ossrv_pub/boost_apis/boost/graph/breadth_first_search.hpp
changeset 0 e4d67989cc36
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ossrv_pub/boost_apis/boost/graph/breadth_first_search.hpp	Tue Feb 02 02:01:42 2010 +0200
@@ -0,0 +1,293 @@
+//
+//=======================================================================
+// 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)
+//=======================================================================
+//
+#ifndef BOOST_GRAPH_BREADTH_FIRST_SEARCH_HPP
+#define BOOST_GRAPH_BREADTH_FIRST_SEARCH_HPP
+
+/*
+  Breadth First Search Algorithm (Cormen, Leiserson, and Rivest p. 470)
+*/
+#include <boost/config.hpp>
+#include <vector>
+#include <boost/pending/queue.hpp>
+#include <boost/graph/graph_traits.hpp>
+#include <boost/graph/graph_concepts.hpp>
+#include <boost/graph/visitors.hpp>
+#include <boost/graph/named_function_params.hpp>
+
+namespace boost {
+
+  template <class Visitor, class Graph>
+  struct BFSVisitorConcept {
+    void constraints() {
+      function_requires< CopyConstructibleConcept<Visitor> >();
+      vis.initialize_vertex(u, g);
+      vis.discover_vertex(u, g);
+      vis.examine_vertex(u, g);
+      vis.examine_edge(e, g);
+      vis.tree_edge(e, g);
+      vis.non_tree_edge(e, g);
+      vis.gray_target(e, g);
+      vis.black_target(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 IncidenceGraph, class Buffer, class BFSVisitor,
+            class ColorMap>
+  void breadth_first_visit
+    (const IncidenceGraph& g,
+     typename graph_traits<IncidenceGraph>::vertex_descriptor s,
+     Buffer& Q, BFSVisitor vis, ColorMap color)
+  {
+    function_requires< IncidenceGraphConcept<IncidenceGraph> >();
+    typedef graph_traits<IncidenceGraph> GTraits;
+    typedef typename GTraits::vertex_descriptor Vertex;
+    typedef typename GTraits::edge_descriptor Edge;
+    function_requires< BFSVisitorConcept<BFSVisitor, IncidenceGraph> >();
+    function_requires< ReadWritePropertyMapConcept<ColorMap, Vertex> >();
+    typedef typename property_traits<ColorMap>::value_type ColorValue;
+    typedef color_traits<ColorValue> Color;
+    typename GTraits::out_edge_iterator ei, ei_end;
+
+    put(color, s, Color::gray());             vis.discover_vertex(s, g);
+    Q.push(s);
+    while (! Q.empty()) {
+      Vertex u = Q.top(); Q.pop();            vis.examine_vertex(u, g);
+      for (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);
+          put(color, v, Color::gray());       vis.discover_vertex(v, g);
+          Q.push(v);
+        } else {                              vis.non_tree_edge(*ei, g);
+          if (v_color == Color::gray())       vis.gray_target(*ei, g);
+          else                                vis.black_target(*ei, g);
+        }
+      } // end for
+      put(color, u, Color::black());          vis.finish_vertex(u, g);
+    } // end while
+  } // breadth_first_visit
+
+
+  template <class VertexListGraph, class Buffer, class BFSVisitor,
+            class ColorMap>
+  void breadth_first_search
+    (const VertexListGraph& g,
+     typename graph_traits<VertexListGraph>::vertex_descriptor s,
+     Buffer& Q, BFSVisitor vis, ColorMap color)
+  {
+    // Initialization
+    typedef typename property_traits<ColorMap>::value_type ColorValue;
+    typedef color_traits<ColorValue> Color;
+    typename boost::graph_traits<VertexListGraph>::vertex_iterator i, i_end;
