// Copyright (c) Jeremy Siek 2001
// Copyright (c) Douglas Gregor 2004
//
// 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)
// NOTE: this final is generated by libs/graph/doc/biconnected_components.w
#ifndef BOOST_GRAPH_BICONNECTED_COMPONENTS_HPP
#define BOOST_GRAPH_BICONNECTED_COMPONENTS_HPP
#include <stack>
#include <vector>
#include <algorithm> // for std::min and std::max
#include <boost/config.hpp>
#include <boost/limits.hpp>
#include <boost/graph/graph_traits.hpp>
#include <boost/graph/graph_concepts.hpp>
#include <boost/property_map.hpp>
#include <boost/graph/depth_first_search.hpp>
#include <boost/graph/graph_utility.hpp>
namespace boost
{
namespace detail
{
template<typename ComponentMap, typename DiscoverTimeMap,
typename LowPointMap, typename PredecessorMap,
typename OutputIterator, typename Stack>
struct biconnected_components_visitor : public dfs_visitor<>
{
biconnected_components_visitor
(ComponentMap comp, std::size_t& c, DiscoverTimeMap dtm,
std::size_t& dfs_time, LowPointMap lowpt, PredecessorMap pred,
OutputIterator out, Stack& S)
: comp(comp), c(c), dtm(dtm), dfs_time(dfs_time), lowpt(lowpt),
pred(pred), out(out), S(S) { }
template <typename Vertex, typename Graph>
void start_vertex(const Vertex& u, Graph&)
{
put(pred, u, u);
}
template <typename Vertex, typename Graph>
void discover_vertex(const Vertex& u, Graph&)
{
put(dtm, u, ++dfs_time);
put(lowpt, u, get(dtm, u));
}
template <typename Edge, typename Graph>
void tree_edge(const Edge& e, Graph& g)
{
S.push(e);
put(pred, target(e, g), source(e, g));
}
template <typename Edge, typename Graph>
void back_edge(const Edge& e, Graph& g)
{
BOOST_USING_STD_MIN();
if ( target(e, g) != get(pred, source(e, g)) ) {
S.push(e);
put(lowpt, source(e, g),
min BOOST_PREVENT_MACRO_SUBSTITUTION(get(lowpt, source(e, g)),
get(dtm, target(e, g))));
}
}
template <typename Vertex, typename Graph>
void finish_vertex(const Vertex& u, Graph& g)
{
BOOST_USING_STD_MIN();
Vertex parent = get(pred, u);
bool is_art_point = false;
if ( get(dtm, parent) > get(dtm, u) ) {
parent = get(pred, parent);
is_art_point = true;
}
if ( parent == u ) { // at top
if ( get(dtm, u) + 1 == get(dtm, get(pred, u)) )
is_art_point = false;
} else {
put(lowpt, parent,
min BOOST_PREVENT_MACRO_SUBSTITUTION(get(lowpt, parent),
get(lowpt, u)));
if (get(lowpt, u) >= get(dtm, parent)) {
if ( get(dtm, parent) > get(dtm, get(pred, parent)) ) {
put(pred, u, get(pred, parent));
put(pred, parent, u);
}
while ( get(dtm, source(S.top(), g)) >= get(dtm, u) ) {
put(comp, S.top(), c);
S.pop();
}
put(comp, S.top(), c);
S.pop();
++c;
if ( S.empty() ) {
put(pred, u, parent);
put(pred, parent, u);
}
}
}
if ( is_art_point )
*out++ = u;
}
ComponentMap comp;
std::size_t& c;
DiscoverTimeMap dtm;
std::size_t& dfs_time;
LowPointMap lowpt;
PredecessorMap pred;
OutputIterator out;
Stack& S;
};
} // namespace detail
template<typename Graph, typename ComponentMap, typename OutputIterator,
typename DiscoverTimeMap, typename LowPointMap,
typename PredecessorMap, typename VertexIndexMap>
std::pair<std::size_t, OutputIterator>
biconnected_components(const Graph & g, ComponentMap comp,
OutputIterator out, DiscoverTimeMap discover_time,
LowPointMap lowpt, PredecessorMap pred,
VertexIndexMap index_map)
{
typedef typename graph_traits<Graph>::vertex_descriptor vertex_t;
typedef typename graph_traits<Graph>::edge_descriptor edge_t;
function_requires<VertexListGraphConcept<Graph> >();
function_requires<IncidenceGraphConcept<Graph> >();
function_requires<WritablePropertyMapConcept<ComponentMap, edge_t> >();
