75 lines
2.0 KiB
C++
75 lines
2.0 KiB
C++
//=======================================================================
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// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
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// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
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//
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// Distributed under the Boost Software License, Version 1.0. (See
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// accompanying file LICENSE_1_0.txt or copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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//=======================================================================
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#include <boost/config.hpp>
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#include <iostream>
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#include <list>
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#include <algorithm>
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#include <boost/graph/adjacency_list.hpp>
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#include <boost/graph/topological_sort.hpp>
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#include <iterator>
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#include <utility>
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typedef std::pair<std::size_t,std::size_t> Pair;
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/*
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Topological sort example
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The topological sort algorithm creates a linear ordering
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of the vertices such that if edge (u,v) appears in the graph,
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then u comes before v in the ordering.
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Sample output:
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A topological ordering: 2 5 0 1 4 3
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*/
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int
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main(int , char* [])
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{
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//begin
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using namespace boost;
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/* Topological sort will need to color the graph. Here we use an
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internal decorator, so we "property" the color to the graph.
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*/
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typedef adjacency_list<vecS, vecS, directedS,
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property<vertex_color_t, default_color_type> > Graph;
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typedef boost::graph_traits<Graph>::vertex_descriptor Vertex;
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Pair edges[6] = { Pair(0,1), Pair(2,4),
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Pair(2,5),
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Pair(0,3), Pair(1,4),
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Pair(4,3) };
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#if defined(BOOST_MSVC) && BOOST_MSVC <= 1300
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// VC++ can't handle the iterator constructor
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Graph G(6);
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for (std::size_t j = 0; j < 6; ++j)
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add_edge(edges[j].first, edges[j].second, G);
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#else
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Graph G(edges, edges + 6, 6);
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#endif
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boost::property_map<Graph, vertex_index_t>::type id = get(vertex_index, G);
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typedef std::vector< Vertex > container;
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container c;
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topological_sort(G, std::back_inserter(c));
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std::cout << "A topological ordering: ";
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for (container::reverse_iterator ii = c.rbegin();
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ii != c.rend(); ++ii)
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std::cout << id[*ii] << " ";
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std::cout << std::endl;
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return 0;
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}
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