driver2.cpp

// Copyright (C) 2005, International Business Machines
// Corporation and others.  All Rights Reserved.
// This code is licensed under the terms of the Eclipse Public License (EPL).

#include <cassert>
#include <iomanip>

// For Branch and bound
//#include "CbcStrategy.hpp"
#include "CoinPragma.hpp"
#include "OsiCbcSolverInterface.hpp"

#include "CoinTime.hpp"

//#############################################################################

/************************************************************************

This main program reads in an integer model from an mps file.
It then uses default strategy - just cuts at root node

************************************************************************/

int main(int argc, const char *argv[])
{

  // This would just do cuts at root
  // OsiCbcSolverInterface solver1;
  // This does cuts in tree and uses Clp
  CbcStrategyDefault strategy(false);
  OsiCbcSolverInterface solver1(NULL, &strategy);
  // Read in model using argv[1]
  // and assert that it is a clean model
  std::string mpsFileName;
#if defined(SAMPLEDIR)
  mpsFileName = SAMPLEDIR "/p0033.mps";
#else
  if (argc < 2) {
    fprintf(stderr, "Do not know where to find sample MPS files.\n");
    exit(1);
  }
#endif
  if (argc >= 2)
    mpsFileName = argv[1];
  int numMpsReadErrors = solver1.readMps(mpsFileName.c_str(), "");
  if (numMpsReadErrors != 0) {
    printf("%d errors reading MPS file\n", numMpsReadErrors);
    return numMpsReadErrors;
  }
  double time1 = CoinCpuTime();
  // Do complete search

  solver1.branchAndBound();

  std::cout << mpsFileName << " took " << CoinCpuTime() - time1 << " seconds, "
            << solver1.getNodeCount() << " nodes with objective "
            << solver1.getObjValue()
            << (!solver1.status() ? " Finished" : " Not finished")
            << std::endl;

  // Print solution if finished - we can't get names from Osi!

  if (solver1.getObjValue() * solver1.getObjSense() < 1.0e50) {
    int numberColumns = solver1.getNumCols();

    const double *solution = solver1.getColSolution();

    int iColumn;
    std::cout << std::setiosflags(std::ios::fixed | std::ios::showpoint) << std::setw(14);

    std::cout << "--------------------------------------" << std::endl;
    for (iColumn = 0; iColumn < numberColumns; iColumn++) {
      double value = solution[iColumn];
      if (fabs(value) > 1.0e-7 && solver1.isInteger(iColumn))
        std::cout << std::setw(6) << iColumn << " " << value << std::endl;
    }
    std::cout << "--------------------------------------" << std::endl;

    std::cout << std::resetiosflags(std::ios::fixed | std::ios::showpoint | std::ios::scientific);
  }
  return 0;
}