org.sat4j.csp.Var Maven / Gradle / Ivy
/*******************************************************************************
* 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.
*******************************************************************************/
package org.sat4j.csp;
import org.sat4j.core.VecInt;
import org.sat4j.specs.ContradictionException;
import org.sat4j.specs.ISolver;
import org.sat4j.specs.IVecInt;
public class Var implements Evaluable {
private final Domain domain;
private final String id;
private final int startid;
public Var(String idvar, Domain domain, int lastvarnumber) {
this.domain = domain;
this.id = idvar;
this.startid = lastvarnumber + 1;
}
/*
* (non-Javadoc)
*
* @see org.sat4j.reader.csp.Evaluable#domain()
*/
public Domain domain() {
return domain;
}
/*
* (non-Javadoc)
*
* @see org.sat4j.reader.csp.Evaluable#translate(int)
*/
public int translate(int key) {
return domain.pos(key) + startid;
}
/*
* (non-Javadoc)
*
* @see org.sat4j.reader.csp.Evaluable#toClause(org.sat4j.specs.ISolver)
*/
public void toClause(ISolver solver) throws ContradictionException {
IVecInt clause = new VecInt(domain.size());
for (int i = 0; i < domain.size(); i++)
clause.push(i + startid);
solver.addClause(clause);
solver.addAtMost(clause, 1);
}
public int findValue(int[] model) {
for (int i = 0; i < domain.size(); i++) {
int varnum = i + startid;
if (model[varnum - 1] == varnum)
return domain.get(i);
}
throw new RuntimeException("BIG PROBLEM: no value for a var!");
}
/*
* (non-Javadoc)
*
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
return id;
}
}