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// $Id: simpleBAB.cpp 1898 2013-04-09 18:06:04Z stefan $
// Copyright (C) 2009, 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>
#include "CoinPragma.hpp"
#include "OsiClpSolverInterface.hpp"
#include "CoinPackedVector.hpp"
//#define USE_CBC
#ifdef USE_CBC
#include "CbcModel.hpp"
#endif
int main (int argc, const char *argv[])
{
OsiClpSolverInterface model;
int start[] = { 0, 1, 2};
int index[] = { 0, 0};
double values[] = {1.0, 2.0};
double collb[] = {0.0, 0.0};
double colub[] = {10.0, 10.0};
double obj[] = { 1.0, 1.0};
double rowlb[] = { 0.0};
double rowub[]= { 3.9};
// obj: Max x0 + x1
// st. x0 + 2 x1 <= 3.9
// 0 <= x0 <= 10 and integer
// 0 <= x1 <= 10
model.loadProblem(2, 1, start, index, values, collb, colub, obj, rowlb, rowub);
model.setInteger(0);
model.setObjSense(-1.0);
//bool optimal;
#ifndef USE_CBC
// Save bounds - that and dual limit should be all that is needed
// For this simple example we could just re-use collb and colub
double saveLower[2];
double saveUpper[2];
int numberColumns = model.getNumCols();
CoinCopyN(model.getColLower(),numberColumns,saveLower);
CoinCopyN(model.getColUpper(),numberColumns,saveUpper);
double objLimit;
model.getDblParam(OsiDualObjectiveLimit,objLimit);
model.branchAndBound();
//optimal = model.isProvenOptimal();
const double *val = model.getColSolution(); // x0 = 3, x1 = 0.45
printf("Solution %g %g\n",val[0],val[1]);
// Restore bounds and dual limit
model.setColLower(saveLower);
model.setColUpper(saveUpper);
model.setDblParam(OsiDualObjectiveLimit,objLimit);
#else
{
CbcModel model2(model);
model2.branchAndBound();
//optimal = model2.isProvenOptimal();
const double *val = model2.getColSolution(); // x0 = 3, x1 = 0.45
printf("Solution %g %g\n",val[0],val[1]);
}
#endif
const int rowCols[] = {0};
const double rowElements = { 1.0};
// add x0 <= 2, and solve once again.
CoinPackedVector v(1, rowCols, rowElements);
model.addRow(v, 0.0, 2.0);
#ifndef USE_CBC
model.branchAndBound();
//optimal = model.isProvenOptimal(); // should be x0 = 2, x1 = 0.95
// Address of solution will be same as only adding rows - but be safe
val = model.getColSolution();
printf("Solution %g %g\n",val[0],val[1]);
#else
{
CbcModel model2(model);
model2.branchAndBound();
//optimal = model2.isProvenOptimal(); // should be x0 = 2, x1 = 0.95
const double *val = model2.getColSolution();
printf("Solution %g %g\n",val[0],val[1]);
}
#endif
return 0;
}
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