1 //=======================================================================
2 // Copyright 2001 Jeremy G. Siek, Andrew Lumsdaine, Lie-Quan Lee,
4 // Distributed under the Boost Software License, Version 1.0. (See
5 // accompanying file LICENSE_1_0.txt or copy at
6 // http://www.boost.org/LICENSE_1_0.txt)
7 //=======================================================================
8 #include <boost/config.hpp>
12 #include <boost/graph/graph_traits.hpp>
13 #include <boost/graph/adjacency_list.hpp>
14 #include <boost/graph/dijkstra_shortest_paths.hpp>
15 #include <boost/property_map/property_map.hpp>
17 using namespace boost;
22 typedef adjacency_list < listS, vecS, directedS,
23 no_property, property < edge_weight_t, int > > graph_t;
24 typedef graph_traits < graph_t >::vertex_descriptor vertex_descriptor;
25 typedef std::pair<int, int> Edge;
27 const int num_nodes = 5;
28 enum nodes { A, B, C, D, E };
29 char name[] = "ABCDE";
30 Edge edge_array[] = { Edge(A, C), Edge(B, B), Edge(B, D), Edge(B, E),
31 Edge(C, B), Edge(C, D), Edge(D, E), Edge(E, A), Edge(E, B)
33 int weights[] = { 1, 2, 1, 2, 7, 3, 1, 1, 1 };
34 int num_arcs = sizeof(edge_array) / sizeof(Edge);
35 graph_t g(edge_array, edge_array + num_arcs, weights, num_nodes);
36 property_map<graph_t, edge_weight_t>::type weightmap = get(edge_weight, g);
37 std::vector<vertex_descriptor> p(num_vertices(g));
38 std::vector<int> d(num_vertices(g));
39 vertex_descriptor s = vertex(A, g);
41 dijkstra_shortest_paths(g, s,
42 predecessor_map(boost::make_iterator_property_map(p.begin(), get(boost::vertex_index, g))).
43 distance_map(boost::make_iterator_property_map(d.begin(), get(boost::vertex_index, g))));
45 std::cout << "distances and parents:" << std::endl;
46 graph_traits < graph_t >::vertex_iterator vi, vend;
47 for (boost::tie(vi, vend) = vertices(g); vi != vend; ++vi) {
48 std::cout << "distance(" << name[*vi] << ") = " << d[*vi] << ", ";
49 std::cout << "parent(" << name[*vi] << ") = " << name[p[*vi]] << std::
52 std::cout << std::endl;
54 std::ofstream dot_file("figs/dijkstra-eg.dot");
56 dot_file << "digraph D {\n"
59 << " ratio=\"fill\"\n"
60 << " edge[style=\"bold\"]\n" << " node[shape=\"circle\"]\n";
62 graph_traits < graph_t >::edge_iterator ei, ei_end;
63 for (boost::tie(ei, ei_end) = edges(g); ei != ei_end; ++ei) {
64 graph_traits < graph_t >::edge_descriptor e = *ei;
65 graph_traits < graph_t >::vertex_descriptor
66 u = source(e, g), v = target(e, g);
67 dot_file << name[u] << " -> " << name[v]
68 << "[label=\"" << get(weightmap, e) << "\"";
70 dot_file << ", color=\"black\"";
72 dot_file << ", color=\"grey\"";