| //======================================================================= |
| // Copyright 1997, 1998, 1999, 2000 University of Notre Dame. |
| // Copyright 2003 Bruce Barr |
| // 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) |
| //======================================================================= |
| |
| // Nonrecursive implementation of depth_first_visit_impl submitted by |
| // Bruce Barr, schmoost <at> yahoo.com, May/June 2003. |
| #ifndef BOOST_GRAPH_RECURSIVE_DFS_HPP |
| #define BOOST_GRAPH_RECURSIVE_DFS_HPP |
| |
| #include <boost/config.hpp> |
| #include <boost/graph/graph_traits.hpp> |
| #include <boost/graph/graph_concepts.hpp> |
| #include <boost/graph/properties.hpp> |
| #include <boost/graph/visitors.hpp> |
| #include <boost/graph/named_function_params.hpp> |
| #include <boost/ref.hpp> |
| #include <boost/implicit_cast.hpp> |
| |
| #include <vector> |
| #include <utility> |
| |
| namespace boost { |
| |
| template <class Visitor, class Graph> |
| class DFSVisitorConcept { |
| public: |
| void constraints() { |
| function_requires< CopyConstructibleConcept<Visitor> >(); |
| vis.initialize_vertex(u, g); |
| vis.start_vertex(u, g); |
| vis.discover_vertex(u, g); |
| vis.examine_edge(e, g); |
| vis.tree_edge(e, g); |
| vis.back_edge(e, g); |
| vis.forward_or_cross_edge(e, g); |
| vis.finish_vertex(u, g); |
| } |
| private: |
| Visitor vis; |
| Graph g; |
| typename graph_traits<Graph>::vertex_descriptor u; |
| typename graph_traits<Graph>::edge_descriptor e; |
| }; |
| |
| namespace detail { |
| |
| struct nontruth2 { |
| template<class T, class T2> |
| bool operator()(const T&, const T2&) const { return false; } |
| }; |
| |
| |
| // Define BOOST_RECURSIVE_DFS to use older, recursive version. |
| // It is retained for a while in order to perform performance |
| // comparison. |
| #ifndef BOOST_RECURSIVE_DFS |
| |
| // If the vertex u and the iterators ei and ei_end are thought of as the |
| // context of the algorithm, each push and pop from the stack could |
| // be thought of as a context shift. |
| // Each pass through "while (ei != ei_end)" may refer to the out-edges of |
| // an entirely different vertex, because the context of the algorithm |
| // shifts every time a white adjacent vertex is discovered. |
| // The corresponding context shift back from the adjacent vertex occurs |
| // after all of its out-edges have been examined. |
| // |
| // See http://lists.boost.org/MailArchives/boost/msg48752.php for FAQ. |
| |
| template <class IncidenceGraph, class DFSVisitor, class ColorMap, |
| class TerminatorFunc> |
| void depth_first_visit_impl |
| (const IncidenceGraph& g, |
| typename graph_traits<IncidenceGraph>::vertex_descriptor u, |
| DFSVisitor& vis, |
| ColorMap color, TerminatorFunc func = TerminatorFunc()) |
| { |
| function_requires<IncidenceGraphConcept<IncidenceGraph> >(); |
| function_requires<DFSVisitorConcept<DFSVisitor, IncidenceGraph> >(); |
| typedef typename graph_traits<IncidenceGraph>::vertex_descriptor Vertex; |
| function_requires< ReadWritePropertyMapConcept<ColorMap, Vertex> >(); |
| typedef typename property_traits<ColorMap>::value_type ColorValue; |
| function_requires< ColorValueConcept<ColorValue> >(); |
| typedef color_traits<ColorValue> Color; |
| typedef typename graph_traits<IncidenceGraph>::out_edge_iterator Iter; |
| typedef std::pair<Vertex, std::pair<Iter, Iter> > VertexInfo; |
| |
| Iter ei, ei_end; |
| std::vector<VertexInfo> stack; |
| |
| // Possible optimization for vector |
| //stack.reserve(num_vertices(g)); |
| |
| typedef typename unwrap_reference<TerminatorFunc>::type TF; |
| |
| put(color, u, Color::gray()); |
| vis.discover_vertex(u, g); |
| boost::tie(ei, ei_end) = out_edges(u, g); |
| // Variable is needed to workaround a borland bug. |
| TF& fn = static_cast<TF&>(func); |
| if (fn(u, g)) { |
| // If this vertex terminates the search, we push empty range |
