Edit: /usr/include/boost/graph/breadth_first_search.hpp (14751B)
//
//=======================================================================
// 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
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include BOOST_GRAPH_MPI_INCLUDE()
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
#include BOOST_GRAPH_MPI_INCLUDE()
#endif // BOOST_GRAPH_BREADTH_FIRST_SEARCH_HPP