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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.cnf.Clauses;
35  import org.sat4j.minisat.core.Constr;
36  import org.sat4j.pb.constraints.pb.IDataStructurePB;
37  import org.sat4j.pb.constraints.pb.LearntBinaryClausePB;
38  import org.sat4j.pb.constraints.pb.LearntHTClausePB;
39  import org.sat4j.pb.constraints.pb.MinWatchCardPB;
40  import org.sat4j.pb.constraints.pb.OriginalBinaryClausePB;
41  import org.sat4j.pb.constraints.pb.OriginalHTClausePB;
42  import org.sat4j.pb.constraints.pb.PuebloMinWatchPb;
43  import org.sat4j.pb.constraints.pb.UnitClausePB;
44  import org.sat4j.specs.ContradictionException;
45  import org.sat4j.specs.IVec;
46  import org.sat4j.specs.IVecInt;
47  
48  public class PuebloPBMinClauseCardConstrDataStructure extends
49  		AbstractPBClauseCardConstrDataStructure {
50  
51  	/**
52       * 
53       */
54  	private static final long serialVersionUID = 1L;
55  
56  	@Override
57  	public Constr createClause(IVecInt literals) throws ContradictionException {
58  		IVecInt v = Clauses.sanityCheck(literals, getVocabulary(), solver);
59  		if (v == null)
60  			return null;
61  		if (v.size() == 2) {
62  			return OriginalBinaryClausePB.brandNewClause(solver,
63  					getVocabulary(), v);
64  		}
65  		return OriginalHTClausePB.brandNewClause(solver, getVocabulary(), v);
66  	}
67  
68  	@Override
69  	protected Constr constructClause(IVecInt v) {
70  		if (v.size() == 2) {
71  			return OriginalBinaryClausePB.brandNewClause(solver,
72  					getVocabulary(), v);
73  		}
74  		return OriginalHTClausePB.brandNewClause(solver, getVocabulary(), v);
75  	}
76  
77  	@Override
78  	protected Constr constructCard(IVecInt theLits, int degree)
79  			throws ContradictionException {
80  		return MinWatchCardPB.normalizedMinWatchCardPBNew(solver,
81  				getVocabulary(), theLits, degree);
82  	}
83  
84  	@Override
85  	protected Constr constructPB(int[] theLits, BigInteger[] coefs,
86  			BigInteger degree) throws ContradictionException {
87  		return PuebloMinWatchPb.normalizedMinWatchPbNew(solver,
88  				getVocabulary(), theLits, coefs, degree);
89  	}
90  
91  	@Override
92  	protected Constr constructLearntClause(IVecInt literals) {
93  		if (literals.size() == 1) {
94  			return new UnitClausePB(literals.last(), getVocabulary());
95  		}
96  		if (literals.size() == 2) {
97  			return new LearntBinaryClausePB(literals, getVocabulary());
98  		}
99  		return new LearntHTClausePB(literals, getVocabulary());
100 	}
101 
102 	@Override
103 	protected Constr constructLearntCard(IDataStructurePB dspb) {
104 		IVecInt resLits = new VecInt();
105 		IVec<BigInteger> resCoefs = new Vec<BigInteger>();
106 		dspb.buildConstraintFromConflict(resLits, resCoefs);
107 		return new MinWatchCardPB(getVocabulary(), resLits, true, dspb
108 				.getDegree().intValue());
109 	}
110 
111 	@Override
112 	protected Constr constructLearntPB(IDataStructurePB dspb) {
113 		return PuebloMinWatchPb.normalizedWatchPbNew(getVocabulary(), dspb);
114 	}
115 
116 }