/* -*- C++ -*-

  *

  * This file is a part of LEMON, a generic C++ optimization library

  *

  * Copyright (C) 2003-2008

  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

  * (Egervary Research Group on Combinatorial Optimization, EGRES).

  *

  * Permission to use, modify and distribute this software is granted

  * provided that this copyright notice appears in all copies. For

  * precise terms see the accompanying LICENSE file.

  *

  * This software is provided "AS IS" with no warranty of any kind,

  * express or implied, and with no claim as to its suitability for any

  * purpose.

  *

  */

 ///\ingroup demos

 ///\file

 ///\brief Demonstrating graph input and output

 ///

 /// This program gives an example of how to load a directed graph from

 /// an \ref lgf-format "LGF" file with the \ref lemon::DigraphReader

 /// "DigraphReader" class.

 ///

 /// The \c "digraph.lgf" file:

 /// \include digraph.lgf

 ///

 /// And the program which reads it:

 /// \include lgf_demo.cc

 #include <iostream>

 #include <lemon/smart_graph.h>

 #include <lemon/lgf_reader.h>

 #include <lemon/lgf_writer.h>

 #include <lemon/random.h>

 using namespace lemon;

 int main() {

   SmartDigraph g;

   SmartDigraph::ArcMap<int> cap(g);

   SmartDigraph::Node s, t;

   digraphReader("digraph.lgf", g). // read the directeg graph into g

     arcMap("capacity", cap).       // read the 'capacity' arc map into cap

     node("source", s).             // read 'source' node to s

     node("target", t).             // read 'target' node to t

     run();

   std::cout << "Digraph read from 'digraph.lgf'" << std::endl;

   std::cout << "Number of nodes: " << countNodes(g) << std::endl;

   std::cout << "Number of arcs: " << countArcs(g) << std::endl;

   std::cout << "We can write it to the standard output:" << std::endl;

   digraphWriter(std::cout, g).     // write g to the standard output

     arcMap("capacity", cap).       // write cap into 'capacity'

     node("source", s).             // write s to 'source'

     node("target", t).             // write t to 'target'

     run();

   return 0;

 }