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 original MiniSat specification from:
20 *
21 * An extensible SAT solver. Niklas Een and Niklas Sorensson. Proceedings of the
22 * Sixth International Conference on Theory and Applications of Satisfiability
23 * Testing, LNCS 2919, pp 502-518, 2003.
24 *
25 * See www.minisat.se for the original solver in C++.
26 *
27 *******************************************************************************/
28 package org.sat4j.minisat.constraints;
29
30 import org.sat4j.minisat.constraints.cnf.Clauses;
31 import org.sat4j.minisat.constraints.cnf.LearntBinaryClause;
32 import org.sat4j.minisat.constraints.cnf.LearntHTClause;
33 import org.sat4j.minisat.constraints.cnf.Lits2;
34 import org.sat4j.minisat.constraints.cnf.OriginalHTClause;
35 import org.sat4j.minisat.constraints.cnf.UnitClause;
36 import org.sat4j.minisat.core.Constr;
37 import org.sat4j.minisat.core.ILits2;
38 import org.sat4j.specs.ContradictionException;
39 import org.sat4j.specs.IVecInt;
40
41 /**
42 * @author leberre To change the template for this generated type comment go to
43 * Window>Preferences>Java>Code Generation>Code and Comments
44 */
45 public class MixedDataStructureWithBinary extends AbstractDataStructureFactory<ILits2> {
46
47 private static final long serialVersionUID = 1L;
48
49 @Override
50 public ILits2 createLits() {
51 return new Lits2();
52 }
53
54 /*
55 * (non-Javadoc)
56 *
57 * @see org.sat4j.minisat.DataStructureFactory#createClause(org.sat4j.datatype.VecInt)
58 */
59 public Constr createClause(IVecInt literals) throws ContradictionException {
60 IVecInt v = Clauses.sanityCheck(literals, lits, solver);
61 if (v == null)
62 return null;
63 if (v.size() == 2) {
64 lits.binaryClauses(v.get(0), v.get(1));
65 return null;
66 }
67 return OriginalHTClause.brandNewClause(solver, lits, v);
68 }
69
70 /*
71 * (non-Javadoc)
72 *
73 * @see org.sat4j.minisat.DataStructureFactory#learnContraint(org.sat4j.minisat.Constr)
74 */
75 @Override
76 public void learnConstraint(Constr constr) {
77 if (constr.size() == 2) {
78 lits.binaryClauses(constr.get(0), constr.get(1));
79 // solver.getStats().learnedbinaryclauses++;
80 } else {
81 super.learnConstraint(constr);
82 }
83 }
84
85 public Constr createUnregisteredClause(IVecInt literals) {
86 if (literals.size()==1) {
87 return new UnitClause(literals.last());
88 }
89 if (literals.size() == 2) {
90 return new LearntBinaryClause(literals,getVocabulary());
91 }
92 return new LearntHTClause(literals, getVocabulary());
93 }
94 }