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
44 namespace boost
45 {
46
47 template < class Graph, class CapacityMap, class IndexMap >
write_dimacs_max_flow(const Graph & g,CapacityMap capacity,IndexMap idx,typename graph_traits<Graph>::vertex_descriptor src,typename graph_traits<Graph>::vertex_descriptor sink,std::ostream & out)48 void write_dimacs_max_flow(const Graph& g, CapacityMap capacity, IndexMap idx,
49 typename graph_traits< Graph >::vertex_descriptor src,
50 typename graph_traits< Graph >::vertex_descriptor sink, std::ostream& out)
51 {
52 typedef typename graph_traits< Graph >::edge_iterator edge_iterator;
53
54 out << "c DIMACS max-flow file generated from boost::write_dimacs_max_flow"
55 << std::endl;
56 out << "p max " << num_vertices(g) << " " << num_edges(g)
57 << std::endl; // print problem description "max" and number of verts and
58 // edges
59 out << "n " << get(idx, src) + 1 << " s" << std::endl;
60 ; // say which one is source
61 out << "n " << get(idx, sink) + 1 << " t"
62 << std::endl; // say which one is sink
63
64 // output the edges
65 edge_iterator ei, e_end;
66 for (boost::tie(ei, e_end) = edges(g); ei != e_end; ++ei)
67 {
68 out << "a " << idx[source(*ei, g)] + 1 << " " << idx[target(*ei, g)] + 1
69 << " " << get(capacity, *ei) << std::endl;
70 }
71 }
72
73 } // namespace boost
74