+    for (tie(i, i_end) = vertices(g); i != i_end; ++i) {
+      vis.initialize_vertex(*i, g);
+      put(color, *i, Color::white());
+    }
+    breadth_first_visit(g, s, Q, vis, color);
+  }
+
+
+  template <class Visitors = null_visitor>
+  class bfs_visitor {
+  public:
+    bfs_visitor() { }
+    bfs_visitor(Visitors vis) : m_vis(vis) { }
+
+    template <class Vertex, class Graph>
+    void initialize_vertex(Vertex u, Graph& g) {
+      invoke_visitors(m_vis, u, g, ::boost::on_initialize_vertex());
+    }
+    template <class Vertex, class Graph>
+    void discover_vertex(Vertex u, Graph& g) {
+      invoke_visitors(m_vis, u, g, ::boost::on_discover_vertex());
+    }
+    template <class Vertex, class Graph>
+    void examine_vertex(Vertex u, Graph& g) {
+      invoke_visitors(m_vis, u, g, ::boost::on_examine_vertex());
+    }
+    template <class Edge, class Graph>
+    void examine_edge(Edge e, Graph& g) {
+      invoke_visitors(m_vis, e, g, ::boost::on_examine_edge());
+    }
+    template <class Edge, class Graph>
+    void tree_edge(Edge e, Graph& g) {
+      invoke_visitors(m_vis, e, g, ::boost::on_tree_edge());
+    }
+    template <class Edge, class Graph>
+    void non_tree_edge(Edge e, Graph& g) {
+      invoke_visitors(m_vis, e, g, ::boost::on_non_tree_edge());
+    }
+    template <class Edge, class Graph>
+    void gray_target(Edge e, Graph& g) {
+      invoke_visitors(m_vis, e, g, ::boost::on_gray_target());
+    }
+    template <class Edge, class Graph>
+    void black_target(Edge e, Graph& g) {
+      invoke_visitors(m_vis, e, g, ::boost::on_black_target());
+    }
+    template <class Vertex, class Graph>
+    void finish_vertex(Vertex u, Graph& g) {
+      invoke_visitors(m_vis, u, g, ::boost::on_finish_vertex());
+    }
+
+    BOOST_GRAPH_EVENT_STUB(on_initialize_vertex,bfs)
+    BOOST_GRAPH_EVENT_STUB(on_discover_vertex,bfs)
+    BOOST_GRAPH_EVENT_STUB(on_examine_vertex,bfs)
+    BOOST_GRAPH_EVENT_STUB(on_examine_edge,bfs)
+    BOOST_GRAPH_EVENT_STUB(on_tree_edge,bfs)
+    BOOST_GRAPH_EVENT_STUB(on_non_tree_edge,bfs)
+    BOOST_GRAPH_EVENT_STUB(on_gray_target,bfs)
+    BOOST_GRAPH_EVENT_STUB(on_black_target,bfs)
+    BOOST_GRAPH_EVENT_STUB(on_finish_vertex,bfs)
+
+  protected:
+    Visitors m_vis;
+  };
+  template <class Visitors>
+  bfs_visitor<Visitors>
+  make_bfs_visitor(Visitors vis) {
+    return bfs_visitor<Visitors>(vis);
+  }
+  typedef bfs_visitor<> default_bfs_visitor;
+
+
+  namespace detail {
+
+    template <class VertexListGraph, class ColorMap, class BFSVisitor,
+      class P, class T, class R>
+    void bfs_helper
+      (VertexListGraph& g,
+       typename graph_traits<VertexListGraph>::vertex_descriptor s,
+       ColorMap color,
+       BFSVisitor vis,
+       const bgl_named_params<P, T, R>& params)
+    {
+      typedef graph_traits<VertexListGraph> Traits;
+      // Buffer default
+      typedef typename Traits::vertex_descriptor Vertex;
+      typedef boost::queue<Vertex> queue_t;
+      queue_t Q;
+      detail::wrap_ref<queue_t> Qref(Q);
+      breadth_first_search
+        (g, s,
+         choose_param(get_param(params, buffer_param_t()), Qref).ref,
+         vis, color);
+    }
+
+    //-------------------------------------------------------------------------
+    // Choose between default color and color parameters. Using
+    // function dispatching so that we don't require vertex index if
+    // the color default is not being used.
