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// Author: Alex Lauser
// Output (Note that 'finish_edge' is never printed):
// The example graph:
// 0 --> 1 2
// 1 --> 2
// 2 --> 0
#include <boost/config.hpp>
#include <iostream>
#include <vector>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/graph_utility.hpp>
template<typename graph_t>
struct TalkativeVisitor
: boost::dfs_visitor<>
{
typedef typename boost::graph_traits<graph_t>::vertex_descriptor vertex_descriptor;
typedef typename boost::graph_traits<graph_t>::edge_descriptor edge_descriptor;
// // Commented out to avoid clutter of the output.
// void discover_vertex(vertex_descriptor u, const graph_t&) { // check!
// std::cout << "discover_vertex: " << u << std::endl;
// }
// void finish_vertex(vertex_descriptor u, const graph_t&) { // check!
// std::cout << "finish_vertex: " << u << std::endl;
// }
// void initialize_vertex(vertex_descriptor u, const graph_t&) { // check!
// std::cout << "initialize_vertex: " << u << std::endl;
// }
// void start_vertex(vertex_descriptor u, const graph_t&) { // check!
// std::cout << "start_vertex: " << u << std::endl;
// }
// void examine_edge(edge_descriptor u, const graph_t&) { // check!
// std::cout << "examine_edge: " << u << std::endl;
// }
// void tree_edge(edge_descriptor u, const graph_t&) { // check!
// std::cout << "tree_edge: " << u << std::endl;
// }
// void back_edge(edge_descriptor u, const graph_t&) { // check!
// std::cout << "back_edge: " << u << std::endl;
// }
// void forward_or_cross_edge(edge_descriptor u, const graph_t&) { // check!
// std::cout << "forward_or_cross_edge: " << u << std::endl;
// }
void finish_edge(edge_descriptor u, const graph_t&) { // uncalled!
std::cout << "finish_edge: " << u << std::endl;
}
};
template <typename t>
std::ostream &operator<<(std::ostream &os, const std::pair<t,t> &x) {
return os << "(" << x.first << ", " << x.second << ")";
}
int main(int, char*[])
{
using namespace boost;
typedef adjacency_list<vecS, vecS, directedS> Graph;
Graph 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, c, G);
add_edge(c, a, G);
add_edge(a, c, G);
std::cout << "The example graph:" << std::endl;
print_graph(G);
std::vector<default_color_type> color(num_vertices(G));
depth_first_search(G, visitor(TalkativeVisitor<Graph>()));
return 0;
}
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