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
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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
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18 *******************************************************************************/
19 package org.sat4j.csp.constraints;
20
21 import org.sat4j.core.VecInt;
22 import org.sat4j.csp.Clausifiable;
23 import org.sat4j.csp.Evaluable;
24 import org.sat4j.csp.Var;
25 import org.sat4j.specs.ContradictionException;
26 import org.sat4j.specs.ISolver;
27 import org.sat4j.specs.IVec;
28 import org.sat4j.specs.IVecInt;
29 import org.sat4j.specs.IteratorInt;
30
31 public class AllDiff implements Clausifiable {
32
33 public void toClause(ISolver solver, IVec<Var> scope, IVec<Evaluable> vars)
34 throws ContradictionException {
35 int n = scope.size();
36 IVecInt clause = new VecInt();
37 int vali,valj;
38 for (int i = 0; i < n; i++) {
39 Var vi = scope.get(i);
40 for (int j = i + 1; j < n; j++) {
41 // make all values differents
42 Var vj = scope.get(j);
43 for (IteratorInt iti = vi.domain().iterator(); iti.hasNext();) {
44 vali = iti.next();
45 for (IteratorInt itj = vj.domain().iterator(); itj.hasNext();) {
46 valj = itj.next();
47 // the two variables share a common value
48 if (vali == valj) {
49 clause.push(-vi.translate(vali));
50 clause.push(-vj.translate(valj));
51 solver.addClause(clause);
52 clause.clear();
53 }
54 }
55 }
56 }
57 }
58 }
59
60 }