boost/graph/dijkstra_shortest_paths.hpp
//======================================================================= // Copyright 1997, 1998, 1999, 2000 University of Notre Dame. // Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek // // Distributed under the Boost Software License, Version 1.0. (See // accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) //======================================================================= // // // Revision History: // 04 April 2001: Added named parameter variant. (Jeremy Siek) // 01 April 2001: Modified to use new <boost/limits.hpp> header. (JMaddock) // #ifndef BOOST_GRAPH_DIJKSTRA_HPP #define BOOST_GRAPH_DIJKSTRA_HPP #include <functional> #include <boost/limits.hpp> #include <boost/graph/named_function_params.hpp> #include <boost/graph/breadth_first_search.hpp> #include <boost/graph/relax.hpp> #include <boost/pending/indirect_cmp.hpp> #include <boost/graph/exception.hpp> #include <boost/pending/relaxed_heap.hpp> #include <boost/graph/overloading.hpp> #include <boost/smart_ptr.hpp> #include <boost/graph/detail/d_ary_heap.hpp> #include <boost/graph/two_bit_color_map.hpp> #include <boost/property_map/property_map.hpp> #include <boost/property_map/vector_property_map.hpp> #include <boost/type_traits.hpp> #include <boost/concept/assert.hpp> #ifdef BOOST_GRAPH_DIJKSTRA_TESTING # include <boost/pending/mutable_queue.hpp> #endif // BOOST_GRAPH_DIJKSTRA_TESTING namespace boost { /** * @brief Updates a particular value in a queue used by Dijkstra's * algorithm. * * This routine is called by Dijkstra's algorithm after it has * decreased the distance from the source vertex to the given @p * vertex. By default, this routine will just call @c * Q.update(vertex). However, other queues may provide more * specialized versions of this routine. * * @param Q the queue that will be updated. * @param vertex the vertex whose distance has been updated * @param old_distance the previous distance to @p vertex */ template<typename Buffer, typename Vertex, typename DistanceType> inline void dijkstra_queue_update(Buffer& Q, Vertex vertex, DistanceType old_distance) { (void)old_distance; Q.update(vertex); } #ifdef BOOST_GRAPH_DIJKSTRA_TESTING // This is a misnomer now: it now just refers to the "default heap", which is // currently d-ary (d=4) but can be changed by a #define. static bool dijkstra_relaxed_heap = true; #endif template <class Visitor, class Graph> struct DijkstraVisitorConcept { void constraints() { BOOST_CONCEPT_ASSERT(( CopyConstructibleConcept<Visitor> )); vis.initialize_vertex(u, g); vis.discover_vertex(u, g); vis.examine_vertex(u, g); vis.examine_edge(e, g); vis.edge_relaxed(e, g); vis.edge_not_relaxed(e, g); vis.finish_vertex(u, g); } Visitor vis; Graph g; typename graph_traits<Graph>::vertex_descriptor u; typename graph_traits<Graph>::edge_descriptor e; }; template <class Visitors = null_visitor> class dijkstra_visitor : public bfs_visitor<Visitors> { public: dijkstra_visitor() { } dijkstra_visitor(Visitors vis) : bfs_visitor<Visitors>(vis) { } template <class Edge, class Graph> void edge_relaxed(Edge e, Graph& g) { invoke_visitors(this->m_vis, e, g, on_edge_relaxed()); } template <class Edge, class Graph> void edge_not_relaxed(Edge e, Graph& g) { invoke_visitors(this->m_vis, e, g, on_edge_not_relaxed()); } private: template <class Edge, class Graph> void tree_edge(Edge u, Graph& g) { } }; template <class Visitors> dijkstra_visitor<Visitors> make_dijkstra_visitor(Visitors vis) { return dijkstra_visitor<Visitors>(vis); } typedef dijkstra_visitor<> default_dijkstra_visitor; namespace detail { template <class UniformCostVisitor, class UpdatableQueue, class WeightMap, class PredecessorMap, class DistanceMap, class BinaryFunction, class BinaryPredicate> struct dijkstra_bfs_visitor { typedef typename property_traits<DistanceMap>::value_type D; dijkstra_bfs_visitor(UniformCostVisitor vis, UpdatableQueue& Q, WeightMap w, PredecessorMap p, DistanceMap d, BinaryFunction combine, BinaryPredicate compare, D zero) : m_vis(vis), m_Q(Q), m_weight(w), m_predecessor(p), m_distance(d), m_combine(combine), m_compare(compare), m_zero(zero) { } template <class Edge, class Graph> void tree_edge(Edge e, Graph& g) { bool decreased = relax(e, g, m_weight, m_predecessor, m_distance, m_combine, m_compare); if (decreased) m_vis.edge_relaxed(e, g); else m_vis.edge_not_relaxed(e, g); } template <class Edge, class Graph> void gray_target(Edge e, Graph& g) { D old_distance = get(m_distance, target(e, g)); bool decreased = relax(e, g, m_weight, m_predecessor, m_distance, m_combine, m_compare); if (decreased) { dijkstra_queue_update(m_Q, target(e, g), old_distance); m_vis.edge_relaxed(e, g); } else m_vis.edge_not_relaxed(e, g); } template <class Vertex, class Graph> void initialize_vertex(Vertex u, Graph& g) { m_vis.initialize_vertex(u, g); } template <class Edge, class Graph> void non_tree_edge(Edge, Graph&) { } template <class Vertex, class Graph> void discover_vertex(Vertex u, Graph& g) { m_vis.discover_vertex(u, g); } template <class Vertex, class Graph> void examine_vertex(Vertex u, Graph& g) { m_vis.examine_vertex(u, g); } template <class Edge, class Graph> void examine_edge(Edge e, Graph& g) { if (m_compare(get(m_weight, e), m_zero)) boost::throw_exception(negative_edge()); m_vis.examine_edge(e, g); } template <class Edge, class Graph> void black_target(Edge, Graph&) { } template <class Vertex, class Graph> void finish_vertex(Vertex u, Graph& g) { m_vis.finish_vertex(u, g); } UniformCostVisitor m_vis; UpdatableQueue& m_Q; WeightMap m_weight; PredecessorMap m_predecessor; DistanceMap m_distance; BinaryFunction m_combine; BinaryPredicate m_compare; D m_zero; }; } // namespace detail namespace detail { template <class Graph, class IndexMap, class Value, bool KnownNumVertices> struct vertex_property_map_generator_helper {}; template <class Graph, class IndexMap, class Value> struct vertex_property_map_generator_helper<Graph, IndexMap, Value, true> { typedef boost::iterator_property_map<Value*, IndexMap> type; static type build(const Graph& g, const IndexMap& index, boost::scoped_array<Value>& array_holder) { array_holder.reset(new Value[num_vertices(g)]); std::fill(array_holder.get(), array_holder.get() + num_vertices(g), Value()); return make_iterator_property_map(array_holder.get(), index); } }; template <class Graph, class IndexMap, class Value> struct vertex_property_map_generator_helper<Graph, IndexMap, Value, false> { typedef boost::vector_property_map<Value, IndexMap> type; static type build(const Graph& g, const IndexMap& index, boost::scoped_array<Value>& array_holder) { return boost::make_vector_property_map<Value>(index); } }; template <class Graph, class IndexMap, class Value> struct vertex_property_map_generator { typedef boost::is_base_and_derived< boost::vertex_list_graph_tag, typename boost::graph_traits<Graph>::traversal_category> known_num_vertices; typedef vertex_property_map_generator_helper<Graph, IndexMap, Value, known_num_vertices::value> helper; typedef typename helper::type type; static type build(const Graph& g, const IndexMap& index, boost::scoped_array<Value>& array_holder) { return helper::build(g, index, array_holder); } }; } namespace detail { template <class Graph, class IndexMap, bool KnownNumVertices> struct default_color_map_generator_helper {}; template <class Graph, class IndexMap> struct default_color_map_generator_helper<Graph, IndexMap, true> { typedef boost::two_bit_color_map<IndexMap> type; static type build(const Graph& g, const IndexMap& index) { size_t nv = num_vertices(g); return boost::two_bit_color_map<IndexMap>(nv, index); } }; template <class Graph, class IndexMap> struct default_color_map_generator_helper<Graph, IndexMap, false> { typedef boost::vector_property_map<boost::two_bit_color_type, IndexMap> type; static type build(const Graph& g, const IndexMap& index) { return boost::make_vector_property_map<boost::two_bit_color_type>(index); } }; template <class Graph, class IndexMap> struct default_color_map_generator { typedef boost::is_base_and_derived< boost::vertex_list_graph_tag, typename boost::graph_traits<Graph>::traversal_category> known_num_vertices; typedef