/* -*- 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;

 }