priority heap.
- ///
///The optional second parameter is the initial distance of the node.
///
- ///It checks if the node has already been added to the heap and
+ ///The function checks if the node has already been added to the heap and
///it is pushed to the heap only if either it was not in the heap
///or the shortest path found till then is shorter than \c dst.
void addSource(Node s,Value dst=OperationTraits::zero())
@@ -625,7 +650,7 @@
///
///\return The processed node.
///
- ///\warning The priority heap must not be empty!
+ ///\warning The priority heap must not be empty.
Node processNextNode()
{
Node v=_heap->top();
@@ -656,62 +681,66 @@
return v;
}
- ///Next node to be processed.
+ ///The next node to be processed.
- ///Next node to be processed.
- ///
- ///\return The next node to be processed or INVALID if the priority heap
- /// is empty.
- Node nextNode()
+ ///Returns the next node to be processed or \c INVALID if the
+ ///priority heap is empty.
+ Node nextNode() const
{
return !_heap->empty()?_heap->top():INVALID;
}
///\brief Returns \c false if there are nodes
- ///to be processed in the priority heap
+ ///to be processed.
///
///Returns \c false if there are nodes
- ///to be processed in the priority heap
- bool emptyQueue() { return _heap->empty(); }
+ ///to be processed in the priority heap.
+ bool emptyQueue() const { return _heap->empty(); }
+
///Returns the number of the nodes to be processed in the priority heap
- ///Returns the number of the nodes to be processed in the priority heap
+ ///Returns the number of the nodes to be processed in the priority heap.
///
- int queueSize() { return _heap->size(); }
+ int queueSize() const { return _heap->size(); }
///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 %Dijkstra algorithm from the root node(s)
+ ///in order to compute the shortest path to each node.
+ ///
+ ///The algorithm computes
+ ///- the shortest path tree (forest),
+ ///- the distance of each node from the root(s).
+ ///
+ ///\pre init() must be called and at least one root node should be
+ ///added with addSource() before using this function.
+ ///
+ ///\note <tt>d.start()</tt> is just a shortcut of the following code.
+ ///\code
+ /// while ( !d.emptyQueue() ) {
+ /// d.processNextNode();
+ /// }
+ ///\endcode
+ void start()
+ {
+ while ( !emptyQueue() ) processNextNode();
+ }
+
+ ///Executes the algorithm until the given target node is reached.
+
+ ///Executes the algorithm until the given target node is reached.
///
///This method runs the %Dijkstra 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).
+ ///in order to compute the shortest path to \c dest.
///
- void start()
- {
- while ( !_heap->empty() ) processNextNode();
- }
-
- ///Executes the algorithm until \c dest is reached.
-
- ///Executes the algorithm until \c dest is reached.
+ ///The algorithm computes
+ ///- the shortest path to \c dest,
+ ///- the distance of \c dest from the root(s).
///
- ///\pre init() must be called and at least one node should be added
- ///with addSource() before using this function.
- ///
- ///This method runs the %Dijkstra 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).
- ///
+ ///\pre init() must be called and at least one root node should be
+ ///added with addSource() before using this function.
void start(Node dest)
{
while ( !_heap->empty() && _heap->top()!=dest ) processNextNode();
@@ -722,14 +751,18 @@
///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.
+ ///This method runs the %Dijkstra algorithm from the root node(s) in
+ ///order to compute the shortest path to a node \c v with
+ /// <tt>nm[v]</tt> true, if such a node can be found.
///
- ///\param nm must be a bool (or convertible) node map. The algorithm
+ ///\param nm A \c bool (or convertible) node map. The algorithm
///will stop when it reaches a node \c v with <tt>nm[v]</tt> true.
///
///\return The reached node \c v with <tt>nm[v]</tt> true or
///\c INVALID if no such node was found.
+ ///
+ ///\pre init() must be called and at least one root node should be
+ ///added with addSource() before using this function.
template<class NodeBoolMap>
Node start(const NodeBoolMap &nm)
{
@@ -739,16 +772,16 @@
return _heap->top();
}
- ///Runs %Dijkstra algorithm from node \c s.
+ ///Runs the algorithm from the given node.