default_color_map_generator_helper<Graph, IndexMap, known_num_vertices::value> helper; typedef typename helper::type type; static type build(const Graph& g, const IndexMap& index) { return helper::build(g, index); } }; } // Call breadth first search with default color map. template <class Graph, class DijkstraVisitor, class PredecessorMap, class DistanceMap, class WeightMap, class IndexMap, class Compare, class Combine, class DistZero> inline void dijkstra_shortest_paths_no_init (const Graph& g, typename graph_traits<Graph>::vertex_descriptor s, PredecessorMap predecessor, DistanceMap distance, WeightMap weight, IndexMap index_map, Compare compare, Combine combine, DistZero zero, DijkstraVisitor vis) { typedef detail::default_color_map_generator<Graph, IndexMap> ColorMapHelper; typedef typename ColorMapHelper::type ColorMap; ColorMap color = ColorMapHelper::build(g, index_map); dijkstra_shortest_paths_no_init( g, s, predecessor, distance, weight, index_map, compare, combine, zero, vis, color); } // Call breadth first search template <class Graph, class DijkstraVisitor, class PredecessorMap, class DistanceMap, class WeightMap, class IndexMap, class Compare, class Combine, class DistZero, class ColorMap> inline void dijkstra_shortest_paths_no_init (const Graph& g, typename graph_traits<Graph>::vertex_descriptor s, PredecessorMap predecessor, DistanceMap distance, WeightMap weight, IndexMap index_map, Compare compare, Combine combine, DistZero zero, DijkstraVisitor vis, ColorMap color) { typedef indirect_cmp<DistanceMap, Compare> IndirectCmp; IndirectCmp icmp(distance, compare); typedef typename graph_traits<Graph>::vertex_descriptor Vertex; #ifdef BOOST_GRAPH_DIJKSTRA_TESTING if (!dijkstra_relaxed_heap) { typedef mutable_queue<Vertex, std::vector<Vertex>, IndirectCmp, IndexMap> MutableQueue; MutableQueue Q(num_vertices(g), icmp, index_map); detail::dijkstra_bfs_visitor<DijkstraVisitor, MutableQueue, WeightMap, PredecessorMap, DistanceMap, Combine, Compare> bfs_vis(vis, Q, weight, predecessor, distance, combine, compare, zero); breadth_first_visit(g, s, Q, bfs_vis, color); return; } #endif // BOOST_GRAPH_DIJKSTRA_TESTING #ifdef BOOST_GRAPH_DIJKSTRA_USE_RELAXED_HEAP typedef relaxed_heap<Vertex, IndirectCmp, IndexMap> MutableQueue; MutableQueue Q(num_vertices(g), icmp, index_map); #else // Now the default: use a d-ary heap boost::scoped_array<std::size_t> index_in_heap_map_holder; typedef detail::vertex_property_map_generator<Graph, IndexMap, std::size_t> IndexInHeapMapHelper; typedef typename IndexInHeapMapHelper::type IndexInHeapMap; IndexInHeapMap index_in_heap = IndexInHeapMapHelper::build(g, index_map, index_in_heap_map_holder); typedef d_ary_heap_indirect<Vertex, 4, IndexInHeapMap, DistanceMap, Compare> MutableQueue; MutableQueue Q(distance, index_in_heap, compare); #endif // Relaxed heap detail::dijkstra_bfs_visitor<DijkstraVisitor, MutableQueue, WeightMap, PredecessorMap, DistanceMap, Combine, Compare> bfs_vis(vis, Q, weight, predecessor, distance, combine, compare, zero); breadth_first_visit(g, s, Q, bfs_vis, color); } // Initialize distances and call breadth first search with default color map template <class VertexListGraph, class DijkstraVisitor, class PredecessorMap, class DistanceMap, class WeightMap, class IndexMap, class Compare, class Combine, class DistInf, class DistZero, typename T, typename Tag, typename Base> inline void dijkstra_shortest_paths (const VertexListGraph& g, typename graph_traits<VertexListGraph>::vertex_descriptor s, PredecessorMap predecessor, DistanceMap distance, WeightMap weight, IndexMap index_map, Compare compare, Combine combine, DistInf inf, DistZero zero, DijkstraVisitor vis, const bgl_named_params<T, Tag, Base>& BOOST_GRAPH_ENABLE_IF_MODELS_PARM(VertexListGraph,vertex_list_graph_tag)) { boost::two_bit_color_map<IndexMap> color(num_vertices(g), index_map); dijkstra_shortest_paths(g, s, predecessor, distance, weight, index_map, compare, combine, inf, zero, vis, color); } // Initialize distances and call breadth first search template <class VertexListGraph, class DijkstraVisitor, class PredecessorMap, class DistanceMap, class