/*
 * $Revision: 2523 $
 *
 * last checkin:
 *   $Author: gutwenger $
 *   $Date: 2012-07-02 20:59:27 +0200 (Mon, 02 Jul 2012) $
 ***************************************************************/

/** \file
 * \brief Declaration of min-cost-flow algorithm (class
 *        MinCostFlowReinelt)
 *
 * \author Carsten Gutwenger and Gerhard Reinelt
 *
 * \par License:
 * This file is part of the Open Graph Drawing Framework (OGDF).
 *
 * \par
 * Copyright (C)<br>
 * See README.txt in the root directory of the OGDF installation for details.
 *
 * \par
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * Version 2 or 3 as published by the Free Software Foundation;
 * see the file LICENSE.txt included in the packaging of this file
 * for details.
 *
 * \par
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * \par
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 * \see  http://www.gnu.org/copyleft/gpl.html
 ***************************************************************/


#ifdef _MSC_VER
#pragma once
#endif

#ifndef OGDF_MIN_COST_FLOW_REINELT_H
#define OGDF_MIN_COST_FLOW_REINELT_H


#include <ogdf/module/MinCostFlowModule.h>
#include <limits.h>


namespace ogdf {


class OGDF_EXPORT MinCostFlowReinelt : public MinCostFlowModule
{
public:
	MinCostFlowReinelt() { }

	// computes min-cost flow
	// Precond.: graph must be connected, lowerBound[e] <= upperBound[e]
	//   for all edges e, sum over all supply[v] equals 0
	// returns true iff a feasible min-cost flow exists
	bool call(
		const Graph &G,                   // directed graph
		const EdgeArray<int> &lowerBound, // lower bound for flow
		const EdgeArray<int> &upperBound, // upper bound for flow
		const EdgeArray<int> &cost,       // cost of an edge
		const NodeArray<int> &supply,     // supply (if neg. demand) of a node
		EdgeArray<int> &flow);            // computed flow

	bool call(
		const Graph &G,                   // directed graph
		const EdgeArray<int> &lowerBound, // lower bound for flow
		const EdgeArray<int> &upperBound, // upper bound for flow
		const EdgeArray<int> &cost,       // cost of an edge
		const NodeArray<int> &supply,     // supply (if neg. demand) of a node
		EdgeArray<int> &flow,			  // computed flow
		NodeArray<int> &dual);            // computed dual variables

	int infinity() const { return INT_MAX; }

private:

	struct arctype;

	struct nodetype {
		nodetype *father;     /* ->father in basis tree */
		nodetype *successor;  /* ->successor in preorder */
		arctype *arc_id;      /* ->arc (node,father) */
		bool orientation;     /* false<=>basic arc=(father->node)*/
		int dual;             /* value of dual variable */
		int flow;             /* flow in basic arc (node,father) */
		int name;             /* identification of node = node-nr*/
		nodetype *last;       /* last node in subtree */
		int nr_of_nodes;      /* number of nodes in subtree */
	};

	struct arctype {
		arctype *next_arc;    /* -> next arc in list */
		nodetype *tail;       /* -> tail of arc */
		nodetype *head;       /* -> head of arc */
		int cost;             /* cost of unit flow */
		int upper_bound;      /* capacity of arc */
		int arcnum;           /* number of arc in input */

		OGDF_NEW_DELETE
	};


	int mcf(
		int mcfNrNodes,
		int mcfNrArcs,
		Array<int> &mcfSupply,
		Array<int> &mcfTail,
		Array<int> &mcfHead,
		Array<int> &mcfLb,
		Array<int> &mcfUb,
		Array<int> &mcfCost,
		Array<int> &mcfFlow,
		Array<int> &mcfDual,
		int *mcfObj
	);

	void start(Array<int> &supply);

	void beacircle(arctype **eplus, arctype **pre, bool *from_ub);
	void beadouble(arctype **eplus, arctype **pre, bool *from_ub);


	Array<nodetype> nodes;     /* node space */
	Array<arctype> arcs;       /* arc space */
	//Array<nodetype *> p;    /*used for starting procedure*/

	nodetype *root;         /*->root of basis tree*/
	nodetype rootStruct;

	arctype *last_n1;       /*->start for search for entering arc in N' */
	arctype *last_n2;       /*->start for search for entering arc in N''*/
	arctype *start_arc;     /* -> initial arc list*/
	arctype *start_b;       /* -> first basic arc*/
	arctype *start_n1;      /* -> first nonbasic arc in n'*/
	arctype *start_n2;      /* -> first nonbasic arc in n''*/
	arctype *startsearch;   /* ->start of search for basis entering arc */
	arctype *searchend;     /* ->end of search for entering arc in bea */
	arctype *searchend_n1;  /*->end of search for entering arc in N' */
	arctype *searchend_n2;  /*->end of search for entering arc in N''*/

	//int artvalue;          /*cost and upper_bound of artificial arc */
	int m_maxCost;         // maximum of the cost of all input arcs

	int nn;                /*number of original nodes*/
	int mm;                /*number of original arcs*/

};


} // end namespace ogdf


#endif
