[Lemon-commits] Alpar Juttner: Merge
Lemon HG
hg at lemon.cs.elte.hu
Mon Aug 31 08:38:24 CEST 2009
details: http://lemon.cs.elte.hu/hg/lemon/rev/6f7c1052d260
changeset: 753:6f7c1052d260
user: Alpar Juttner <alpar [at] cs.elte.hu>
date: Mon Aug 31 08:32:25 2009 +0200
description:
Merge
diffstat:
lemon/Makefile.am | 1 +
lemon/bellman_ford.h | 1100 +++++++++++++++++++++++++++++++++++++++++++++++
test/CMakeLists.txt | 1 +
test/Makefile.am | 2 +
test/bellman_ford_test.cc | 283 ++++++++++++
5 files changed, 1387 insertions(+), 0 deletions(-)
diffs (truncated from 1434 to 300 lines):
diff --git a/lemon/Makefile.am b/lemon/Makefile.am
--- a/lemon/Makefile.am
+++ b/lemon/Makefile.am
@@ -57,6 +57,7 @@
lemon/adaptors.h \
lemon/arg_parser.h \
lemon/assert.h \
+ lemon/bellman_ford.h \
lemon/bfs.h \
lemon/bin_heap.h \
lemon/bucket_heap.h \
diff --git a/lemon/bellman_ford.h b/lemon/bellman_ford.h
new file mode 100644
--- /dev/null
+++ b/lemon/bellman_ford.h
@@ -0,0 +1,1100 @@
+/* -*- C++ -*-
+ *
+ * This file is a part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2003-2008
+ * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Research Group on Combinatorial Optimization, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#ifndef LEMON_BELLMAN_FORD_H
+#define LEMON_BELLMAN_FORD_H
+
+/// \ingroup shortest_path
+/// \file
+/// \brief Bellman-Ford algorithm.
+
+#include <lemon/bits/path_dump.h>
+#include <lemon/core.h>
+#include <lemon/error.h>
+#include <lemon/maps.h>
+#include <lemon/path.h>
+
+#include <limits>
+
+namespace lemon {
+
+ /// \brief Default OperationTraits for the BellmanFord algorithm class.
+ ///
+ /// This operation traits class defines all computational operations
+ /// and constants that are used in the Bellman-Ford algorithm.
+ /// The default implementation is based on the \c numeric_limits class.
+ /// If the numeric type does not have infinity value, then the maximum
+ /// value is used as extremal infinity value.
+ template <
+ typename V,
+ bool has_inf = std::numeric_limits<V>::has_infinity>
+ struct BellmanFordDefaultOperationTraits {
+ /// \e
+ typedef V Value;
+ /// \brief Gives back the zero value of the type.
+ static Value zero() {
+ return static_cast<Value>(0);
+ }
+ /// \brief Gives back the positive infinity value of the type.
+ static Value infinity() {
+ return std::numeric_limits<Value>::infinity();
+ }
+ /// \brief Gives back the sum of the given two elements.
+ static Value plus(const Value& left, const Value& right) {
+ return left + right;
+ }
+ /// \brief Gives back \c true only if the first value is less than
+ /// the second.
+ static bool less(const Value& left, const Value& right) {
+ return left < right;
+ }
+ };
+
+ template <typename V>
+ struct BellmanFordDefaultOperationTraits<V, false> {
+ typedef V Value;
+ static Value zero() {
+ return static_cast<Value>(0);
+ }
+ static Value infinity() {
+ return std::numeric_limits<Value>::max();
+ }
+ static Value plus(const Value& left, const Value& right) {
+ if (left == infinity() || right == infinity()) return infinity();
+ return left + right;
+ }
+ static bool less(const Value& left, const Value& right) {
+ return left < right;
+ }
+ };
+
+ /// \brief Default traits class of BellmanFord class.
+ ///
+ /// Default traits class of BellmanFord class.
+ /// \param GR The type of the digraph.
+ /// \param LEN The type of the length map.
+ template<typename GR, typename LEN>
+ struct BellmanFordDefaultTraits {
+ /// The type of the digraph the algorithm runs on.
+ typedef GR Digraph;
+
+ /// \brief The type of the map that stores the arc lengths.
+ ///
+ /// The type of the map that stores the arc lengths.
+ /// It must conform to the \ref concepts::ReadMap "ReadMap" concept.
+ typedef LEN LengthMap;
+
+ /// The type of the arc lengths.
+ typedef typename LEN::Value Value;
+
+ /// \brief Operation traits for Bellman-Ford algorithm.
+ ///
+ /// It defines the used operations and the infinity value for the
+ /// given \c Value type.
+ /// \see BellmanFordDefaultOperationTraits
+ typedef BellmanFordDefaultOperationTraits<Value> OperationTraits;
+
+ /// \brief The type of the map that stores the last arcs of the
+ /// shortest paths.
+ ///
+ /// The type of the map that stores the last
+ /// arcs of the shortest paths.
+ /// It must conform to the \ref concepts::WriteMap "WriteMap" concept.
+ typedef typename GR::template NodeMap<typename GR::Arc> PredMap;
+
+ /// \brief Instantiates a \c PredMap.
