/* -*- 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 Mixed integer program solver demo

 ///

 /// This example shows how can we solve an integer program with lemon

 /// \c Mip interface and with default solver.

 ///

 /// \include mip_demo.cc

 #include <lemon/lp.h>

 using namespace lemon;

 int main(){

    Mip ilp;

   typedef Mip::Row Row;

   typedef Mip::Col Col;

   ilp.max();

   Col x1 = ilp.addCol();

   Col x2 = ilp.addCol();

   Col x3 = ilp.addCol();

   ilp.integer(x1,true);

   ilp.integer(x2,true);

   ilp.integer(x3,true);

   ilp.addRow(x1+x2+x3 <=100);  

   ilp.addRow(10*x1+4*x2+5*x3<=600);  

   ilp.addRow(2*x1+2*x2+6*x3<=300); 

   ilp.colLowerBound(x1, 0);

   ilp.colLowerBound(x2, 0);

   ilp.colLowerBound(x3, 0);

   //Objective function

   ilp.obj(10*x1+6*x2+4*x3);

   //Call the routine of the underlying LP solver

   ilp.solve();

   //Print results

   if (ilp.primalStatus()==LpSolverBase::OPTIMAL){

     std::cout<<"Optimal solution found!"<<std::endl;

     printf("optimum value = %g; x1 = %g; x2 = %g; x3 = %g\n", 

            ilp.primalValue(), 

            ilp.primal(x1), ilp.primal(x2), ilp.primal(x3));

   }

   else{

     std::cout<<"Optimal solution not found!"<<std::endl;

   }

 }