- ///This method runs the %Dijkstra 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.
+ ///This method runs the %Dijkstra algorithm from node \c s
+ ///in order to compute the shortest path to each node.
///
- ///\note d.run(s) is just a shortcut of the following code.
+ ///The algorithm computes
+ ///- the shortest path tree,
+ ///- the distance of each node from the root.
+ ///
+ ///\note <tt>d.run(s)</tt> is just a shortcut of the following code.
///\code
/// d.init();
/// d.addSource(s);
@@ -762,12 +795,14 @@
///Finds the shortest path between \c s and \c t.
- ///Finds the shortest path between \c s and \c t.
+ ///This method runs the %Dijkstra algorithm from node \c s
+ ///in order to compute the shortest path to \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.
+ ///\return The length of the shortest <tt>s</tt>--<tt>t</tt> path,
+ ///if \c t is reachable form \c s, \c 0 otherwise.
+ ///
+ ///\note Apart from the return value, <tt>d.run(s,t)</tt> is just a
+ ///shortcut of the following code.
///\code
/// d.init();
/// d.addSource(s);
@@ -785,241 +820,262 @@
///\name Query Functions
///The result of the %Dijkstra algorithm can be obtained using these
///functions.\n
- ///Before the use of these functions,
- ///either run() or start() must be called.
+ ///Either \ref lemon::Dijkstra::run() "run()" or
+ ///\ref lemon::Dijkstra::start() "start()" must be called before
+ ///using them.
///@{
- ///Gives back the shortest path.
+ ///The shortest path to a node.
- ///Gives back the shortest path.
- ///\pre The \c t should be reachable from the source.
- Path path(Node t)
- {
- return Path(*G, *_pred, t);
- }
+ ///Returns the shortest path to a node.
+ ///
+ ///\warning \c t should be reachable from the root(s).
+ ///
+ ///\pre Either \ref run() or \ref start() must be called before
+ ///using this function.
+ Path path(Node t) const { return Path(*G, *_pred, t); }
- ///The distance of a node from the root.
+ ///The distance of a node from the root(s).
- ///Returns the distance of a node from the root.
- ///\pre \ref run() must be called before using this function.
- ///\warning If node \c v in unreachable from the root the return value
- ///of this funcion is undefined.
+ ///Returns the distance of a node from the root(s).
+ ///
+ ///\warning If node \c v is not reachable from the root(s), then
+ ///the return value of this function is undefined.
+ ///
+ ///\pre Either \ref run() or \ref start() must be called before
+ ///using this function.
Value dist(Node v) const { return (*_dist)[v]; }
- ///The current distance of a node from the root.
+ ///Returns the 'previous arc' of the shortest path tree for a node.
- ///Returns the current distance of a node from the root.
- ///It may be decreased in the following processes.
- ///\pre \c node should be reached but not processed
- Value currentDist(Node v) const { return (*_heap)[v]; }
-
- ///Returns the 'previous arc' of the shortest path tree.
-
- ///For a node \c v it returns the 'previous arc' of the shortest path tree,
- ///i.e. it returns the last arc of a shortest path from the root to \c
- ///v. It is \ref INVALID
- ///if \c v is unreachable from the root or if \c v=s. The
- ///shortest path tree used here is equal to the shortest path tree used in
- ///\ref predNode(). \pre \ref run() must be called before using
- ///this function.
+ ///This function returns the 'previous arc' of the shortest path
+ ///tree for the node \c v, i.e. it returns the last arc of a
+ ///shortest path from the root(s) to \c v. It is \c INVALID if \c v
+ ///is not reachable from the root(s) or if \c v is a root.
+ ///
+ ///The shortest path tree used here is equal to the shortest path
+ ///tree used in \ref predNode().
+ ///
+ ///\pre Either \ref run() or \ref start() must be called before
+ ///using this function.
Arc predArc(Node v) const { return (*_pred)[v]; }
- ///Returns the 'previous node' of the shortest path tree.
+ ///Returns the 'previous node' of the shortest path tree for a node.