+ ///
+ /// This function instantiates a \ref PredMap.
+ /// \param g is the digraph to which we would like to define the
+ /// \ref PredMap.
+ static PredMap *createPredMap(const GR& g) {
+ return new PredMap(g);
+ }
+
+ /// \brief 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 conform to the \ref concepts::WriteMap "WriteMap" concept.
+ typedef typename GR::template NodeMap<typename LEN::Value> DistMap;
+
+ /// \brief Instantiates a \c 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) {
+ return new DistMap(g);
+ }
+
+ };
+
+ /// \brief %BellmanFord algorithm class.
+ ///
+ /// \ingroup shortest_path
+ /// This class provides an efficient implementation of the Bellman-Ford
+ /// algorithm. The maximum time complexity of the algorithm is
+ /// <tt>O(ne)</tt>.
+ ///
+ /// The Bellman-Ford algorithm solves the single-source shortest path
+ /// problem when the arcs can have negative lengths, but the digraph
+ /// should not contain directed cycles with negative total length.
+ /// If all arc costs are non-negative, consider to use the Dijkstra
+ /// algorithm instead, since it is more efficient.
+ ///
+ /// 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 values is determined by the
+ /// \ref concepts::ReadMap::Value "Value" type of the length map.
+ ///
+ /// There is also a \ref bellmanFord() "function-type interface" for the
+ /// Bellman-Ford 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 type is \ref ListDigraph.
+ /// \tparam LEN A \ref concepts::ReadMap "readable" arc map that specifies
+ /// the lengths of the arcs. The default map type is
+ /// \ref concepts::Digraph::ArcMap "GR::ArcMap<int>".
+#ifdef DOXYGEN
+ template <typename GR, typename LEN, typename TR>
+#else
+ template <typename GR=ListDigraph,
+ typename LEN=typename GR::template ArcMap<int>,
+ typename TR=BellmanFordDefaultTraits<GR,LEN> >
+#endif
+ class BellmanFord {
+ public:
+
+ ///The type of the underlying digraph.
+ typedef typename TR::Digraph Digraph;
+
+ /// \brief The type of the arc lengths.
+ typedef typename TR::LengthMap::Value Value;
+ /// \brief 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.
+ typedef typename TR::PredMap PredMap;
+ /// \brief The type of the map that stores the distances of the nodes.
+ typedef typename TR::DistMap DistMap;
+ /// The type of the paths.
+ typedef PredMapPath<Digraph, PredMap> Path;
+ ///\brief The \ref BellmanFordDefaultOperationTraits
+ /// "operation traits class" of the algorithm.
+ typedef typename TR::OperationTraits OperationTraits;
+
+ ///The \ref BellmanFordDefaultTraits "traits class" of the algorithm.
+ typedef TR Traits;
+
+ private:
+
+ 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 *_gr;
+ // Pointer to the length map
+ const LengthMap *_length;
+ // Pointer to the map of predecessors arcs.
+ PredMap *_pred;
+ // Indicates if _pred is locally allocated (true) or not.
+ bool _local_pred;
+ // Pointer to the map of distances.
+ DistMap *_dist;
+ // Indicates if _dist is locally allocated (true) or not.
+ bool _local_dist;
+
+ typedef typename Digraph::template NodeMap<bool> MaskMap;
+ MaskMap *_mask;
+
+ std::vector<Node> _process;
+
+ // Creates the maps if necessary.
+ void create_maps() {
+ if(!_pred) {
+ _local_pred = true;
+ _pred = Traits::createPredMap(*_gr);
+ }
+ if(!_dist) {
+ _local_dist = true;
+ _dist = Traits::createDistMap(*_gr);
+ }
+ _mask = new MaskMap(*_gr, false);
+ }
+
+ public :
+
+ typedef BellmanFord Create;
+
+ /// \name Named Template Parameters
+
+ ///@{
+
+ template <class T>
+ struct SetPredMapTraits : public Traits {
+ typedef T PredMap;
+ static PredMap *createPredMap(const Digraph&) {
+ LEMON_ASSERT(false, "PredMap is not initialized");
+ return 0; // ignore warnings
+ }
+ };
+
+ /// \brief \ref named-templ-param "Named parameter" for setting
+ /// \c PredMap type.
+ ///
+ /// \ref named-templ-param "Named parameter" for setting
+ /// \c PredMap type.
+ /// It must conform to the \ref concepts::WriteMap "WriteMap" concept.
+ template <class T>
+ struct SetPredMap
+ : public BellmanFord< Digraph, LengthMap, SetPredMapTraits<T> > {
+ typedef BellmanFord< Digraph, LengthMap, SetPredMapTraits<T> > Create;
+ };
+
+ template <class T>
+ struct SetDistMapTraits : public Traits {
+ typedef T DistMap;
+ static DistMap *createDistMap(const Digraph&) {
+ LEMON_ASSERT(false, "DistMap is not initialized");
+ return 0; // ignore warnings
+ }
+ };
+
+ /// \brief \ref named-templ-param "Named parameter" for setting
+ /// \c DistMap type.
+ ///
+ /// \ref named-templ-param "Named parameter" for setting
+ /// \c DistMap type.
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