code:
//=======================================================================
// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
// Copyright 2010 Thomas Claveirole
// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek, Thomas Claveirole
//
// 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_ADJACENCY_LIST_HPP
#define BOOST_GRAPH_ADJACENCY_LIST_HPP

#include <boost/config.hpp>

#include <vector>
#include <list>
#include <set>

#include <boost/unordered_set.hpp>

#include <boost/scoped_ptr.hpp>

#include <boost/graph/graph_traits.hpp>
#include <boost/graph/graph_mutability_traits.hpp>
#include <boost/graph/graph_selectors.hpp>
#include <boost/property_map/property_map.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/and.hpp>
#include <boost/mpl/not.hpp>
#include <boost/mpl/bool.hpp>
#include <boost/graph/detail/edge.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/detail/workaround.hpp>
#include <boost/graph/properties.hpp>
#include <boost/graph/named_graph.hpp>

namespace boost {

  //===========================================================================
  // Selectors for the VertexList and EdgeList template parameters of
  // adjacency_list, and the container_gen traits class which is used
  // to map the selectors to the container type used to implement the
  // graph.

  struct vecS  { };
  struct listS { };
  struct setS { };
  struct mapS  { };
  struct multisetS { };
  struct multimapS { };
  struct hash_setS { };
  struct hash_mapS { };
  struct hash_multisetS { };
  struct hash_multimapS { };

  template <class Selector, class ValueType>
  struct container_gen { };

  template <class ValueType>
  struct container_gen<listS, ValueType> {
    typedef std::list<ValueType> type;
  };

  template <class ValueType>
  struct container_gen<vecS, ValueType> {
    typedef std::vector<ValueType> type;
  };

  template <class ValueType>
  struct container_gen<mapS, ValueType> {
    typedef std::set<ValueType> type;
  };

  template <class ValueType>
  struct container_gen<setS, ValueType> {
    typedef std::set<ValueType> type;
  };

  template <class ValueType>
  struct container_gen<multisetS, ValueType> {
    typedef std::multiset<ValueType> type;
  };

  template <class ValueType>
  struct container_gen<multimapS, ValueType> {
    typedef std::multiset<ValueType> type;
  };

  template <class ValueType>
  struct container_gen<hash_setS, ValueType> {
    typedef boost::unordered_set<ValueType> type;
  };

  template <class ValueType>
  struct container_gen<hash_mapS, ValueType> {
    typedef boost::unordered_set<ValueType> type;
  };

  template <class ValueType>
  struct container_gen<hash_multisetS, ValueType> {
    typedef boost::unordered_multiset<ValueType> type;
  };

  template <class ValueType>
  struct container_gen<hash_multimapS, ValueType> {
    typedef boost::unordered_multiset<ValueType> type;
  };

  template <class StorageSelector>
  struct parallel_edge_traits { };

  template <>
  struct parallel_edge_traits<vecS> {
    typedef allow_parallel_edge_tag type; };

  template <>
  struct parallel_edge_traits<listS> {
    typedef allow_parallel_edge_tag type; };

  template <>
  struct parallel_edge_traits<setS> {
    typedef disallow_parallel_edge_tag type; };

  template <>
  struct parallel_edge_traits<multisetS> {
    typedef allow_parallel_edge_tag type; };

  template <>
  struct parallel_edge_traits<hash_setS> {
    typedef disallow_parallel_edge_tag type;
  };

  // mapS is obsolete, replaced with setS
  template <>
  struct parallel_edge_traits<mapS> {
    typedef disallow_parallel_edge_tag type; };

  template <>
  struct parallel_edge_traits<hash_mapS> {
    typedef disallow_parallel_edge_tag type;
  };

  template <>
  struct parallel_edge_traits<hash_multisetS> {
    typedef allow_parallel_edge_tag type;
  };

  template <>
  struct parallel_edge_traits<hash_multimapS> {
    typedef allow_parallel_edge_tag type;
  };

  namespace detail {
    template <class Directed> struct is_random_access {
      enum { value = false};
      typedef mpl::false_ type;
    };
    template <>
    struct is_random_access<vecS> {
      enum { value = true };
      typedef mpl::true_ type;
    };

  } // namespace detail

  template <typename Selector> struct is_distributed_selector: mpl::false_ {};