- ///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 to \c /v. It is INVALID if \c v is unreachable from the root or if
- ///\c v=s. The shortest path tree used here is equal to the shortest path
- ///tree used in \ref predArc(). \pre \ref run() must be called before
+ ///This function returns the 'previous node' of the shortest path
+ ///tree for the node \c v, i.e. it returns the last but one node
+ ///from a shortest path from the root(s) to \c v. It is \c INVALID
+ ///if \c v is not reachable from the root(s) or if \c v is a root.
+ ///
+ ///The shortest path tree used here is equal to the shortest path
+ ///tree used in \ref predArc().
+ ///
+ ///\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 \ref run() must
- ///be called before using this function.
+ ///\brief Returns a const reference to the node map that stores the
+ ///distances of the nodes.
+ ///
+ ///Returns a const reference to the node map that stores the distances
+ ///of the nodes calculated by the algorithm.
+ ///
+ ///\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 arcs of the
- ///shortest path tree.
- ///\pre \ref run() must be called before using this function.
+ ///\brief Returns a const reference to the node map that stores the
+ ///predecessor arcs.
+ ///
+ ///Returns a const reference to the node map that stores the predecessor
+ ///arcs, which form the shortest path tree.
+ ///
+ ///\pre Either \ref run() or \ref init()
+ ///must be called before using this function.
const PredMap &predMap() const { return *_pred;}
- ///Checks if a node is reachable from the root.
+ ///Checks if a node is reachable from the root(s).
- ///Returns \c true if \c v is reachable from the root.
- ///\warning The source nodes are inditated as unreached.
- ///\pre \ref run() must be called before using this function.
- ///
- bool reached(Node v) { return (*_heap_cross_ref)[v] != Heap::PRE_HEAP; }
+ ///Returns \c true if \c v is reachable from the root(s).
+ ///\pre Either \ref run() or \ref start()
+ ///must be called before using this function.
+ bool reached(Node v) const { return (*_heap_cross_ref)[v] !=
+ Heap::PRE_HEAP; }
///Checks if a node is processed.
///Returns \c true if \c v is processed, i.e. the shortest
///path to \c v has already found.
- ///\pre \ref run() must be called before using this function.
- ///
- bool processed(Node v) { return (*_heap_cross_ref)[v] == Heap::POST_HEAP; }
+ ///\pre Either \ref run() or \ref start()
+ ///must be called before using this function.
+ bool processed(Node v) const { return (*_heap_cross_ref)[v] ==
+ Heap::POST_HEAP; }
+
+ ///The current distance of a node from the root(s).
+
+ ///Returns the current distance of a node from the root(s).
+ ///It may be decreased in the following processes.
+ ///\pre \c v should be reached but not processed.
+ Value currentDist(Node v) const { return (*_heap)[v]; }
///@}
};
+ ///Default traits class of dijkstra() function.
-
-
- ///Default traits class of Dijkstra function.
-
- ///Default traits class of Dijkstra function.
- ///\tparam GR Digraph type.
- ///\tparam LM Type of length map.
+ ///Default traits class of dijkstra() function.
+ ///\tparam GR The type of the digraph.
+ ///\tparam LM The type of the length map.
template<class GR, class LM>
struct DijkstraWizardDefaultTraits
{
- ///The digraph type the algorithm runs on.
+ ///The type of the digraph the algorithm runs on.
typedef GR Digraph;
///The type of the map that stores the arc lengths.
///The type of the map that stores the arc lengths.
///It must meet the \ref concepts::ReadMap "ReadMap" concept.
typedef LM LengthMap;
- //The type of the length of the arcs.
+ ///The type of the length of the arcs.
typedef typename LM::Value Value;
+
/// Operation traits for Dijkstra algorithm.
- /// It defines the used operation by the algorithm.
+ /// This class defines the operations that are used in the algorithm.
/// \see DijkstraDefaultOperationTraits
typedef DijkstraDefaultOperationTraits<Value> OperationTraits;
- ///The heap type used by Dijkstra algorithm.
- /// The cross reference type used by heap.
+ /// The cross reference type used by the heap.
- /// The cross reference type used by heap.
+ /// The cross reference type used by the heap.
