ceph/src/boost/libs/graph/example/push-relabel-eg.cpp

   1 //=======================================================================
   2 // Copyright 2001 Jeremy G. Siek, Andrew Lumsdaine, Lie-Quan Lee,
   3 //
   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>
   9 #include <iostream>
  10 #include <string>
  11 #include <boost/graph/push_relabel_max_flow.hpp>
  12 #include <boost/graph/adjacency_list.hpp>
  13 #include <boost/graph/read_dimacs.hpp>
  14
  15 // Use a DIMACS network flow file as stdin.
  16 // push-relabel-eg < max_flow.dat
  17 //
  18 // Sample output:
  19 //  c  The total flow:
  20 //  s 13
  21 //
  22 //  c flow values:
  23 //  f 0 6 3
  24 //  f 0 1 0
  25 //  f 0 2 10
  26 //  f 1 5 1
  27 //  f 1 0 0
  28 //  f 1 3 0
  29 //  f 2 4 4
  30 //  f 2 3 6
  31 //  f 2 0 0
  32 //  f 3 7 5
  33 //  f 3 2 0
  34 //  f 3 1 1
  35 //  f 4 5 4
  36 //  f 4 6 0
  37 //  f 5 4 0
  38 //  f 5 7 5
  39 //  f 6 7 3
  40 //  f 6 4 0
  41 //  f 7 6 0
  42 //  f 7 5 0
  43
  44
  45 int
  46 main()
  47 {
  48   using namespace boost;
  49   typedef adjacency_list_traits < vecS, vecS, directedS > Traits;
  50   typedef adjacency_list < vecS, vecS, directedS,
  51     property < vertex_name_t, std::string >,
  52     property < edge_capacity_t, long,
  53     property < edge_residual_capacity_t, long,
  54     property < edge_reverse_t, Traits::edge_descriptor > > > > Graph;
  55   Graph g;
  56
  57   property_map < Graph, edge_capacity_t >::type
  58     capacity = get(edge_capacity, g);
  59   property_map < Graph, edge_residual_capacity_t >::type
  60     residual_capacity = get(edge_residual_capacity, g);
  61   property_map < Graph, edge_reverse_t >::type rev = get(edge_reverse, g);
  62   Traits::vertex_descriptor s, t;
  63   read_dimacs_max_flow(g, capacity, rev, s, t);
  64
  65 #if defined(BOOST_MSVC) && BOOST_MSVC <= 1300
  66   property_map<Graph, vertex_index_t>::type indexmap = get(vertex_index, g);
  67   long flow = push_relabel_max_flow(g, s, t, capacity, residual_capacity, rev,
  68                                     indexmap);
  69 #else
  70   long flow = push_relabel_max_flow(g, s, t);
  71 #endif
  72
  73   std::cout << "c  The total flow:" << std::endl;
  74   std::cout << "s " << flow << std::endl << std::endl;
  75   std::cout << "c flow values:" << std::endl;
  76   graph_traits < Graph >::vertex_iterator u_iter, u_end;
  77   graph_traits < Graph >::out_edge_iterator ei, e_end;
  78   for (boost::tie(u_iter, u_end) = vertices(g); u_iter != u_end; ++u_iter)
  79     for (boost::tie(ei, e_end) = out_edges(*u_iter, g); ei != e_end; ++ei)
  80       if (capacity[*ei] > 0)
  81         std::cout << "f " << *u_iter << " " << target(*ei, g) << " "
  82           << (capacity[*ei] - residual_capacity[*ei]) << std::endl;
  83   return EXIT_SUCCESS;
  84 }