| stack.push_back(std::make_pair(u, std::make_pair(ei_end, ei_end))); |
| } else { |
| stack.push_back(std::make_pair(u, std::make_pair(ei, ei_end))); |
| } |
| while (!stack.empty()) { |
| VertexInfo& back = stack.back(); |
| u = back.first; |
| boost::tie(ei, ei_end) = back.second; |
| stack.pop_back(); |
| while (ei != ei_end) { |
| Vertex v = target(*ei, g); |
| vis.examine_edge(*ei, g); |
| ColorValue v_color = get(color, v); |
| if (v_color == Color::white()) { |
| vis.tree_edge(*ei, g); |
| stack.push_back(std::make_pair(u, std::make_pair(++ei, ei_end))); |
| u = v; |
| put(color, u, Color::gray()); |
| vis.discover_vertex(u, g); |
| boost::tie(ei, ei_end) = out_edges(u, g); |
| if (fn(u, g)) { |
| ei = ei_end; |
| } |
| } else if (v_color == Color::gray()) { |
| vis.back_edge(*ei, g); |
| ++ei; |
| } else { |
| vis.forward_or_cross_edge(*ei, g); |
| ++ei; |
| } |
| } |
| put(color, u, Color::black()); |
| vis.finish_vertex(u, g); |
| } |
| } |
| |
| #else // BOOST_RECURSIVE_DFS is defined |
| |
| template <class IncidenceGraph, class DFSVisitor, class ColorMap, |
| class TerminatorFunc> |
| void depth_first_visit_impl |
| (const IncidenceGraph& g, |
| typename graph_traits<IncidenceGraph>::vertex_descriptor u, |
| DFSVisitor& vis, // pass-by-reference here, important! |
| ColorMap color, TerminatorFunc func) |
| { |
| function_requires<IncidenceGraphConcept<IncidenceGraph> >(); |
| function_requires<DFSVisitorConcept<DFSVisitor, IncidenceGraph> >(); |
| typedef typename graph_traits<IncidenceGraph>::vertex_descriptor Vertex; |
| function_requires< ReadWritePropertyMapConcept<ColorMap, Vertex> >(); |
| typedef typename property_traits<ColorMap>::value_type ColorValue; |
| function_requires< ColorValueConcept<ColorValue> >(); |
| typedef color_traits<ColorValue> Color; |
| typename graph_traits<IncidenceGraph>::out_edge_iterator ei, ei_end; |
| |
| put(color, u, Color::gray()); vis.discover_vertex(u, g); |
| |
| typedef typename unwrap_reference<TerminatorFunc>::type TF; |
| // Variable is needed to workaround a borland bug. |
| TF& fn = static_cast<TF&>(func); |
| if (!fn(u, g)) |
| for (boost::tie(ei, ei_end) = out_edges(u, g); ei != ei_end; ++ei) { |
| Vertex v = target(*ei, g); vis.examine_edge(*ei, g); |
| ColorValue v_color = get(color, v); |
| if (v_color == Color::white()) { vis.tree_edge(*ei, g); |
| depth_first_visit_impl(g, v, vis, color, func); |
| } else if (v_color == Color::gray()) vis.back_edge(*ei, g); |
| else vis.forward_or_cross_edge(*ei, g); |
| } |
| put(color, u, Color::black()); vis.finish_vertex(u, g); |
| } |
| |
| #endif |
| |
| } // namespace detail |
| |
| template <class VertexListGraph, class DFSVisitor, class ColorMap> |
| void |
| depth_first_search(const VertexListGraph& g, DFSVisitor vis, ColorMap color, |
| typename graph_traits<VertexListGraph>::vertex_descriptor start_vertex) |
| { |
| typedef typename graph_traits<VertexListGraph>::vertex_descriptor Vertex; |
| function_requires<DFSVisitorConcept<DFSVisitor, VertexListGraph> >(); |
| 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) { |
| Vertex u = implicit_cast<Vertex>(*ui); |
| put(color, u, Color::white()); vis.initialize_vertex(u, g); |
| } |
| |
| if (start_vertex != implicit_cast<Vertex>(*vertices(g).first)){ vis.start_vertex(start_vertex, g); |
| detail::depth_first_visit_impl(g, start_vertex, vis, color, |
| detail::nontruth2()); |
| } |
| |
| for (boost::tie(ui, ui_end) = vertices(g); ui != ui_end; ++ui) { |
| Vertex u = implicit_cast<Vertex>(*ui); |
| ColorValue u_color = get(color, u); |
| if (u_color == Color::white()) { vis.start_vertex(u, g); |
| detail::depth_first_visit_impl(g, u, vis, color, detail::nontruth2()); |
| } |
| } |
| } |
| |
| template <class VertexListGraph, class DFSVisitor, class ColorMap> |
| void |
| depth_first_search(const VertexListGraph& g, DFSVisitor vis, ColorMap color) |
| { |
