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.pb.constraints.pb.PBConstr;
36 import org.sat4j.pb.constraints.pb.Pseudos;
37 import org.sat4j.specs.ContradictionException;
38 import org.sat4j.specs.IVec;
39 import org.sat4j.specs.IVecInt;
40
41 /**
42 *
43 * @author anne
44 */
45 public class CompetPBMaxClauseCardConstrDataStructure
46 extends PBMaxClauseCardConstrDataStructure{
47
48 /**
49 *
50 */
51 private static final long serialVersionUID = 1L;
52
53 /*
54 * (non-Javadoc)
55 *
56 * @see org.sat4j.minisat.constraints.AbstractPBDataStructureFactory#constraintFactory(org.sat4j.specs.VecInt,
57 * org.sat4j.specs.VecInt, boolean, int)
58 */
59 @Override
60 protected PBConstr constraintFactory(IVecInt literals,
61 IVec<BigInteger> coefs, boolean moreThan, BigInteger degree)
62 throws ContradictionException {
63 int[] theLits = new int[literals.size()];
64 literals.copyTo(theLits);
65 BigInteger[] normCoefs = new BigInteger[coefs.size()];
66 coefs.copyTo(normCoefs);
67
68 BigInteger bigDegree = Pseudos.niceParametersForCompetition(theLits, normCoefs,
69 moreThan, degree);
70 if (bigDegree == null)
71 return null;
72 if (bigDegree.equals(BigInteger.ONE)) {
73 IVecInt v = Clauses.sanityCheck(new VecInt(theLits), getVocabulary(),
74 solver);
75 if (v == null)
76 return null;
77 return constructClause(v);
78 }
79 if (coefficientsEqualToOne(new Vec<BigInteger>(normCoefs))) {
80 assert bigDegree.compareTo(MAX_INT_VALUE) < 0;
81 return constructCard(new VecInt(theLits), bigDegree.intValue());
82 }
83 //return constructPB(mpb);
84 return constructPB(theLits,normCoefs,bigDegree);
85 }
86
87 }