  //===========================================================================
  // The adjacency_list_traits class, which provides a way to access
  // some of the associated types of an adjacency_list type without
  // having to first create the adjacency_list type. This is useful
  // when trying to create interior vertex or edge properties who's
  // value type is a vertex or edge descriptor.

  template <class OutEdgeListS = vecS,
            class VertexListS = vecS,
            class DirectedS = directedS,
            class EdgeListS = listS>
  struct adjacency_list_traits
  {
    typedef typename detail::is_random_access<VertexListS>::type
      is_rand_access;
    typedef typename DirectedS::is_bidir_t is_bidir;
    typedef typename DirectedS::is_directed_t is_directed;

    typedef typename mpl::if_<is_bidir,
      bidirectional_tag,
      typename mpl::if_<is_directed,
        directed_tag, undirected_tag
      >::type
    >::type directed_category;

    typedef typename parallel_edge_traits<OutEdgeListS>::type
      edge_parallel_category;

    typedef std::size_t vertices_size_type;
    typedef void* vertex_ptr;
    typedef typename mpl::if_<is_rand_access,
      vertices_size_type, vertex_ptr>::type vertex_descriptor;
    typedef detail::edge_desc_impl<directed_category, vertex_descriptor>
      edge_descriptor;

  private:
    // Logic to figure out the edges_size_type
    struct dummy {};
    typedef typename container_gen<EdgeListS, dummy>::type EdgeContainer;
    typedef typename DirectedS::is_bidir_t BidirectionalT;
    typedef typename DirectedS::is_directed_t DirectedT;
    typedef typename mpl::and_<DirectedT,
      typename mpl::not_<BidirectionalT>::type >::type on_edge_storage;
  public:
    typedef typename mpl::if_<on_edge_storage,
       std::size_t, typename EdgeContainer::size_type
    >::type edges_size_type;

  };

} // namespace boost

#include <boost/graph/detail/adjacency_list.hpp>

namespace boost {

  //===========================================================================
  // The adjacency_list class.
  //

  template <class OutEdgeListS = vecS, // a Sequence or an AssociativeContainer
            class VertexListS = vecS, // a Sequence or a RandomAccessContainer
            class DirectedS = directedS,
            class VertexProperty = no_property,
            class EdgeProperty = no_property,
            class GraphProperty = no_property,
            class EdgeListS = listS>
  class adjacency_list
    : public detail::adj_list_gen<
      adjacency_list<OutEdgeListS,VertexListS,DirectedS,
                     VertexProperty,EdgeProperty,GraphProperty,EdgeListS>,
      VertexListS, OutEdgeListS, DirectedS,
      VertexProperty, EdgeProperty,
      GraphProperty, EdgeListS>::type,
      // Support for named vertices
      public graph::maybe_named_graph<
        adjacency_list<OutEdgeListS,VertexListS,DirectedS,
                       VertexProperty,EdgeProperty,GraphProperty,EdgeListS>,
        typename adjacency_list_traits<OutEdgeListS, VertexListS, DirectedS,
                                       EdgeListS>::vertex_descriptor,
        VertexProperty>
  {
      public:
    typedef GraphProperty graph_property_type;
    typedef typename lookup_one_property<GraphProperty, graph_bundle_t>::type graph_bundled;

    typedef VertexProperty vertex_property_type;
    typedef typename lookup_one_property<VertexProperty, vertex_bundle_t>::type vertex_bundled;

    typedef EdgeProperty edge_property_type;
    typedef typename lookup_one_property<EdgeProperty, edge_bundle_t>::type edge_bundled;

  private:
    typedef adjacency_list self;
    typedef typename detail::adj_list_gen<
      self, VertexListS, OutEdgeListS, DirectedS,
      vertex_property_type, edge_property_type, GraphProperty, EdgeListS
    >::type Base;

  public:
    typedef typename Base::stored_vertex stored_vertex;
    typedef typename Base::vertices_size_type vertices_size_type;
    typedef typename Base::edges_size_type edges_size_type;
    typedef typename Base::degree_size_type degree_size_type;
    typedef typename Base::vertex_descriptor vertex_descriptor;
    typedef typename Base::edge_descriptor edge_descriptor;
    typedef OutEdgeListS out_edge_list_selector;
    typedef VertexListS vertex_list_selector;
    typedef DirectedS directed_selector;
    typedef EdgeListS edge_list_selector;

    adjacency_list(const GraphProperty& p = GraphProperty())
      : m_property(new graph_property_type(p))
    { }

    adjacency_list(const adjacency_list& x)
      : Base(x), m_property(new graph_property_type(*x.m_property))
    { }

    adjacency_list& operator=(const adjacency_list& x) {
      // TBD: probably should give the strong guarantee
      if (&x != this) {
        Base::operator=(x);

