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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.minisat.orders;
31  
32  import org.sat4j.minisat.core.Heap;
33  
34  public class SubsetVarOrder extends VarOrderHeap {
35  
36      private final int[] varsToTest;
37  
38      public SubsetVarOrder(int[] varsToTest) {
39          this.varsToTest = new int[varsToTest.length];
40          System.arraycopy(varsToTest, 0, this.varsToTest, 0, varsToTest.length);
41      }
42  
43      /**
44  	 * 
45  	 */
46      private static final long serialVersionUID = 1L;
47  
48      @Override
49      public void init() {
50          int nlength = this.lits.nVars() + 1;
51          if (this.activity == null || this.activity.length < nlength) {
52              this.activity = new double[nlength];
53          }
54          this.phaseStrategy.init(nlength);
55          this.activity[0] = -1;
56          this.heap = new Heap(this.activity);
57          this.heap.setBounds(nlength);
58          for (int var : this.varsToTest) {
59              assert var > 0;
60              assert var <= this.lits.nVars() : "" + this.lits.nVars() + "/" + var; //$NON-NLS-1$ //$NON-NLS-2$
61              this.activity[var] = 0.0;
62              if (this.lits.belongsToPool(var)) {
63                  this.heap.insert(var);
64              }
65          }
66      }
67  }