//======================================================================= // Copyright 2001 University of Notre Dame. // Author: Jeremy G. Siek // // 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) //======================================================================= /* Sample output: filtered edge set: (A,B) (C,D) (D,B) filtered out-edges: A --> B B --> C --> D D --> B E --> */ #include <boost/config.hpp> #include <iostream> #include <boost/graph/adjacency_list.hpp> #include <boost/graph/filtered_graph.hpp> #include <boost/graph/graph_utility.hpp> template <typename EdgeWeightMap> struct positive_edge_weight { positive_edge_weight() { } positive_edge_weight(EdgeWeightMap weight) : m_weight(weight) { } template <typename Edge> bool operator()(const Edge& e) const { return 0 < boost::get(m_weight, e); } EdgeWeightMap m_weight; }; int main() { using namespace boost; typedef adjacency_list<multisetS, vecS, directedS, no_property, property<edge_weight_t, int> > Graph; typedef property_map<Graph, edge_weight_t>::type EdgeWeightMap; enum { A, B, C, D, E, N }; const char* name = "ABCDE"; Graph g(N); add_edge(A, B, 2, g); add_edge(A, C, 0, g); add_edge(C, D, 1, g); add_edge(C, D, 0, g); add_edge(C, D, 3, g); add_edge(C, E, 0, g); add_edge(D, B, 3, g); add_edge(E, C, 0, g); EdgeWeightMap weight = get(edge_weight, g); std::cout << "unfiltered edge_range(C,D)\n"; graph_traits<Graph>::out_edge_iterator f, l; for (tie(f, l) = edge_range(C, D, g); f != l; ++f) std::cout << name[source(*f, g)] << " --" << weight[*f] << "-> " << name[target(*f, g)] << "\n"; positive_edge_weight<EdgeWeightMap> filter(weight); typedef filtered_graph<Graph, positive_edge_weight<EdgeWeightMap> > FGraph; FGraph fg(g, filter); std::cout << "filtered edge_range(C,D)\n"; graph_traits<FGraph>::out_edge_iterator first, last; for (tie(first, last) = edge_range(C, D, fg); first != last; ++first) std::cout << name[source(*first, fg)] << " --" << weight[*first] << "-> " << name[target(*first, fg)] << "\n"; return 0; }