<HTML>
<!--
//  Copyright (c) 2006, Stephan Diederich
//  Copyright (c) 2010, Trustees of Indiana University
//
//  This code may be used under either of the following two licences:
//
//    Permission is hereby granted, free of charge, to any person
//    obtaining a copy of this software and associated documentation
//    files (the "Software"), to deal in the Software without
//    restriction, including without limitation the rights to use,
//    copy, modify, merge, publish, distribute, sublicense, and/or
//    sell copies of the Software, and to permit persons to whom the
//    Software is furnished to do so, subject to the following
//    conditions:
//
//    The above copyright notice and this permission notice shall be
//    included in all copies or substantial portions of the Software.
//
//    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
//    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
//    OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
//    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
//    HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
//    WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
//    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
//    OTHER DEALINGS IN THE SOFTWARE. OF SUCH DAMAGE.
//
//  Or:
//
//    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)
-->
<Head>
<Title>Boost Graph Library: read_dimacs_max_flow and read_dimacs_min_cut</Title>
<BODY BGCOLOR="#ffffff" LINK="#0000ee" TEXT="#000000" VLINK="#551a8b" 
        ALINK="#ff0000"> 
<IMG SRC="../../../boost.png" 
     ALT="C++ Boost" width="277" height="86"> 
<BR Clear>

<H1><A NAME="sec:read_dimacs_max_flow">
<TT>read_dimacs_max_flow</TT>
</H1>


<pre>
//reads a graph with attached edge_capacity properties from an std::istream
template &lt;class Graph, class CapacityMap, class ReverseEdgeMap&gt;
int read_dimacs_max_flow(Graph&amp; g,
                         CapacityMap capacity, 
                         ReverseEdgeMap reverse_edge,
                         typename graph_traits<Graph>::vertex_descriptor&amp; src,
                         typename graph_traits<Graph>::vertex_descriptor&amp; sink,
                         std::istream&amp; in=std::cin)

//reads a graph with attached edge_capacity properties from an std::istream
template &lt;class Graph, class CapacityMap, class ReverseEdgeMap&gt;
int read_dimacs_min_cut(Graph&amp; g,
                        CapacityMap capacity, 
                        ReverseEdgeMap reverse_edge,
                        std::istream&amp; in=std::cin)

</pre>

<p>
These functions read a BGL graph object from a max-flow or min-cut problem description in extended dimacs format. (see <a href="http://www.avglab.com/andrew/CATS/maxflow_formats.htm"><TT>Goldberg's site</TT></a> for more information). For each edge found in the 
file an additional reverse_edge is added and set in the reverse_edge map.  For
max-flow problems, source and sink vertex descriptors are set according to the
dimacs file.
 
<H3>Where Defined</H3>

<P>
<a href="../../../boost/graph/read_dimacs.hpp"><TT>boost/graph/read_dimacs.hpp</TT></a>

<h3>Parameters</h3>
 IN: <tt>Graph&amp; g</tt>
<blockquote>
  A directed or undirected graph. The graph's type must be a model of <a href="./IncidenceGraph.html">IncidenceGraph</a>. 
</blockquote>  

 OUT: <tt>CapacityMap capacity</tt>
<blockquote>
 A property map that models <a href="../../property_map/doc/LvaluePropertyMap.html">mutable Lvalue Property Map</a> whose key type is the edge descriptor of the graph. <br>
</blockquote>  

 OUT: <tt>ReverseEdgeMap reverse_edge</tt>
<blockquote>
 A property map that models <a href="../../property_map/doc/LvaluePropertyMap.html">mutable Lvalue Property Map</a> whose key and value type is the edge descriptor of the graph. This map stores the corresponding reverse edge for each each in Graph g.<br>
</blockquote>  
  
 OUT: <tt>vertex_descriptor&amp; src</tt>
<blockquote>
 A graph vertex that will be set to the source of a max-flow problem.
</blockquote>  
  
 OUT: <tt>vertex_descriptor&amp; sink</tt>
<blockquote>
 A graph vertex that will be set to the sink of a max-flow problem.
</blockquote>  
  
 IN: <tt>std::istream&amp; in</tt>
<blockquote>
  A standard <tt>std::istream</tt> object. <br>
  <b>Default</b>: <tt>std::cin (for backward compatibility)</tt>
</blockquote>  

<H3>
Example 
</H3>
A short <a href="../example/read_write_dimacs-eg.cpp">example</a> which uses read_dimacs and write_dimacs is located in the examples directory.

<h3>See Also</h3>

<a href="./write_dimacs.html"><tt>write_dimacs</tt></a>
</BODY>
</HTML>