1// Copyright (c) 2006, Stephan Diederich
2//
3// This code may be used under either of the following two licences:
4//
5// Permission is hereby granted, free of charge, to any person
6// obtaining a copy of this software and associated documentation
7// files (the "Software"), to deal in the Software without
8// restriction, including without limitation the rights to use,
9// copy, modify, merge, publish, distribute, sublicense, and/or
10// sell copies of the Software, and to permit persons to whom the
11// Software is furnished to do so, subject to the following
12// conditions:
13//
14// The above copyright notice and this permission notice shall be
15// included in all copies or substantial portions of the Software.
16//
17// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
19// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
21// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
22// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
23// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
24// OTHER DEALINGS IN THE SOFTWARE. OF SUCH DAMAGE.
25//
26// Or:
27//
28// Distributed under the Boost Software License, Version 1.0.
29// (See accompanying file LICENSE_1_0.txt or copy at
30// http://www.boost.org/LICENSE_1_0.txt)
31
32/*
33 Writes maximal flow problem in extended DIMACS format to an OutputIterator
34 Vertex indices are read from an IndexMap and shiftet by 1.
35 so their new range is [1..num_vertices(g)]
36*/
37
38/* ----------------------------------------------------------------- */
39
40#include <vector>
41#include <string>
42#include <ostream>
43
44namespace boost {
45
46template <class Graph, class CapacityMap, class IndexMap>
47void write_dimacs_max_flow(const Graph& g,
48 CapacityMap capacity,
49 IndexMap idx,
50 typename graph_traits<Graph>::vertex_descriptor src,
51 typename graph_traits<Graph>::vertex_descriptor sink,
52 std::ostream& out)
53{
54 typedef typename graph_traits<Graph>::edge_iterator edge_iterator;
55
56 out << "c DIMACS max-flow file generated from boost::write_dimacs_max_flow" << std::endl;
57 out << "p max " << num_vertices(g) << " " << num_edges(g) << std::endl; //print problem description "max" and number of verts and edges
58 out << "n " << get(idx, src) + 1 << " s" << std::endl;; //say which one is source
59 out << "n " << get(idx, sink) + 1 << " t" << std::endl; //say which one is sink
60
61 //output the edges
62 edge_iterator ei, e_end;
63 for(boost::tie(ei,e_end) = edges(g); ei!=e_end; ++ei){
64 out << "a " << idx[ source(*ei, g) ] + 1 << " " << idx[ target(*ei, g) ] + 1 << " " << get(capacity,*ei) << std::endl;
65 }
66}
67
68} // namespace boost
69

source code of boost/boost/graph/write_dimacs.hpp