| typedef typename boost::graph_traits<VertexListGraph>::vertex_iterator vi; |
| std::pair<vi, vi> verts = vertices(g); |
| if (verts.first == verts.second) |
| return; |
| |
| depth_first_search(g, vis, color, *verts.first); |
| } |
| |
| template <class Visitors = null_visitor> |
| class dfs_visitor { |
| public: |
| dfs_visitor() { } |
| dfs_visitor(Visitors vis) : m_vis(vis) { } |
| |
| template <class Vertex, class Graph> |
| void initialize_vertex(Vertex u, const Graph& g) { |
| invoke_visitors(m_vis, u, g, ::boost::on_initialize_vertex()); |
| } |
| template <class Vertex, class Graph> |
| void start_vertex(Vertex u, const Graph& g) { |
| invoke_visitors(m_vis, u, g, ::boost::on_start_vertex()); |
| } |
| template <class Vertex, class Graph> |
| void discover_vertex(Vertex u, const Graph& g) { |
| invoke_visitors(m_vis, u, g, ::boost::on_discover_vertex()); |
| } |
| template <class Edge, class Graph> |
| void examine_edge(Edge u, const Graph& g) { |
| invoke_visitors(m_vis, u, g, ::boost::on_examine_edge()); |
| } |
| template <class Edge, class Graph> |
| void tree_edge(Edge u, const Graph& g) { |
| invoke_visitors(m_vis, u, g, ::boost::on_tree_edge()); |
| } |
| template <class Edge, class Graph> |
| void back_edge(Edge u, const Graph& g) { |
| invoke_visitors(m_vis, u, g, ::boost::on_back_edge()); |
| } |
| template <class Edge, class Graph> |
| void forward_or_cross_edge(Edge u, const Graph& g) { |
| invoke_visitors(m_vis, u, g, ::boost::on_forward_or_cross_edge()); |
| } |
| template <class Vertex, class Graph> |
| void finish_vertex(Vertex u, const Graph& g) { |
| invoke_visitors(m_vis, u, g, ::boost::on_finish_vertex()); |
| } |
| |
| BOOST_GRAPH_EVENT_STUB(on_initialize_vertex,dfs) |
| BOOST_GRAPH_EVENT_STUB(on_start_vertex,dfs) |
| BOOST_GRAPH_EVENT_STUB(on_discover_vertex,dfs) |
| BOOST_GRAPH_EVENT_STUB(on_examine_edge,dfs) |
| BOOST_GRAPH_EVENT_STUB(on_tree_edge,dfs) |
| BOOST_GRAPH_EVENT_STUB(on_back_edge,dfs) |
| BOOST_GRAPH_EVENT_STUB(on_forward_or_cross_edge,dfs) |
| BOOST_GRAPH_EVENT_STUB(on_finish_vertex,dfs) |
| |
| protected: |
| Visitors m_vis; |
| }; |
| template <class Visitors> |
| dfs_visitor<Visitors> |
| make_dfs_visitor(Visitors vis) { |
| return dfs_visitor<Visitors>(vis); |
| } |
| typedef dfs_visitor<> default_dfs_visitor; |
| |
| // Named Parameter Variant |
| template <class VertexListGraph, class P, class T, class R> |
| void |
| depth_first_search(const VertexListGraph& g, |
| const bgl_named_params<P, T, R>& params) |
| { |
| typedef typename boost::graph_traits<VertexListGraph>::vertex_iterator vi; |
| std::pair<vi, vi> verts = vertices(g); |
| if (verts.first == verts.second) |
| return; |
| using namespace boost::graph::keywords; |
| typedef bgl_named_params<P, T, R> params_type; |
| BOOST_GRAPH_DECLARE_CONVERTED_PARAMETERS(params_type, params) |
| depth_first_search |
| (g, |
| arg_pack[_visitor | make_dfs_visitor(null_visitor())], |
| boost::detail::make_color_map_from_arg_pack(g, arg_pack), |
| arg_pack[_root_vertex | *vertices(g).first] |
| ); |
| } |
| |
| template <class IncidenceGraph, class DFSVisitor, class ColorMap> |
| void depth_first_visit |
| (const IncidenceGraph& g, |
| typename graph_traits<IncidenceGraph>::vertex_descriptor u, |
| DFSVisitor vis, ColorMap color) |
| { |
| vis.start_vertex(u, g); |
| detail::depth_first_visit_impl(g, u, vis, color, detail::nontruth2()); |
| } |
| |
| template <class IncidenceGraph, class DFSVisitor, class ColorMap, |
| class TerminatorFunc> |
| void depth_first_visit |
| (const IncidenceGraph& g, |
| typename graph_traits<IncidenceGraph>::vertex_descriptor u, |
| DFSVisitor vis, ColorMap color, TerminatorFunc func = TerminatorFunc()) |
| { |
| vis.start_vertex(u, g); |
| detail::depth_first_visit_impl(g, u, vis, color, func); |
| } |
| } // namespace boost |
| |
| #ifdef BOOST_GRAPH_USE_MPI |
| # include <boost/graph/distributed/depth_first_search.hpp> |
| #endif |
| |
| #endif |