Boost C++ Libraries

libs/graph/example/biconnected_components.cpp

//=======================================================================
// Copyright 2001 Jeremy G. Siek, Andrew Lumsdaine, Lie-Quan Lee,
//
// 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)
//=======================================================================
#include <boost/config.hpp>
#include <vector>
#include <list>
#include <boost/graph/biconnected_components.hpp>
#include <boost/graph/adjacency_list.hpp>
#include <iterator>
#include <iostream>

namespace boost
{
struct edge_component_t
{
    enum
    {
        num = 555
    };
    typedef edge_property_tag kind;
} edge_component;
}

int main()
{
    using namespace boost;
    typedef adjacency_list< vecS, vecS, undirectedS, no_property,
        property< edge_component_t, std::size_t > >
        graph_t;
    typedef graph_traits< graph_t >::vertex_descriptor vertex_t;
    graph_t g(9);
    add_edge(0, 5, g);
    add_edge(0, 1, g);
    add_edge(0, 6, g);
    add_edge(1, 2, g);
    add_edge(1, 3, g);
    add_edge(1, 4, g);
    add_edge(2, 3, g);
    add_edge(4, 5, g);
    add_edge(6, 8, g);
    add_edge(6, 7, g);
    add_edge(7, 8, g);

    property_map< graph_t, edge_component_t >::type component
        = get(edge_component, g);

    std::size_t num_comps = biconnected_components(g, component);
    std::cerr << "Found " << num_comps << " biconnected components.\n";

    std::vector< vertex_t > art_points;
    articulation_points(g, std::back_inserter(art_points));
    std::cerr << "Found " << art_points.size() << " articulation points.\n";

    std::cout << "graph A {\n"
              << "  node[shape=\"circle\"]\n";

    for (std::size_t i = 0; i < art_points.size(); ++i)
    {
        std::cout << (char)(art_points[i] + 'A')
                  << " [ style=\"filled\", fillcolor=\"red\" ];" << std::endl;
    }

    graph_traits< graph_t >::edge_iterator ei, ei_end;
    for (boost::tie(ei, ei_end) = edges(g); ei != ei_end; ++ei)
        std::cout << (char)(source(*ei, g) + 'A') << " -- "
                  << (char)(target(*ei, g) + 'A') << "[label=\""
                  << component[*ei] << "\"]\n";
    std::cout << "}\n";

    return 0;
}