        // Copy/swap the ptr since we can't just assign it...
        property_ptr p(new graph_property_type(*x.m_property));
        m_property.swap(p);
      }
      return *this;
    }

    // Required by Mutable Graph
    adjacency_list(vertices_size_type num_vertices,
                          const GraphProperty& p = GraphProperty())
      : Base(num_vertices), m_property(new graph_property_type(p))
    { }

    // Required by Iterator Constructible Graph
    template <class EdgeIterator>
    adjacency_list(EdgeIterator first, EdgeIterator last,
                          vertices_size_type n,
                          edges_size_type = 0,
                          const GraphProperty& p = GraphProperty())
      : Base(n, first, last), m_property(new graph_property_type(p))
    { }

    template <class EdgeIterator, class EdgePropertyIterator>
    adjacency_list(EdgeIterator first, EdgeIterator last,
                          EdgePropertyIterator ep_iter,
                          vertices_size_type n,
                          edges_size_type = 0,
                          const GraphProperty& p = GraphProperty())
      : Base(n, first, last, ep_iter), m_property(new graph_property_type(p))
    { }

    void swap(adjacency_list& x) {
      // Is there a more efficient way to do this?
      adjacency_list tmp(x);
      x = *this;
      *this = tmp;
    }

    void clear()
    {
      this->clearing_graph();
      Base::clear();
    }

#ifndef BOOST_GRAPH_NO_BUNDLED_PROPERTIES
    // Directly access a vertex or edge bundle
    vertex_bundled& operator[](vertex_descriptor v)
    { return get(vertex_bundle, *this)[v]; }

    const vertex_bundled& operator[](vertex_descriptor v) const
    { return get(vertex_bundle, *this)[v]; }

    edge_bundled& operator[](edge_descriptor e)
    { return get(edge_bundle, *this)[e]; }

    const edge_bundled& operator[](edge_descriptor e) const
    { return get(edge_bundle, *this)[e]; }

    graph_bundled& operator[](graph_bundle_t)
    { return get_property(*this); }

    graph_bundled const& operator[](graph_bundle_t) const
    { return get_property(*this); }
#endif

    //  protected:  (would be protected if friends were more portable)
    typedef scoped_ptr<graph_property_type> property_ptr;
    property_ptr  m_property;
  };

#define ADJLIST_PARAMS \
    typename OEL, typename VL, typename D, typename VP, typename EP, \
    typename GP, typename EL
#define ADJLIST adjacency_list<OEL,VL,D,VP,EP,GP,EL>

  template<ADJLIST_PARAMS, typename Tag, typename Value>
  inline void set_property(ADJLIST& g, Tag tag, Value const& value) {
    get_property_value(*g.m_property, tag) = value;
  }

  template<ADJLIST_PARAMS, typename Tag>
  inline typename graph_property<ADJLIST, Tag>::type&
  get_property(ADJLIST& g, Tag tag) {
    return get_property_value(*g.m_property, tag);
  }

  template<ADJLIST_PARAMS, typename Tag>
  inline typename graph_property<ADJLIST, Tag>::type const&
  get_property(ADJLIST const& g, Tag tag) {
    return get_property_value(*g.m_property, tag);
  }

  // dwa 09/25/00 - needed to be more explicit so reverse_graph would work.
  template <class Directed, class Vertex,
      class OutEdgeListS,
      class VertexListS,
      class DirectedS,
      class VertexProperty,
      class EdgeProperty,
      class GraphProperty, class EdgeListS>
  inline Vertex
  source(const detail::edge_base<Directed,Vertex>& e,
         const adjacency_list<OutEdgeListS, VertexListS, DirectedS,
                 VertexProperty, EdgeProperty, GraphProperty, EdgeListS>&)
  {
    return e.m_source;
  }

  template <class Directed, class Vertex, class OutEdgeListS,
      class VertexListS, class DirectedS, class VertexProperty,
      class EdgeProperty, class GraphProperty, class EdgeListS>
  inline Vertex
  target(const detail::edge_base<Directed,Vertex>& e,
         const adjacency_list<OutEdgeListS, VertexListS, DirectedS,
              VertexProperty, EdgeProperty, GraphProperty, EdgeListS>&)
  {
    return e.m_target;
  }

