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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 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.Lits23;
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.ILits23;
38  import org.sat4j.specs.ContradictionException;
39  import org.sat4j.specs.IVecInt;
40  
41  /**
42   * @author leberre
43   */
44  public class MixedDataStructureWithBinaryAndTernary extends
45          AbstractDataStructureFactory<ILits23> {
46  
47      private static final long serialVersionUID = 1L;
48  
49  
50      /*
51       * (non-Javadoc)
52       * 
53       * @see org.sat4j.minisat.DataStructureFactory#createClause(org.sat4j.datatype.VecInt)
54       */
55       public Constr createClause(IVecInt literals) throws ContradictionException {
56          IVecInt v = Clauses.sanityCheck(literals, lits, solver);
57          if (v == null)
58              return null;
59          if (v.size() == 2) {
60              lits.binaryClauses(v.get(0), v.get(1));
61              return null;
62          }
63          if (v.size() == 3) {
64              lits.ternaryClauses(v.get(0), v.get(1), v.get(2));
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 if (constr.size() == 3) {
81              lits.ternaryClauses(constr.get(0), constr.get(1), constr.get(2));
82              // solver.getStats().learnedternaryclauses++;
83          } else {
84              super.learnConstraint(constr);
85          }
86      }
87  
88      @Override
89      protected ILits23 createLits() {
90          return new Lits23();
91      }
92  
93      public Constr createUnregisteredClause(IVecInt literals) {
94      	if (literals.size()==1) {
95      		return new UnitClause(literals.last());
96      	}
97      	if (literals.size() == 2) {
98              return new LearntBinaryClause(literals,getVocabulary());
99          }
100         return new LearntHTClause(literals, getVocabulary());
101     }
102 
103 }