/// Usually it is \c Digraph::NodeMap<int>.
typedef typename Digraph::template NodeMap<int> HeapCrossRef;
- ///Instantiates a HeapCrossRef.
+ ///Instantiates a \ref HeapCrossRef.
///This function instantiates a \ref HeapCrossRef.
- /// \param G is the digraph, to which we would like to define the
+ /// \param g is the digraph, to which we would like to define the
/// HeapCrossRef.
/// \todo The digraph alone may be insufficient for the initialization
- static HeapCrossRef *createHeapCrossRef(const GR &G)
+ static HeapCrossRef *createHeapCrossRef(const Digraph &g)
{
- return new HeapCrossRef(G);
+ return new HeapCrossRef(g);
}
- ///The heap type used by Dijkstra algorithm.
+ ///The heap type used by the Dijkstra algorithm.
- ///The heap type used by Dijkstra algorithm.
+ ///The heap type used by the Dijkstra algorithm.
///
///\sa BinHeap
///\sa Dijkstra
- typedef BinHeap<typename LM::Value, typename GR::template NodeMap<int>,
+ typedef BinHeap<Value, typename Digraph::template NodeMap<int>,
std::less<Value> > Heap;
- static Heap *createHeap(HeapCrossRef& R)
+ ///Instantiates a \ref Heap.
+
+ ///This function instantiates a \ref Heap.
+ /// \param r is the HeapCrossRef which is used.
+ static Heap *createHeap(HeapCrossRef& r)
{
- return new Heap(R);
+ return new Heap(r);
}
- ///\brief The type of the map that stores the last
+ ///\brief The type of the map that stores the predecessor
///arcs of the shortest paths.
///
- ///The type of the map that stores the last
+ ///The type of the map that stores the predecessor
///arcs of the shortest paths.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///
- typedef NullMap <typename GR::Node,typename GR::Arc> PredMap;
- ///Instantiates a PredMap.
+ typedef NullMap <typename Digraph::Node,typename Digraph::Arc> PredMap;
+ ///Instantiates a \ref PredMap.
///This function instantiates a \ref PredMap.
- ///\param g is the digraph, to which we would like to define the PredMap.
- ///\todo The digraph alone may be insufficient for the initialization
+ ///\param g is the digraph, to which we would like to define the
+ ///\ref PredMap.
+ ///\todo The digraph alone may be insufficient to initialize
#ifdef DOXYGEN
- static PredMap *createPredMap(const GR &g)
+ static PredMap *createPredMap(const Digraph &g)
#else
- static PredMap *createPredMap(const GR &)
+ static PredMap *createPredMap(const Digraph &)
#endif
{
return new PredMap();
}
- ///The type of the map that stores whether a nodes is processed.
- ///The type of the map that stores whether a nodes is processed.
+ ///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 concepts::WriteMap "WriteMap" concept.
///By default it is a NullMap.
///\todo If it is set to a real map,
///Dijkstra::processed() should read this.
///\todo named parameter to set this type, function to read and write.
typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
- ///Instantiates a ProcessedMap.
+ ///Instantiates a \ref ProcessedMap.
///This function instantiates a \ref ProcessedMap.
///\param g is the digraph, to which
- ///we would like to define the \ref ProcessedMap
+ ///we would like to define the \ref ProcessedMap.
#ifdef DOXYGEN
- static ProcessedMap *createProcessedMap(const GR &g)
+ static ProcessedMap *createProcessedMap(const Digraph &g)
#else
- static ProcessedMap *createProcessedMap(const GR &)
+ static ProcessedMap *createProcessedMap(const Digraph &)
#endif
{
return new ProcessedMap();
}
- ///The type of the map that stores the dists of the nodes.
- ///The type of the map that stores the dists of the nodes.
+ ///The type of the map that stores the distances of the nodes.
+
+ ///The type of the map that stores the distances of the nodes.
///It must meet the \ref concepts::WriteMap "WriteMap" concept.
- ///
- typedef NullMap<typename Digraph::Node,typename LM::Value> DistMap;
- ///Instantiates a DistMap.
+ typedef NullMap<typename Digraph::Node,Value> DistMap;
+ ///Instantiates a \ref DistMap.