+
+    template <class ColorMap>
+    struct bfs_dispatch {
+      template <class VertexListGraph, class P, class T, class R>
+      static void apply
+      (VertexListGraph& g,
+       typename graph_traits<VertexListGraph>::vertex_descriptor s,
+       const bgl_named_params<P, T, R>& params,
+       ColorMap color)
+      {
+        bfs_helper
+          (g, s, color,
+           choose_param(get_param(params, graph_visitor),
+                        make_bfs_visitor(null_visitor())),
+           params);
+      }
+    };
+
+    template <>
+    struct bfs_dispatch<detail::error_property_not_found> {
+      template <class VertexListGraph, class P, class T, class R>
+      static void apply
+      (VertexListGraph& g,
+       typename graph_traits<VertexListGraph>::vertex_descriptor s,
+       const bgl_named_params<P, T, R>& params,
+       detail::error_property_not_found)
+      {
+        std::vector<default_color_type> color_vec(num_vertices(g));
+        default_color_type c = white_color;
+        null_visitor null_vis;
+
+        bfs_helper
+          (g, s,
+           make_iterator_property_map
+           (color_vec.begin(),
+            choose_const_pmap(get_param(params, vertex_index),
+                              g, vertex_index), c),
+           choose_param(get_param(params, graph_visitor),
+                        make_bfs_visitor(null_vis)),
+           params);
+      }
+    };
+
+  } // namespace detail
+
+
+  // Named Parameter Variant
+  template <class VertexListGraph, class P, class T, class R>
+  void breadth_first_search
+    (const VertexListGraph& g,
+     typename graph_traits<VertexListGraph>::vertex_descriptor s,
+     const bgl_named_params<P, T, R>& params)
+  {
+    // The graph is passed by *const* reference so that graph adaptors
+    // (temporaries) can be passed into this function. However, the
+    // graph is not really const since we may write to property maps
+    // of the graph.
+    VertexListGraph& ng = const_cast<VertexListGraph&>(g);
+    typedef typename property_value< bgl_named_params<P,T,R>,
+      vertex_color_t>::type C;
+    detail::bfs_dispatch<C>::apply(ng, s, params,
+                                   get_param(params, vertex_color));
+  }
+
+
+  // This version does not initialize colors, user has to.
+
+  template <class IncidenceGraph, class P, class T, class R>
+  void breadth_first_visit
+    (const IncidenceGraph& g,
+     typename graph_traits<IncidenceGraph>::vertex_descriptor s,
+     const bgl_named_params<P, T, R>& params)
+  {
+    // The graph is passed by *const* reference so that graph adaptors
+    // (temporaries) can be passed into this function. However, the
+    // graph is not really const since we may write to property maps
+    // of the graph.
+    IncidenceGraph& ng = const_cast<IncidenceGraph&>(g);
+
+    typedef graph_traits<IncidenceGraph> Traits;
+    // Buffer default
+    typedef typename Traits::vertex_descriptor vertex_descriptor;
+    typedef boost::queue<vertex_descriptor> queue_t;
+    queue_t Q;
+    detail::wrap_ref<queue_t> Qref(Q);
+
+    breadth_first_visit
+      (ng, s,
+       choose_param(get_param(params, buffer_param_t()), Qref).ref,
+       choose_param(get_param(params, graph_visitor),
+                    make_bfs_visitor(null_visitor())),
+       choose_pmap(get_param(params, vertex_color), ng, vertex_color)
+       );
+  }
+
+} // namespace boost
+
+#endif // BOOST_GRAPH_BREADTH_FIRST_SEARCH_HPP
+