// Mutability Traits
template <ADJLIST_PARAMS>
struct graph_mutability_traits<ADJLIST> {
    typedef mutable_property_graph_tag category;
};

// Can't remove vertices from adjacency lists with VL==vecS
template <typename OEL, typename D, typename VP, typename EP, typename GP, typename EL>
struct graph_mutability_traits< adjacency_list<OEL,vecS,D,VP,EP,GP,EL> > {
    typedef add_only_property_graph_tag category;
};
#undef ADJLIST_PARAMS
#undef ADJLIST

} // namespace boost

#endif // BOOST_GRAPH_ADJACENCY_LIST_HPP


code:
//
//=======================================================================
// 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>
#include <boost/graph/overloading.hpp>
#include <boost/graph/graph_concepts.hpp>
#include <boost/graph/two_bit_color_map.hpp>
#include <boost/concept/assert.hpp>

#ifdef BOOST_GRAPH_USE_MPI
#include <boost/graph/distributed/concepts.hpp>
#endif // BOOST_GRAPH_USE_MPI

namespace boost {

  template <class Visitor, class Graph>
  struct BFSVisitorConcept {
    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.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;
  };

  // Multiple-source version
  template <class IncidenceGraph, class Buffer, class BFSVisitor,
            class ColorMap, class SourceIterator>
  void breadth_first_visit
    (const IncidenceGraph& g,
     SourceIterator sources_begin, SourceIterator sources_end,
     Buffer& Q, BFSVisitor vis, ColorMap color)
  {
    BOOST_CONCEPT_ASSERT(( IncidenceGraphConcept<IncidenceGraph> ));
    typedef graph_traits<IncidenceGraph> GTraits;
    typedef typename GTraits::vertex_descriptor Vertex;
    BOOST_CONCEPT_ASSERT(( BFSVisitorConcept<BFSVisitor, IncidenceGraph> ));
    BOOST_CONCEPT_ASSERT(( ReadWritePropertyMapConcept<ColorMap, Vertex> ));
    typedef typename property_traits<ColorMap>::value_type ColorValue;
    typedef color_traits<ColorValue> Color;
    typename GTraits::out_edge_iterator ei, ei_end;

    for (; sources_begin != sources_end; ++sources_begin) {
      Vertex s = *sources_begin;
      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 (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);
          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

  // Single-source version
  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)
  {
    typename graph_traits<IncidenceGraph>::vertex_descriptor sources[1] = {s};
    breadth_first_visit(g, sources, sources + 1, Q, vis, color);
  }

  template <class VertexListGraph, class SourceIterator,
            class Buffer, class BFSVisitor,
            class ColorMap>
  void breadth_first_search
    (const VertexListGraph& g,
     SourceIterator sources_begin, SourceIterator sources_end,
     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 (boost::tie(i, i_end) = vertices(g); i != i_end; ++i) {
      vis.initialize_vertex(*i, g);
      put(color, *i, Color::white());
    }
    breadth_first_visit(g, sources_begin, sources_end, Q, vis, color);
  }

  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)
  {
    typename graph_traits<VertexListGraph>::vertex_descriptor sources[1] = {s};
    breadth_first_search(g, sources, sources + 1, Q, vis, color);
  }

  namespace graph { struct bfs_visitor_event_not_overridden {}; }

  template <class Visitors = null_visitor>
  class bfs_visitor {
  public:
    bfs_visitor() { }
    bfs_visitor(Visitors vis) : m_vis(vis) { }

    template <class Vertex, class Graph>
    graph::bfs_visitor_event_not_overridden
    initialize_vertex(Vertex u, Graph& g)
    {
      invoke_visitors(m_vis, u, g, ::boost::on_initialize_vertex());
      return graph::bfs_visitor_event_not_overridden();
    }

