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1   /*
2    * SAT4J: a SATisfiability library for Java Copyright (C) 2004-2006 Daniel Le Berre
3    * 
4    * Based on the original minisat specification from:
5    * 
6    * An extensible SAT solver. Niklas E?n and Niklas S?rensson. Proceedings of the
7    * Sixth International Conference on Theory and Applications of Satisfiability
8    * Testing, LNCS 2919, pp 502-518, 2003.
9    * 
10   * This library is free software; you can redistribute it and/or modify it under
11   * the terms of the GNU Lesser General Public License as published by the Free
12   * Software Foundation; either version 2.1 of the License, or (at your option)
13   * any later version.
14   * 
15   * This library is distributed in the hope that it will be useful, but WITHOUT
16   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
17   * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
18   * details.
19   * 
20   * You should have received a copy of the GNU Lesser General Public License
21   * along with this library; if not, write to the Free Software Foundation, Inc.,
22   * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23   * 
24   */
25  
26  package org.sat4j.minisat.constraints.cnf;
27  
28  import org.sat4j.minisat.core.ILits23;
29  
30  /**
31   * @author leberre To change the template for this generated type comment go to
32   *         Window - Preferences - Java - Code Generation - Code and Comments
33   */
34  public class Lits23 extends Lits2 implements ILits23 {
35  
36      private static final long serialVersionUID = 1L;
37  
38      private TernaryClauses[] ternclauses = null;
39  
40      /**
41       * 
42       */
43      public Lits23() {
44          super();
45      }
46  
47      private void register(int p, int q, int r) {
48          assert p > 1;
49          assert q > 1;
50          assert r > 1;
51  
52          if (ternclauses == null) {
53              ternclauses = new TernaryClauses[2 * nVars() + 2];
54          }
55          if (ternclauses[p] == null) {
56              ternclauses[p] = new TernaryClauses(this, p);
57              watches[p ^ 1].push(ternclauses[p]);
58          }
59          ternclauses[p].addTernaryClause(q, r);
60      }
61  
62      public void ternaryClauses(int lit1, int lit2, int lit3) {
63          register(lit1, lit2, lit3);
64          register(lit2, lit1, lit3);
65          register(lit3, lit1, lit2);
66      }
67  
68      public int nTernaryClauses(int p) {
69          if (ternclauses == null) {
70              return 0;
71          }
72          if (ternclauses[p] == null) {
73              return 0;
74          }
75          return ternclauses[p].size();
76      }
77  }