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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  
29  package org.sat4j.tools.encoding;
30  
31  import org.sat4j.core.VecInt;
32  import org.sat4j.specs.ContradictionException;
33  import org.sat4j.specs.IConstr;
34  import org.sat4j.specs.ISolver;
35  import org.sat4j.specs.IVecInt;
36  
37  /**
38   * The aim of this class is to use different encodings for specific constraints.
39   * The class is abstract because it does not makes sense to use it "as is".
40   * 
41   * @author sroussel
42   * @since 2.3.1
43   */
44  public abstract class EncodingStrategyAdapter {
45  
46  	public IConstr addAtLeast(ISolver solver, IVecInt literals, int degree)
47  			throws ContradictionException {
48  		final int n = literals.size();
49  		IVecInt newLiterals = new VecInt(n);
50  		for (int i = 0; i < n; i++) {
51  			newLiterals.push(-literals.get(i));
52  		}
53  		return this.addAtMost(solver, newLiterals, n - degree);
54  	}
55  
56  	public IConstr addAtLeastOne(ISolver solver, IVecInt literals)
57  			throws ContradictionException {
58  		return solver.addClause(literals);
59  	}
60  
61  	public IConstr addAtMost(ISolver solver, IVecInt literals, int degree)
62  			throws ContradictionException {
63  		return solver.addAtMost(literals, degree);
64  	}
65  
66  	public IConstr addAtMostOne(ISolver solver, IVecInt literals)
67  			throws ContradictionException {
68  		return this.addAtMost(solver, literals, 1);
69  	}
70  
71  	public IConstr addExactly(ISolver solver, IVecInt literals, int degree)
72  			throws ContradictionException {
73  		return solver.addExactly(literals, degree);
74  	}
75  
76  	public IConstr addExactlyOne(ISolver solver, IVecInt literals)
77  			throws ContradictionException {
78  		return this.addExactly(solver, literals, 1);
79  	}
80  
81  	@Override
82  	public String toString() {
83  		return this.getClass().getName();
84  	}
85  
86  }