/* -*- 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.

 *

 */

#include "test_tools.h"

#ifdef HAVE_CONFIG_H

#include <lemon/config.h>

#endif

#ifdef HAVE_CPLEX

#include <lemon/mip_cplex.h>

#endif

#ifdef HAVE_GLPK

#include <lemon/mip_glpk.h>

#endif

using namespace lemon;

void solveAndCheck(MipSolverBase& lp, MipSolverBase::SolutionStatus stat, 

		   double exp_opt) {

  using std::string;

  lp.solve();

  //int decimal,sign;

  std::ostringstream buf;

  buf << "Primalstatus should be: " << int(stat)<<" and it is "<<int(lp.mipStatus());

  //  itoa(stat,buf1, 10);

  check(lp.mipStatus()==stat, buf.str());

  if (stat ==  MipSolverBase::OPTIMAL) {

    std::ostringstream sbuf;

    buf << "Wrong optimal value: the right optimum is " << exp_opt; 

    check(std::abs(lp.primalValue()-exp_opt) < 1e-3, sbuf.str());

    //+ecvt(exp_opt,2)

  }

}

void aTest(MipSolverBase& mip)

{

 //The following example is very simple

  typedef MipSolverBase::Row Row;

  typedef MipSolverBase::Col Col;

  Col x1 = mip.addCol();

  Col x2 = mip.addCol();

  //Objective function

  mip.obj(x1);

  mip.max();

  //Unconstrained optimization

  mip.solve();

  //Check it out!

  //Constraints

  mip.addRow(2*x1+x2 <=2);  

  mip.addRow(x1-2*x2 <=0);

  //Nonnegativity of the variable x1

  mip.colLowerBound(x1, 0);

  //Maximization of x1

  //over the triangle with vertices (0,0),(4/5,2/5),(0,2)

  double expected_opt=4.0/5.0;

  solveAndCheck(mip, MipSolverBase::OPTIMAL, expected_opt);

  //Restrict x2 to integer

  mip.colType(x2,MipSolverBase::INT);  

  expected_opt=1.0/2.0;

  solveAndCheck(mip, MipSolverBase::OPTIMAL, expected_opt);

  //Restrict both to integer

  mip.colType(x1,MipSolverBase::INT);  

  expected_opt=0;

  solveAndCheck(mip, MipSolverBase::OPTIMAL, expected_opt);

}

int main() 

{

#ifdef HAVE_GLPK

  MipGlpk mip1;

  aTest(mip1);

#endif

#ifdef HAVE_CPLEX

  MipCplex mip2;

  aTest(mip2);

#endif

  return 0;

}