/* -*- C++ -*-

  *

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

  *

  * Copyright (C) 2003-2006

  * 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/graph_reader.h>

 #include <lemon/graph_writer.h>

 using namespace lemon;

 int main (int, char*[])

 {

     typedef ListGraph Graph;

     typedef Graph::Node Node;

     typedef Graph::NodeIt NodeIt;

     typedef Graph::Edge Edge;

     typedef Graph::EdgeIt EdgeIt;

     typedef Graph::EdgeMap<int> EdgeMap;

     typedef Graph::NodeMap<int> NodeMap;

     typedef Graph::NodeMap<double> DNodeMap;

     Graph g;

     EdgeMap lo(g);

     EdgeMap up(g);

     EdgeMap x(g);

     NodeMap delta(g);

     NodeMap nid(g);

     EdgeMap eid(g);

     DNodeMap cx(g);

     DNodeMap cy(g);

     GraphReader<Graph>("circulation-input.lgf", g).

       readEdgeMap("lo_cap", lo).

       readEdgeMap("up_cap", up).

       readNodeMap("delta", delta).

       readEdgeMap("label", eid).

       readNodeMap("label", nid).

       readNodeMap("coordinates_x", cx).

       readNodeMap("coordinates_y", cy).

       run();

     Circulation<Graph,int> gen(g,lo,up,delta,x);

     int ret=gen.run();

     if(ret==-1)

       {

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

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

 	GraphWriter<Graph>("circulation-output.lgf", g).

 	  writeEdgeMap("lo_cap", lo).

 	  writeEdgeMap("up_cap", up).

 	  writeEdgeMap("flow", x).

 	  writeNodeMap("delta", delta).

 	  writeEdgeMap("label", eid).

 	  writeNodeMap("label", nid).

 	  writeNodeMap("coordinates_x", cx).

 	  writeNodeMap("coordinates_y", cy).

 	  run();

       }

     else {

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

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

       gen.barrier(bar,ret);

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

       GraphWriter<Graph>("circulation-output.lgf", g).

 	writeEdgeMap("lo_cap", lo).

 	writeEdgeMap("up_cap", up).

 	writeNodeMap("barrier", bar).

 	writeNodeMap("delta", delta).

 	writeEdgeMap("label", eid).

 	writeNodeMap("label", nid).

 	writeNodeMap("coordinates_x", cx).

 	writeNodeMap("coordinates_y", cy).

 	run();

     }

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

 }