/* -*- 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 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);

    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> 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";

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

	  writeEdgeMap("lo_cap", lo).

	  writeEdgeMap("up_cap", up).

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

	  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.barrierMap(bar);

      if(!gen.checkBarrier()) 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";

}