///This function instantiates a \ref DistMap.
///\param g is the digraph, to which we would like to define
///the \ref DistMap
#ifdef DOXYGEN
- static DistMap *createDistMap(const GR &g)
+ static DistMap *createDistMap(const Digraph &g)
#else
- static DistMap *createDistMap(const GR &)
+ static DistMap *createDistMap(const Digraph &)
#endif
{
return new DistMap();
}
};
- /// Default traits used by \ref DijkstraWizard
+ /// Default traits class used by \ref DijkstraWizard
/// To make it easier to use Dijkstra algorithm
- ///we have created a wizard class.
+ /// we have created a wizard class.
/// This \ref DijkstraWizard class needs default traits,
- ///as well as the \ref Dijkstra class.
+ /// as well as the \ref Dijkstra class.
/// The \ref DijkstraWizardBase is a class to be the default traits of the
/// \ref DijkstraWizard class.
/// \todo More named parameters are required...
template<class GR,class LM>
class DijkstraWizardBase : public DijkstraWizardDefaultTraits<GR,LM>
{
-
typedef DijkstraWizardDefaultTraits<GR,LM> Base;
protected:
- /// Type of the nodes in the digraph.
+ //The type of the nodes in the digraph.
typedef typename Base::Digraph::Node Node;
- /// Pointer to the underlying digraph.
+ //Pointer to the digraph the algorithm runs on.
void *_g;
- /// Pointer to the length map
+ //Pointer to the length map
void *_length;
- ///Pointer to the map of predecessors arcs.
+ //Pointer to the map of predecessors arcs.
void *_pred;
- ///Pointer to the map of distances.
+ //Pointer to the map of distances.
void *_dist;
- ///Pointer to the source node.
+ //Pointer to the source node.
Node _source;
- public:
+ public:
/// Constructor.
/// This constructor does not require parameters, therefore it initiates
@@ -1032,9 +1088,9 @@
/// 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 l is the initial value of \ref _length
- /// \param s is the initial value of \ref _source
+ /// \param g The digraph the algorithm runs on.
+ /// \param l The length map.
+ /// \param s The source node.
DijkstraWizardBase(const GR &g,const LM &l, Node s=INVALID) :
_g(reinterpret_cast<void*>(const_cast<GR*>(&g))),
_length(reinterpret_cast<void*>(const_cast<LM*>(&l))),
@@ -1042,11 +1098,13 @@
};
- /// A class to make the usage of Dijkstra algorithm easier
+ /// Auxiliary class for the function type interface of Dijkstra algorithm.
- /// This class is created to make it easier to use Dijkstra algorithm.
- /// It uses the functions and features of the plain \ref Dijkstra,
- /// but it is much simpler to use it.
+ /// This auxiliary class is created to implement the function type
+ /// interface of \ref Dijkstra algorithm. It uses the functions and features
+ /// of the plain \ref Dijkstra, but it is much simpler to use it.
+ /// It should only be used through the \ref dijkstra() function, which makes
+ /// it easier to use the algorithm.
///
/// Simplicity means that the way to change the types defined
/// in the traits class is based on functions that returns the new class
@@ -1055,40 +1113,41 @@
/// the new class with the modified type comes from
/// the original class by using the ::
/// operator. In the case of \ref DijkstraWizard only
- /// a function have to be called and it will
+ /// 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 Dijkstra class, and calls the \ref
- /// Dijkstra::run method of it.
+ /// It does not have own \ref run() method. When its \ref run() method
+ /// is called, it initiates a plain \ref Dijkstra object, and calls the
+ /// \ref Dijkstra::run() method of it.
template<class TR>
class DijkstraWizard : public TR
{
typedef TR Base;
- ///The type of the underlying digraph.
+ ///The type of the digraph the algorithm runs on.
typedef typename TR::Digraph Digraph;
- //\e
+
typedef typename Digraph::Node Node;
- //\e
typedef typename Digraph::NodeIt NodeIt;
- //\e
typedef typename Digraph::Arc Arc;
- //\e
typedef typename Digraph::OutArcIt OutArcIt;
///The type of the map that stores the arc lengths.
typedef typename TR::LengthMap LengthMap;
///The type of the length of the arcs.
typedef typename LengthMap::Value Value;
- ///\brief The type of the map that stores the last
+ ///\brief The type of the map that stores the predecessor
///arcs of the shortest paths.
typedef typename TR::PredMap PredMap;
- ///The type of the map that stores the dists of the nodes.
