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- //=======================================================================
- // Copyright 1997-2001 University of Notre Dame.
- // Authors: 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)
- //=======================================================================
- #error "This example appears to be incorrect; it uses edge weights that are smaller than 0 using the comparison operator passed to Dijkstra's algorithm, which is not allowed."
- #include <boost/config.hpp>
- #include <iostream>
- #include <boost/graph/graph_traits.hpp>
- #include <boost/graph/graph_utility.hpp>
- #include <boost/graph/adjacency_list.hpp>
- #include <boost/graph/dijkstra_shortest_paths.hpp>
- #include <boost/graph/visitors.hpp>
- #include <boost/graph/transpose_graph.hpp>
- /* Output:
- distances from start vertex:
- distance(a) = 0
- distance(b) = 3
- distance(c) = 1
- distance(d) = 3
- distance(e) = 3
- min-max paths tree
- a --> c
- b -->
- c --> d
- d --> e
- e --> b
- */
- int
- main(int , char* [])
- {
- using namespace boost;
- typedef adjacency_list<listS, vecS, directedS,
- no_property, property<edge_weight_t, int> > Graph;
- typedef graph_traits<Graph>::vertex_descriptor Vertex;
- typedef std::pair<int,int> E;
- const char name[] = "abcdef";
- const int num_nodes = 6;
- E edges[] = { E(0,2), E(1,1), E(1,3), E(1,4), E(2,1), E(2,3),
- E(3,4), E(4,0), E(4,1) };
- int weights[] = { 1, 2, 1, 2, 7, 3, 1, 1, 1};
- const int n_edges = sizeof(edges)/sizeof(E);
- #if defined(BOOST_MSVC) && BOOST_MSVC <= 1300
- // VC++ can't handle iterator constructors
- Graph G(num_nodes);
- property_map<Graph, edge_weight_t>::type weightmap = get(edge_weight, G);
- for (std::size_t j = 0; j < sizeof(edges) / sizeof(E); ++j) {
- graph_traits<Graph>::edge_descriptor e; bool inserted;
- boost::tie(e, inserted) = add_edge(edges[j].first, edges[j].second, G);
- weightmap[e] = weights[j];
- }
- #else
- Graph G(edges, edges + n_edges, weights, num_nodes);
- property_map<Graph, edge_weight_t>::type weightmap = get(edge_weight, G);
- #endif
- std::vector<Vertex> p(num_vertices(G));
- std::vector<int> d(num_vertices(G));
- Vertex s = *(vertices(G).first);
- #if defined(BOOST_MSVC) && BOOST_MSVC <= 1300
- dijkstra_shortest_paths
- (G, s, &p[0], &d[0], weightmap, get(vertex_index, G),
- std::greater<int>(), closed_plus<int>(), (std::numeric_limits<int>::max)(), 0,
- default_dijkstra_visitor());
- #else
- dijkstra_shortest_paths
- (G, s, distance_map(&d[0]).
- predecessor_map(&p[0]).
- distance_compare(std::greater<int>()));
- #endif
- std::cout << "distances from start vertex:" << std::endl;
- graph_traits<Graph>::vertex_iterator vi, vend;
- for(boost::tie(vi,vend) = vertices(G); vi != vend; ++vi)
- std::cout << "distance(" << name[*vi] << ") = " << d[*vi] << std::endl;
- std::cout << std::endl;
- std::cout << "min-max paths tree" << std::endl;
- adjacency_list<> tree(num_nodes);
-
- for(boost::tie(vi,vend) = vertices(G); vi != vend; ++vi)
- if (*vi != p[*vi])
- add_edge(p[*vi], *vi, tree);
- print_graph(tree, name);
- return 0;
- }
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