/*******************************************************************************
* SAT4J: a SATisfiability library for Java Copyright (C) 2004-2008 Daniel Le Berre
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU Lesser General Public License Version 2.1 or later (the
* "LGPL"), in which case the provisions of the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of the LGPL, and not to allow others to use your version of
* this file under the terms of the EPL, indicate your decision by deleting
* the provisions above and replace them with the notice and other provisions
* required by the LGPL. If you do not delete the provisions above, a recipient
* may use your version of this file under the terms of the EPL or the LGPL.
*
* Based on the original MiniSat specification from:
*
* An extensible SAT solver. Niklas Een and Niklas Sorensson. Proceedings of the
* Sixth International Conference on Theory and Applications of Satisfiability
* Testing, LNCS 2919, pp 502-518, 2003.
*
* See www.minisat.se for the original solver in C++.
*
*******************************************************************************/
package org.sat4j.minisat.constraints.cnf;
import java.io.Serializable;
import org.sat4j.core.VecInt;
import org.sat4j.minisat.core.Constr;
import org.sat4j.minisat.core.ILits;
import org.sat4j.minisat.core.UnitPropagationListener;
import org.sat4j.specs.IVecInt;
/**
* @author leberre To change the template for this generated type comment go to
* Window - Preferences - Java - Code Generation - Code and Comments
*/
public class TernaryClauses implements Constr, Serializable {
private static final long serialVersionUID = 1L;
private final IVecInt stubs = new VecInt();
private final ILits voc;
private final int phead;
public TernaryClauses(ILits voc, int p) {
this.voc = voc;
this.phead = p;
}
public void addTernaryClause(int a, int b) {
stubs.push(a);
stubs.push(b);
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#remove()
*/
public void remove() {
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#propagate(org.sat4j.minisat.UnitPropagationListener,
* int)
*/
public boolean propagate(UnitPropagationListener s, int p) {
assert voc.isSatisfied(p);
assert voc.isFalsified(phead);
voc.attach(p, this);
for (int i = 0; i < stubs.size(); i += 2) {
int a = stubs.get(i);
int b = stubs.get(i + 1);
if (voc.isSatisfied(a) || voc.isSatisfied(b)) {
continue;
}
if (voc.isFalsified(a) && !s.enqueue(b, this)) {
return false;
} else if (voc.isFalsified(b) && !s.enqueue(a, this)) {
return false;
}
}
return true;
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#simplify()
*/
public boolean simplify() {
return false;
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#undo(int)
*/
public void undo(int p) {
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#calcReason(int, org.sat4j.datatype.VecInt)
*/
public void calcReason(int p, IVecInt outReason) {
assert voc.isFalsified(this.phead);
if (p == ILits.UNDEFINED) {
int i = 0;
while (!voc.isFalsified(stubs.get(i))
|| !voc.isFalsified(stubs.get(i + 1))) {
i += 2;
}
outReason.push(this.phead ^ 1);
outReason.push(stubs.get(i) ^ 1);
outReason.push(stubs.get(i + 1) ^ 1);
} else {
outReason.push(this.phead ^ 1);
int i = 0;
while ((stubs.get(i) != p) || (!voc.isFalsified(stubs.get(i ^ 1)))) {
i++;
}
assert !voc.isFalsified(stubs.get(i));
outReason.push(stubs.get(i ^ 1) ^ 1);
assert voc.isFalsified(stubs.get(i ^ 1));
}
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#learnt()
*/
public boolean learnt() {
return false;
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#incActivity(double)
*/
public void incActivity(double claInc) {
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#getActivity()
*/
public double getActivity() {
return 0;
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#locked()
*/
public boolean locked() {
// TODO Auto-generated method stub
return false;
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#setLearnt()
*/
public void setLearnt() {
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#register()
*/
public void register() {
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#rescaleBy(double)
*/
public void rescaleBy(double d) {
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#size()
*/
public int size() {
return stubs.size();
}
/*
* (non-Javadoc)
*
* @see org.sat4j.minisat.Constr#get(int)
*/
public int get(int i) {
throw new UnsupportedOperationException();
}
public void assertConstraint(UnitPropagationListener s) {
throw new UnsupportedOperationException();
}
}