/* -*- mode: C++; indent-tabs-mode: nil; -*-

  *

  * 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 the usage of LEMON's General Flow algorithm

 ///

 /// This demo program reads a general network circulation problem from the

 /// file 'circulation-input.lgf', runs the preflow based algorithm for

 /// finding a feasible solution and writes the output

 /// to 'circulation-input.lgf'

 ///

 /// \include circulation_demo.cc

 #include <iostream>

 #include <lemon/list_graph.h>

 #include <lemon/circulation.h>

 #include <lemon/lgf_reader.h>

 #include <lemon/lgf_writer.h>

 using namespace lemon;

 int main (int, char*[])

 {

     typedef ListDigraph Digraph;

     typedef Digraph::Node Node;

     typedef Digraph::NodeIt NodeIt;

     typedef Digraph::Arc Arc;

     typedef Digraph::ArcIt ArcIt;

     typedef Digraph::ArcMap<int> ArcMap;

     typedef Digraph::NodeMap<int> NodeMap;

     typedef Digraph::NodeMap<double> DNodeMap;

     Digraph g;

     ArcMap lo(g);

     ArcMap up(g);

     NodeMap delta(g);

     NodeMap nid(g);

     ArcMap eid(g);

     DNodeMap cx(g);

     DNodeMap cy(g);

     DigraphReader<Digraph>(g,"circulation-input.lgf").

       arcMap("lo_cap", lo).

       arcMap("up_cap", up).

       nodeMap("delta", delta).

       arcMap("label", eid).

       nodeMap("label", nid).

       nodeMap("coordinates_x", cx).

       nodeMap("coordinates_y", cy).

       run();

     Circulation<Digraph> gen(g,lo,up,delta);

     bool ret=gen.run();

     if(ret)

       {

         std::cout << "\nA feasible flow has been found.\n";

         if(!gen.checkFlow()) std::cerr << "Oops!!!\n";

         DigraphWriter<Digraph>(g, "circulation-output.lgf").

           arcMap("lo_cap", lo).

           arcMap("up_cap", up).

           arcMap("flow", gen.flowMap()).

           nodeMap("delta", delta).

           arcMap("label", eid).

           nodeMap("label", nid).

           nodeMap("coordinates_x", cx).

           nodeMap("coordinates_y", cy).

           run();

       }

     else {

       std::cout << "\nThere is no such a flow\n";

       Digraph::NodeMap<int> bar(g);

       gen.barrierMap(bar);

       if(!gen.checkBarrier()) std::cerr << "Dual Oops!!!\n";

       DigraphWriter<Digraph>(g, "circulation-output.lgf").

         arcMap("lo_cap", lo).

         arcMap("up_cap", up).

         nodeMap("barrier", bar).

         nodeMap("delta", delta).

         arcMap("label", eid).

         nodeMap("label", nid).

         nodeMap("coordinates_x", cx).

         nodeMap("coordinates_y", cy).

         run();

     }

   std::cout << "The output is written to file 'circulation-output.lgf'\n\n";

 }