+ ///The type of the map that stores the distances of the nodes.
typedef typename TR::DistMap DistMap;
+ ///The type of the map that indicates which nodes are processed.
+ typedef typename TR::ProcessedMap ProcessedMap;
///The heap type used by the dijkstra algorithm.
typedef typename TR::Heap Heap;
+
public:
+
/// Constructor.
DijkstraWizard() : TR() {}
@@ -1104,10 +1163,10 @@
~DijkstraWizard() {}
- ///Runs Dijkstra algorithm from a given node.
+ ///Runs Dijkstra algorithm from a source node.
- ///Runs Dijkstra algorithm from a given node.
- ///The node can be given by the \ref source function.
+ ///Runs Dijkstra algorithm from a source node.
+ ///The node can be given with the \ref source() function.
void run()
{
if(Base::_source==INVALID) throw UninitializedParameter();
@@ -1129,19 +1188,27 @@
run();
}
+ /// Sets the source node, from which the Dijkstra algorithm runs.
+
+ /// Sets the source node, from which the Dijkstra algorithm runs.
+ /// \param s is the source node.
+ DijkstraWizard<TR> &source(Node s)
+ {
+ Base::_source=s;
+ return *this;
+ }
+
template<class T>
struct DefPredMapBase : public Base {
typedef T PredMap;
static PredMap *createPredMap(const Digraph &) { return 0; };
DefPredMapBase(const TR &b) : TR(b) {}
};
-
///\brief \ref named-templ-param "Named parameter"
- ///function for setting PredMap type
+ ///for setting \ref PredMap object.
///
- /// \ref named-templ-param "Named parameter"
- ///function for setting PredMap type
- ///
+ ///\ref named-templ-param "Named parameter"
+ ///for setting \ref PredMap object.
template<class T>
DijkstraWizard<DefPredMapBase<T> > predMap(const T &t)
{
@@ -1150,18 +1217,34 @@
}
template<class T>
+ struct DefProcessedMapBase : public Base {
+ typedef T ProcessedMap;
+ static ProcessedMap *createProcessedMap(const Digraph &) { return 0; };
+ DefProcessedMapBase(const TR &b) : TR(b) {}
+ };
+ ///\brief \ref named-templ-param "Named parameter"
+ ///for setting \ref ProcessedMap object.
+ ///
+ /// \ref named-templ-param "Named parameter"
+ ///for setting \ref ProcessedMap object.
+ template<class T>
+ DijkstraWizard<DefProcessedMapBase<T> > processedMap(const T &t)
+ {
+ Base::_processed=reinterpret_cast<void*>(const_cast<T*>(&t));
+ return DijkstraWizard<DefProcessedMapBase<T> >(*this);
+ }
+
+ template<class T>
struct DefDistMapBase : public Base {
typedef T DistMap;
static DistMap *createDistMap(const Digraph &) { return 0; };
DefDistMapBase(const TR &b) : TR(b) {}
};
-
///\brief \ref named-templ-param "Named parameter"
- ///function for setting DistMap type
+ ///for setting \ref DistMap object.
///
- /// \ref named-templ-param "Named parameter"
- ///function for setting DistMap type
- ///
+ ///\ref named-templ-param "Named parameter"
+ ///for setting \ref DistMap object.
template<class T>
DijkstraWizard<DefDistMapBase<T> > distMap(const T &t)
{
@@ -1169,16 +1252,6 @@
return DijkstraWizard<DefDistMapBase<T> >(*this);
}
- /// Sets the source node, from which the Dijkstra algorithm runs.
-
- /// Sets the source node, from which the Dijkstra algorithm runs.
- /// \param s is the source node.
- DijkstraWizard<TR> &source(Node s)
- {
- Base::_source=s;
- return *this;
- }
-
};
///Function type interface for Dijkstra algorithm.