// Output:

// The example graph:
// a --> b 
// b --> a c 
// c --> b 
//
// Vertex a is in component 0 and has root 0
// Vertex b is in component 0 and has root 0
// Vertex c is in component 0 and has root 1


#include <boost/config.hpp>
#include <iostream>
#include <vector>
#include <boost/graph/strong_components.hpp>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/graph_utility.hpp>

int main(int, char*[])
{
  using namespace boost;
  const char* name = "abc";

  adjacency_list<vecS, vecS, directedS> G;

  typedef graph_traits<adjacency_list<vecS, vecS, directedS> >::vertex_descriptor Vertex;
  Vertex a = add_vertex(G);
  Vertex b = add_vertex(G);
  Vertex c = add_vertex(G);
  
  add_edge(a, b, G);
  add_edge(b, a, G);

  add_edge(c, b, G);
  add_edge(b, c, G);
  
  std::cout << "The example graph:" << std::endl;
  print_graph(G, name);
  std::cout << std::endl;
  
  std::vector<int> component(num_vertices(G)), discover_time(num_vertices(G));
  std::vector<default_color_type> color(num_vertices(G));
  std::vector<Vertex> root(num_vertices(G));
  strong_components(G, make_iterator_property_map(component.begin(), get(vertex_index, G)), 
		    root_map(make_iterator_property_map(root.begin(), get(vertex_index, G))).
		    color_map(make_iterator_property_map(color.begin(), get(vertex_index, G))).
		    discover_time_map(make_iterator_property_map(discover_time.begin(), get(vertex_index, G))));
  
  std::vector<int>::size_type i;
  for (i = 0; i != component.size(); ++i)
    std::cout << "Vertex " << name[i]
	      << " is in component " << component[i] 
	      << " and has root " << root[i] << std::endl;
  
  return 0;
}