    template <class Vertex, class Graph>
    graph::bfs_visitor_event_not_overridden
    discover_vertex(Vertex u, Graph& g)
    {
      invoke_visitors(m_vis, u, g, ::boost::on_discover_vertex());
      return graph::bfs_visitor_event_not_overridden();
    }

    template <class Vertex, class Graph>
    graph::bfs_visitor_event_not_overridden
    examine_vertex(Vertex u, Graph& g)
    {
      invoke_visitors(m_vis, u, g, ::boost::on_examine_vertex());
      return graph::bfs_visitor_event_not_overridden();
    }

    template <class Edge, class Graph>
    graph::bfs_visitor_event_not_overridden
    examine_edge(Edge e, Graph& g)
    {
      invoke_visitors(m_vis, e, g, ::boost::on_examine_edge());
      return graph::bfs_visitor_event_not_overridden();
    }

    template <class Edge, class Graph>
    graph::bfs_visitor_event_not_overridden
    tree_edge(Edge e, Graph& g)
    {
      invoke_visitors(m_vis, e, g, ::boost::on_tree_edge());
      return graph::bfs_visitor_event_not_overridden();
    }

    template <class Edge, class Graph>
    graph::bfs_visitor_event_not_overridden
    non_tree_edge(Edge e, Graph& g)
    {
      invoke_visitors(m_vis, e, g, ::boost::on_non_tree_edge());
      return graph::bfs_visitor_event_not_overridden();
    }

    template <class Edge, class Graph>
    graph::bfs_visitor_event_not_overridden
    gray_target(Edge e, Graph& g)
    {
      invoke_visitors(m_vis, e, g, ::boost::on_gray_target());
      return graph::bfs_visitor_event_not_overridden();
    }

    template <class Edge, class Graph>
    graph::bfs_visitor_event_not_overridden
    black_target(Edge e, Graph& g)
    {
      invoke_visitors(m_vis, e, g, ::boost::on_black_target());
      return graph::bfs_visitor_event_not_overridden();
    }

    template <class Vertex, class Graph>
    graph::bfs_visitor_event_not_overridden
    finish_vertex(Vertex u, Graph& g)
    {
      invoke_visitors(m_vis, u, g, ::boost::on_finish_vertex());
      return graph::bfs_visitor_event_not_overridden();
    }

    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,
       boost::mpl::false_)
    {
      typedef graph_traits<VertexListGraph> Traits;
      // Buffer default
      typedef typename Traits::vertex_descriptor Vertex;
      typedef boost::queue<Vertex> queue_t;
      queue_t Q;
      breadth_first_search
        (g, s,
         choose_param(get_param(params, buffer_param_t()), boost::ref(Q)).get(),
         vis, color);
    }

#ifdef BOOST_GRAPH_USE_MPI
    template <class DistributedGraph, class ColorMap, class BFSVisitor,
              class P, class T, class R>
    void bfs_helper
      (DistributedGraph& g,
       typename graph_traits<DistributedGraph>::vertex_descriptor s,
       ColorMap color,
       BFSVisitor vis,
       const bgl_named_params<P, T, R>& params,
       boost::mpl::true_);
#endif // BOOST_GRAPH_USE_MPI

    //-------------------------------------------------------------------------
    // 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,
           boost::mpl::bool_<
             boost::is_base_and_derived<
               distributed_graph_tag,
               typename graph_traits<VertexListGraph>::traversal_category>::value>());
      }
    };

    template <>
    struct bfs_dispatch<param_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,
       param_not_found)
      {
        null_visitor null_vis;

        bfs_helper
          (g, s,
           make_two_bit_color_map
           (num_vertices(g),
            choose_const_pmap(get_param(params, vertex_index),
                              g, vertex_index)),
           choose_param(get_param(params, graph_visitor),
                        make_bfs_visitor(null_vis)),
           params,
           boost::mpl::bool_<
             boost::is_base_and_derived<
               distributed_graph_tag,
               typename graph_traits<VertexListGraph>::traversal_category>::value>());
      }
    };

  } // namespace detail

#if 1
  // 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 get_param_type< vertex_color_t, bgl_named_params<P,T,R> >::type C;
    detail::bfs_dispatch<C>::apply(ng, s, params,
                                   get_param(params, vertex_color));
  }
#endif

