View Javadoc

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.card.AtLeast;
31  import org.sat4j.minisat.constraints.cnf.Clauses;
32  import org.sat4j.minisat.constraints.cnf.LearntWLClause;
33  import org.sat4j.minisat.constraints.cnf.Lits;
34  import org.sat4j.minisat.constraints.cnf.OriginalBinaryClause;
35  import org.sat4j.minisat.constraints.cnf.OriginalWLClause;
36  import org.sat4j.minisat.constraints.cnf.UnitClause;
37  import org.sat4j.minisat.core.Constr;
38  import org.sat4j.minisat.core.ILits;
39  import org.sat4j.specs.ContradictionException;
40  import org.sat4j.specs.IVecInt;
41  
42  /**
43   * @author leberre
44   * @since 2.1
45   */
46  public class MixedDataStructureSingleWL extends AbstractDataStructureFactory {
47  
48  	private static final long serialVersionUID = 1L;
49  
50  	/*
51  	 * (non-Javadoc)
52  	 * 
53  	 * @see
54  	 * org.sat4j.minisat.DataStructureFactory#createCardinalityConstraint(org
55  	 * .sat4j.datatype.VecInt, int)
56  	 */
57  	@Override
58  	public Constr createCardinalityConstraint(IVecInt literals, int degree)
59  			throws ContradictionException {
60  		return AtLeast.atLeastNew(solver, getVocabulary(), literals, degree);
61  	}
62  
63  	/*
64  	 * (non-Javadoc)
65  	 * 
66  	 * @see
67  	 * org.sat4j.minisat.DataStructureFactory#createClause(org.sat4j.datatype
68  	 * .VecInt)
69  	 */
70  	public Constr createClause(IVecInt literals) throws ContradictionException {
71  		IVecInt v = Clauses.sanityCheck(literals, getVocabulary(), solver);
72  		if (v == null) {
73  			// tautological clause
74  			return null;
75  		}
76  		if (v.size() == 1) {
77  			return new UnitClause(v.last());
78  		}
79  		if (v.size() == 2) {
80  			return OriginalBinaryClause.brandNewClause(solver, getVocabulary(),
81  					v);
82  		}
83  		return OriginalWLClause.brandNewClause(solver, getVocabulary(), v);
84  	}
85  
86  	public Constr createUnregisteredClause(IVecInt literals) {
87  		return new LearntWLClause(literals, getVocabulary());
88  	}
89  
90  	@Override
91  	protected ILits createLits() {
92  		return new Lits();
93  	}
94  }