function_requires<ReadWritePropertyMapConcept<DiscoverTimeMap,
vertex_t> >();
function_requires<ReadWritePropertyMapConcept<LowPointMap, vertex_t > >();
function_requires<ReadWritePropertyMapConcept<PredecessorMap,
vertex_t> >();
std::size_t num_components = 0;
std::size_t dfs_time = 0;
std::stack < edge_t > S;
detail::biconnected_components_visitor<ComponentMap, DiscoverTimeMap,
LowPointMap, PredecessorMap, OutputIterator, std::stack<edge_t> >
vis(comp, num_components, discover_time, dfs_time, lowpt, pred, out, S);
depth_first_search(g, visitor(vis).vertex_index_map(index_map));
return std::pair<std::size_t, OutputIterator>(num_components, vis.out);
}
template<typename Graph, typename ComponentMap, typename OutputIterator,
typename DiscoverTimeMap, typename LowPointMap,
typename VertexIndexMap>
std::pair<std::size_t, OutputIterator>
biconnected_components(const Graph & g, ComponentMap comp,
OutputIterator out, DiscoverTimeMap discover_time,
LowPointMap lowpt, VertexIndexMap index_map)
{
typedef typename graph_traits<Graph>::vertex_descriptor vertex_t;
std::vector<vertex_t> pred(num_vertices(g));
vertex_t vert = graph_traits<Graph>::null_vertex();
return biconnected_components
(g, comp, out, discover_time, lowpt,
make_iterator_property_map(pred.begin(), index_map, vert),
index_map);
}
template<typename Graph, typename ComponentMap, typename OutputIterator,
typename VertexIndexMap>
std::pair<std::size_t, OutputIterator>
biconnected_components(const Graph& g, ComponentMap comp, OutputIterator out,
VertexIndexMap index_map)
{
typedef typename graph_traits<Graph>::vertex_descriptor vertex_t;
typedef typename graph_traits<Graph>::vertices_size_type
vertices_size_type;
std::vector<vertices_size_type> discover_time(num_vertices(g));
std::vector<vertices_size_type> lowpt(num_vertices(g));
vertices_size_type vst(0);
return biconnected_components
(g, comp, out,
make_iterator_property_map(discover_time.begin(), index_map, vst),
make_iterator_property_map(lowpt.begin(), index_map, vst),
index_map);
}
template < typename Graph, typename ComponentMap, typename OutputIterator>
std::pair<std::size_t, OutputIterator>
biconnected_components(const Graph& g, ComponentMap comp, OutputIterator out)
{
return biconnected_components(g, comp, out, get(vertex_index, g));
}
namespace graph_detail {
struct dummy_output_iterator
{
typedef std::output_iterator_tag iterator_category;
typedef void value_type;
typedef void pointer;
typedef void difference_type;
struct reference {
template<typename T>
reference& operator=(const T&) { return *this; }
};
reference operator*() const { return reference(); }
dummy_output_iterator& operator++() { return *this; }
dummy_output_iterator operator++(int) { return *this; }
};
} // end namespace graph_detail
template <typename Graph, typename ComponentMap>
std::size_t
biconnected_components(const Graph& g, ComponentMap comp)
{
return biconnected_components(g, comp,
graph_detail::dummy_output_iterator()).first;
}
template<typename Graph, typename OutputIterator, typename VertexIndexMap>
OutputIterator
articulation_points(const Graph& g, OutputIterator out,
VertexIndexMap index_map)
{
return biconnected_components(g, dummy_property_map(), out,
index_map).second;
}
template<typename Graph, typename OutputIterator>
OutputIterator
articulation_points(const Graph& g, OutputIterator out)
{
return biconnected_components(g, dummy_property_map(), out,
get(vertex_index, g)).second;
}
} // namespace boost
#endif /* BOOST_GRAPH_BICONNECTED_COMPONENTS_HPP */