  // 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;

    breadth_first_visit
      (ng, s,
       choose_param(get_param(params, buffer_param_t()), boost::ref(Q)).get(),
       choose_param(get_param(params, graph_visitor),
                    make_bfs_visitor(null_visitor())),
       choose_pmap(get_param(params, vertex_color), ng, vertex_color)
       );
  }

  namespace graph {
    namespace detail {
      template <typename Graph, typename Source>
      struct breadth_first_search_impl {
        typedef void result_type;
        template <typename ArgPack>
        void operator()(const Graph& g, const Source& source, const ArgPack& arg_pack) {
          using namespace boost::graph::keywords;
          typename boost::graph_traits<Graph>::vertex_descriptor sources[1] = {source};
          boost::queue<typename boost::graph_traits<Graph>::vertex_descriptor> Q;
          boost::breadth_first_search(g,
                                      &sources[0],
                                      &sources[1],
                                      boost::unwrap_ref(arg_pack[_buffer | boost::ref(Q)]),
                                      arg_pack[_visitor | make_bfs_visitor(null_visitor())],
                                      boost::detail::make_color_map_from_arg_pack(g, arg_pack));
        }
      };
    }
    BOOST_GRAPH_MAKE_FORWARDING_FUNCTION(breadth_first_search, 2, 4)
  }

#if 0
  // Named Parameter Variant
  BOOST_GRAPH_MAKE_OLD_STYLE_PARAMETER_FUNCTION(breadth_first_search, 2)
#endif

} // namespace boost

#ifdef BOOST_GRAPH_USE_MPI
#  include <boost/graph/distributed/breadth_first_search.hpp>
#endif

#endif // BOOST_GRAPH_BREADTH_FIRST_SEARCH_HPP

license: mit


code:
//            Copyright Daniel Trebbien 2010.
// Distributed under the Boost Software License, Version 1.0.
//   (See accompanying file LICENSE_1_0.txt or the copy at
//         http://www.boost.org/LICENSE_1_0.txt)

#ifndef BOOST_GRAPH_BUFFER_CONCEPTS_HPP
#define BOOST_GRAPH_BUFFER_CONCEPTS_HPP 1
#include <boost/concept_check.hpp>
#include <boost/property_map/property_map.hpp>
#include <boost/typeof/typeof.hpp>
#include <boost/type_traits/add_const.hpp>
#include <boost/type_traits/add_reference.hpp>
#include <boost/type_traits/remove_reference.hpp>

#include <boost/concept/detail/concept_def.hpp>
namespace boost {

  BOOST_concept(Buffer, (B))
  {
    typedef typename B::value_type value_type;
    typedef typename B::size_type size_type;

    BOOST_CONCEPT_USAGE(Buffer) {
      typedef typename boost::add_reference<value_type>::type reference;

      BOOST_CONCEPT_ASSERT((Assignable<value_type>));

      buf.push(g_ct);
      buf.pop();
      reference t = buf.top();
      boost::ignore_unused_variable_warning(t);
    }

    void const_constraints(const B& cbuf) {
      typedef typename boost::add_const<typename boost::remove_reference<value_type>::type>::type& const_reference;

      const_reference ct = cbuf.top();
      s = cbuf.size();
      if (cbuf.empty())
        dummy = __LINE__;
    }

    int dummy;

    static const value_type g_ct;
    size_type s;
    B buf;
  };

  BOOST_concept(UpdatableQueue, (Q))
    : Buffer<Q>
  {
    BOOST_CONCEPT_USAGE(UpdatableQueue) {
      q.update(g_ct);
    }

    void const_constraints(const Q& cq) {
      if (cq.contains(g_ct))
        dummy = __LINE__;
    }

    int dummy;

    static const typename Buffer<Q>::value_type g_ct;
    Q q;
  };

  BOOST_concept(KeyedUpdatableQueue, (Q))
    : UpdatableQueue<Q>
  {
    typedef typename Q::key_type key_type;
    typedef typename Q::key_map key_map;

    BOOST_CONCEPT_USAGE(KeyedUpdatableQueue) {
      BOOST_CONCEPT_ASSERT((boost::ReadWritePropertyMapConcept<key_map, typename Buffer<Q>::value_type>));
    }

    void const_constraints(const Q& cq) {
      km = cq.keys();
      k = get(km, g_ct);
    }

    static const typename Buffer<Q>::value_type g_ct;
    key_type k;
    key_map km;
    Q q;
  };