WeightMap, class IndexMap, class Compare, class Combine, class DistInf, class DistZero, class ColorMap> inline void dijkstra_shortest_paths (const VertexListGraph& g, typename graph_traits<VertexListGraph>::vertex_descriptor s, PredecessorMap predecessor, DistanceMap distance, WeightMap weight, IndexMap index_map, Compare compare, Combine combine, DistInf inf, DistZero zero, DijkstraVisitor vis, ColorMap color) { typedef typename property_traits<ColorMap>::value_type ColorValue; typedef color_traits<ColorValue> Color; typename graph_traits<VertexListGraph>::vertex_iterator ui, ui_end; for (boost::tie(ui, ui_end) = vertices(g); ui != ui_end; ++ui) { vis.initialize_vertex(*ui, g); put(distance, *ui, inf); put(predecessor, *ui, *ui); put(color, *ui, Color::white()); } put(distance, s, zero); dijkstra_shortest_paths_no_init(g, s, predecessor, distance, weight, index_map, compare, combine, zero, vis, color); } // Initialize distances and call breadth first search template <class VertexListGraph, class DijkstraVisitor, class PredecessorMap, class DistanceMap, class WeightMap, class IndexMap, class Compare, class Combine, class DistInf, class DistZero> inline void dijkstra_shortest_paths (const VertexListGraph& g, typename graph_traits<VertexListGraph>::vertex_descriptor s, PredecessorMap predecessor, DistanceMap distance, WeightMap weight, IndexMap index_map, Compare compare, Combine combine, DistInf inf, DistZero zero, DijkstraVisitor vis) { dijkstra_shortest_paths(g, s, predecessor, distance, weight, index_map, compare, combine, inf, zero, vis, no_named_parameters()); } namespace detail { // Handle defaults for PredecessorMap and // Distance Compare, Combine, Inf and Zero template <class VertexListGraph, class DistanceMap, class WeightMap, class IndexMap, class Params> inline void dijkstra_dispatch2 (const VertexListGraph& g, typename graph_traits<VertexListGraph>::vertex_descriptor s, DistanceMap distance, WeightMap weight, IndexMap index_map, const Params& params) { // Default for predecessor map dummy_property_map p_map; typedef typename property_traits<DistanceMap>::value_type D; D inf = choose_param(get_param(params, distance_inf_t()), (std::numeric_limits<D>::max)()); dijkstra_shortest_paths (g, s, choose_param(get_param(params, vertex_predecessor), p_map), distance, weight, index_map, choose_param(get_param(params, distance_compare_t()), std::less<D>()), choose_param(get_param(params, distance_combine_t()), closed_plus<D>(inf)), inf, choose_param(get_param(params, distance_zero_t()), D()), choose_param(get_param(params, graph_visitor), make_dijkstra_visitor(null_visitor())), params); } template <class VertexListGraph, class DistanceMap, class WeightMap, class IndexMap, class Params> inline void dijkstra_dispatch1 (const VertexListGraph& g, typename graph_traits<VertexListGraph>::vertex_descriptor s, DistanceMap distance, WeightMap weight, IndexMap index_map, const Params& params) { // Default for distance map typedef typename property_traits<WeightMap>::value_type D; typename std::vector<D>::size_type n = is_default_param(distance) ? num_vertices(g) : 1; std::vector<D> distance_map(n); detail::dijkstra_dispatch2 (g, s, choose_param(distance, make_iterator_property_map (distance_map.begin(), index_map, distance_map[0])), weight, index_map, params); } } // namespace detail // Named Parameter Variant template <class VertexListGraph, class Param, class Tag, class Rest> inline void dijkstra_shortest_paths (const VertexListGraph& g, typename graph_traits<VertexListGraph>::vertex_descriptor s, const bgl_named_params<Param,Tag,Rest>& params) { // Default for edge weight and vertex index map is to ask for them // from the graph. Default for the visitor is null_visitor. detail::dijkstra_dispatch1 (g, s, get_param(params, vertex_distance), choose_const_pmap(get_param(params, edge_weight), g, edge_weight), choose_const_pmap(get_param(params, vertex_index), g, vertex_index), params); } } // namespace boost #ifdef BOOST_GRAPH_USE_MPI # include <boost/graph/distributed/dijkstra_shortest_paths.hpp> #endif #endif // BOOST_GRAPH_DIJKSTRA_HPP