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1   /*******************************************************************************
2    * SAT4J: a SATisfiability library for Java Copyright (C) 2004, 2012 Artois University and CNRS
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   * Contributors:
28   *   CRIL - initial API and implementation
29   *******************************************************************************/
30  package org.sat4j.tools;
31  
32  import java.util.Collection;
33  import java.util.HashMap;
34  import java.util.Map;
35  
36  import org.sat4j.core.VecInt;
37  import org.sat4j.specs.ContradictionException;
38  import org.sat4j.specs.IConstr;
39  import org.sat4j.specs.ISolver;
40  import org.sat4j.specs.IVecInt;
41  
42  public class FullClauseSelectorSolver<T extends ISolver> extends
43          AbstractClauseSelectorSolver<T> {
44  
45      /**
46       * 
47       */
48      private static final long serialVersionUID = 1L;
49      private final Map<Integer, IConstr> constrs = new HashMap<Integer, IConstr>();
50      private final IVecInt lastClause = new VecInt();
51      private IConstr lastConstr;
52      private final boolean skipDuplicatedEntries;
53  
54      public FullClauseSelectorSolver(T solver, boolean skipDuplicatedEntries) {
55          super(solver);
56          this.skipDuplicatedEntries = skipDuplicatedEntries;
57      }
58  
59      public IConstr addControlableClause(IVecInt literals)
60              throws ContradictionException {
61          if (this.skipDuplicatedEntries) {
62              if (literals.equals(this.lastClause)) {
63                  return null;
64              }
65              this.lastClause.clear();
66              literals.copyTo(this.lastClause);
67          }
68          int newvar = createNewVar(literals);
69          literals.push(newvar);
70          this.lastConstr = super.addClause(literals);
71          if (this.lastConstr == null) {
72              discardLastestVar();
73          } else {
74              this.constrs.put(newvar, this.lastConstr);
75          }
76          return this.lastConstr;
77      }
78  
79      public IConstr addNonControlableClause(IVecInt literals)
80              throws ContradictionException {
81          return super.addClause(literals);
82      }
83  
84      @Override
85      public IConstr addClause(IVecInt literals) throws ContradictionException {
86          return addControlableClause(literals);
87      }
88  
89      @Override
90      public int[] model() {
91          int[] fullmodel = super.modelWithInternalVariables();
92          if (fullmodel == null) {
93              return null;
94          }
95          int[] model = new int[fullmodel.length - this.constrs.size()];
96          int j = 0;
97          for (int element : fullmodel) {
98              if (this.constrs.get(Math.abs(element)) == null) {
99                  model[j++] = element;
100             }
101         }
102         return model;
103     }
104 
105     /**
106      * 
107      * @since 2.1
108      */
109     public Collection<IConstr> getConstraints() {
110         return this.constrs.values();
111     }
112 
113     @Override
114     public Collection<Integer> getAddedVars() {
115         return this.constrs.keySet();
116     }
117 
118     public IConstr getLastConstr() {
119         return lastConstr;
120     }
121 
122     public void setLastConstr(IConstr lastConstr) {
123         this.lastConstr = lastConstr;
124     }
125 
126     public Map<Integer, IConstr> getConstrs() {
127         return constrs;
128     }
129 
130     public IVecInt getLastClause() {
131         return lastClause;
132     }
133 
134     public boolean isSkipDuplicatedEntries() {
135         return skipDuplicatedEntries;
136     }
137 
138 }