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1   /*
2    * SAT4J: a SATisfiability library for Java Copyright (C) 2004-2006 Daniel Le Berre
3    * 
4    * Based on the original minisat specification from:
5    * 
6    * An extensible SAT solver. Niklas E?n and Niklas S?rensson. Proceedings of the
7    * Sixth International Conference on Theory and Applications of Satisfiability
8    * Testing, LNCS 2919, pp 502-518, 2003.
9    * 
10   * This library is free software; you can redistribute it and/or modify it under
11   * the terms of the GNU Lesser General Public License as published by the Free
12   * Software Foundation; either version 2.1 of the License, or (at your option)
13   * any later version.
14   * 
15   * This library is distributed in the hope that it will be useful, but WITHOUT
16   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
17   * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
18   * details.
19   * 
20   * You should have received a copy of the GNU Lesser General Public License
21   * along with this library; if not, write to the Free Software Foundation, Inc.,
22   * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23   * 
24   */
25  package org.sat4j.minisat.constraints.pb;
26  
27  import java.math.BigInteger;
28  
29  import org.sat4j.minisat.core.AssertingClauseGenerator;
30  import org.sat4j.minisat.core.DataStructureFactory;
31  import org.sat4j.minisat.core.ILits;
32  import org.sat4j.minisat.core.IOrder;
33  import org.sat4j.minisat.core.LearningStrategy;
34  import org.sat4j.specs.ContradictionException;
35  import org.sat4j.specs.IConstr;
36  import org.sat4j.specs.IVec;
37  import org.sat4j.specs.IVecInt;
38  
39  public class PBSolverWithImpliedClause extends PBSolver<ILits> {
40  
41      public PBSolverWithImpliedClause(AssertingClauseGenerator acg,
42              LearningStrategy<ILits> learner, DataStructureFactory<ILits> dsf, IOrder<ILits> order) {
43          super(acg, learner, dsf, order);
44      }
45  
46      /**
47       * 
48       */
49      private static final long serialVersionUID = 1L;
50  
51      @Override
52      public IConstr addPseudoBoolean(IVecInt literals, IVec<BigInteger> coeffs,
53              boolean moreThan, BigInteger degree) throws ContradictionException {
54          IVecInt vlits = dimacs2internal(literals);
55          assert vlits.size() == literals.size();
56          assert literals.size() == coeffs.size();
57          PBConstr result = (PBConstr) dsfactory.createPseudoBooleanConstraint(
58                  vlits, coeffs, moreThan, degree);
59          if (result != null) {
60              IVecInt clits = result.computeAnImpliedClause();
61              if (clits != null) {
62                  addConstr(dsfactory.createClause(clits));
63              }
64          }
65          return addConstr(result);
66      }
67  
68      @Override
69      public String toString(String prefix) {
70          return super.toString(prefix) + "\n" + prefix
71                  + "Add implied clauses in preprocessing";
72      }
73  }