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1   /*******************************************************************************
2    * SAT4J: a SATisfiability library for Java Copyright (C) 2004-2008 Daniel Le Berre
3    *
4    * All rights reserved. This program and the accompanying materials
5    * are made available under the terms of the Eclipse Public License v1.0
6    * which accompanies this distribution, and is available at
7    * http://www.eclipse.org/legal/epl-v10.html
8    *
9    * Alternatively, the contents of this file may be used under the terms of
10   * either the GNU Lesser General Public License Version 2.1 or later (the
11   * "LGPL"), in which case the provisions of the LGPL are applicable instead
12   * of those above. If you wish to allow use of your version of this file only
13   * under the terms of the LGPL, and not to allow others to use your version of
14   * this file under the terms of the EPL, indicate your decision by deleting
15   * the provisions above and replace them with the notice and other provisions
16   * required by the LGPL. If you do not delete the provisions above, a recipient
17   * may use your version of this file under the terms of the EPL or the LGPL.
18   * 
19   * Based on the pseudo boolean algorithms described in:
20   * A fast pseudo-Boolean constraint solver Chai, D.; Kuehlmann, A.
21   * Computer-Aided Design of Integrated Circuits and Systems, IEEE Transactions on
22   * Volume 24, Issue 3, March 2005 Page(s): 305 - 317
23   * 
24   * and 
25   * Heidi E. Dixon, 2004. Automating Pseudo-Boolean Inference within a DPLL 
26   * Framework. Ph.D. Dissertation, University of Oregon.
27   *******************************************************************************/
28  package org.sat4j.pb.constraints;
29  
30  import java.math.BigInteger;
31  
32  import org.sat4j.core.Vec;
33  import org.sat4j.core.VecInt;
34  import org.sat4j.minisat.constraints.card.MinWatchCard;
35  import org.sat4j.minisat.constraints.cnf.Clauses;
36  import org.sat4j.minisat.constraints.cnf.LearntBinaryClause;
37  import org.sat4j.minisat.constraints.cnf.LearntHTClause;
38  import org.sat4j.minisat.constraints.cnf.OriginalBinaryClause;
39  import org.sat4j.minisat.constraints.cnf.OriginalHTClause;
40  import org.sat4j.minisat.constraints.cnf.UnitClause;
41  import org.sat4j.minisat.core.Constr;
42  import org.sat4j.pb.constraints.pb.IDataStructurePB;
43  import org.sat4j.specs.ContradictionException;
44  import org.sat4j.specs.IVec;
45  import org.sat4j.specs.IVecInt;
46  
47  public class CompetResolutionPBMixedHTClauseCardConstrDataStructure extends
48  		PBMaxClauseCardConstrDataStructure {
49  
50  	private static final long serialVersionUID = 1L;
51  
52  	@Override
53  	public Constr createClause(IVecInt literals) throws ContradictionException {
54  		IVecInt v = Clauses.sanityCheck(literals, getVocabulary(), solver);
55  		if (v == null)
56  			return null;
57  		if (v.size() == 2) {
58  			return OriginalBinaryClause.brandNewClause(solver, getVocabulary(),
59  					v);
60  		}
61  		return OriginalHTClause.brandNewClause(solver, getVocabulary(), v);
62  	}
63  
64  	@Override
65  	protected Constr constructClause(IVecInt v) {
66  		if (v == null)
67  			return null;
68  		if (v.size() == 2) {
69  			return OriginalBinaryClause.brandNewClause(solver, getVocabulary(),
70  					v);
71  		}
72  		return OriginalHTClause.brandNewClause(solver, getVocabulary(), v);
73  	}
74  
75  	@Override
76  	protected Constr constructLearntClause(IVecInt resLits) {
77  		if (resLits.size() == 1) {
78  			return new UnitClause(resLits.last());
79  		}
80  		if (resLits.size() == 2) {
81  			return new LearntBinaryClause(resLits, getVocabulary());
82  		}
83  		return new LearntHTClause(resLits, getVocabulary());
84  	}
85  
86  	@Override
87  	protected Constr constructCard(IVecInt theLits, int degree)
88  			throws ContradictionException {
89  		return MinWatchCard.minWatchCardNew(solver, getVocabulary(), theLits,
90  				MinWatchCard.ATLEAST, degree);
91  	}
92  
93  	@Override
94  	protected Constr constructLearntCard(IDataStructurePB dspb) {
95  		IVecInt resLits = new VecInt();
96  		IVec<BigInteger> resCoefs = new Vec<BigInteger>();
97  		dspb.buildConstraintFromConflict(resLits, resCoefs);
98  		return new MinWatchCard(getVocabulary(), resLits, true, dspb
99  				.getDegree().intValue());
100 	}
101 
102 }