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* Copyright (c) 1999-2014, Ecole des Mines de Nantes
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*
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* documentation and/or other materials provided with the distribution.
* * Neither the name of the Ecole des Mines de Nantes nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
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package samples.nqueen;
import solver.constraints.Constraint;
import solver.constraints.IntConstraintFactory;
import solver.search.strategy.IntStrategyFactory;
import solver.variables.IntVar;
import solver.variables.VariableFactory;
import java.util.HashSet;
/**
* <br/>
*
* @author Charles Prud'homme
* @since 31/03/11
*/
public class NQueenBinary extends AbstractNQueen {
HashSet<Constraint> set;
@Override
public void buildModel() {
set = new HashSet<Constraint>();
vars = new IntVar[n];
for (int i = 0; i < vars.length; i++) {
vars[i] = VariableFactory.enumerated("Q_" + i, 1, n, solver);
}
for (int i = 0; i < n - 1; i++) {
for (int j = i + 1; j < n; j++) {
int k = j - i;
Constraint neq = IntConstraintFactory.arithm(vars[i], "!=", vars[j]);
solver.post(neq);
set.add(neq);
solver.post(IntConstraintFactory.arithm(vars[i], "!=", vars[j], "+", -k));
solver.post(IntConstraintFactory.arithm(vars[i], "!=", vars[j], "+", k));
}
}
}
@Override
public void configureSearch() {
solver.set(IntStrategyFactory.minDom_LB(vars));
// SearchMonitorFactory.log(solver, true, false);
}
public static void main(String[] args) {
new NQueenBinary().execute(args);
}
}