} // end `namespace boost`
#include <boost/concept/detail/concept_undef.hpp>

#endif // !BOOST_GRAPH_BUFFER_CONCEPTS_HPP


code:
//
//=======================================================================
// 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_DETAIL_ADJ_LIST_EDGE_ITERATOR_HPP
#define BOOST_GRAPH_DETAIL_ADJ_LIST_EDGE_ITERATOR_HPP

#include <iterator>
#include <utility>
#include <boost/detail/workaround.hpp>

#if BOOST_WORKAROUND( __IBMCPP__, <= 600 )
#  define BOOST_GRAPH_NO_OPTIONAL
#endif

#ifdef BOOST_GRAPH_NO_OPTIONAL
#  define BOOST_GRAPH_MEMBER .
#else
#  define BOOST_GRAPH_MEMBER ->
#  include <boost/optional.hpp>
#endif // ndef BOOST_GRAPH_NO_OPTIONAL

namespace boost {

  namespace detail {

    template <class VertexIterator, class OutEdgeIterator, class Graph>
    class adj_list_edge_iterator {
      typedef adj_list_edge_iterator self;
    public:
      typedef std::forward_iterator_tag iterator_category;
      typedef typename OutEdgeIterator::value_type value_type;
      typedef typename OutEdgeIterator::reference  reference;
      typedef typename OutEdgeIterator::pointer    pointer;
      typedef typename OutEdgeIterator::difference_type difference_type;
      typedef difference_type distance_type;

      inline adj_list_edge_iterator() {}

      inline adj_list_edge_iterator(const self& x)
      : vBegin(x.vBegin), vCurr(x.vCurr), vEnd(x.vEnd),
        edges(x.edges), m_g(x.m_g) { }

      template <class G>
      inline adj_list_edge_iterator(VertexIterator b,
                                    VertexIterator c,
                                    VertexIterator e,
                                    const G& g)
        : vBegin(b), vCurr(c), vEnd(e), m_g(&g) {
        if ( vCurr != vEnd ) {
          while ( vCurr != vEnd && out_degree(*vCurr, *m_g) == 0 )
            ++vCurr;
          if ( vCurr != vEnd )
            edges = out_edges(*vCurr, *m_g);
        }
      }

      /*Note:
        In the directed graph cases, it is fine.
        For undirected graphs, one edge go through twice.
      */
      inline self& operator++() {
        ++edges BOOST_GRAPH_MEMBER first;
        if (edges BOOST_GRAPH_MEMBER first == edges BOOST_GRAPH_MEMBER second)
        {
          ++vCurr;
          while ( vCurr != vEnd && out_degree(*vCurr, *m_g) == 0 )
            ++vCurr;
          if ( vCurr != vEnd )
            edges = out_edges(*vCurr, *m_g);
        }
        return *this;
      }
      inline self operator++(int) {
        self tmp = *this;
        ++(*this);
        return tmp;
      }
      inline value_type operator*() const
      { return *edges BOOST_GRAPH_MEMBER first; }
      inline bool operator==(const self& x) const {
        return vCurr == x.vCurr
          && (vCurr == vEnd
              || edges BOOST_GRAPH_MEMBER first == x.edges BOOST_GRAPH_MEMBER first);
      }
      inline bool operator!=(const self& x) const {
        return vCurr != x.vCurr
          || (vCurr != vEnd
              && edges BOOST_GRAPH_MEMBER first != x.edges BOOST_GRAPH_MEMBER first);
      }
    protected:
      VertexIterator vBegin;
      VertexIterator vCurr;
      VertexIterator vEnd;

#ifdef BOOST_GRAPH_NO_OPTIONAL
      std::pair<OutEdgeIterator, OutEdgeIterator> edges;
#else
      boost::optional<std::pair<OutEdgeIterator, OutEdgeIterator> >
        edges;
#endif // ndef BOOST_GRAPH_NO_OPTIONAL
      const Graph* m_g;
    };

  } // namespace detail

}

#undef BOOST_GRAPH_MEMBER

#endif // BOOST_GRAPH_DETAIL_ADJ_LIST_EDGE_ITERATOR_HPP