/**
* Copyright (c) 1999-2014, Ecole des Mines de Nantes
* All rights reserved.
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* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the Ecole des Mines de Nantes nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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*/
/**
* Created by IntelliJ IDEA.
* User: Jean-Guillaume Fages
* Date: 14/01/13
* Time: 16:36
*/
package solver.constraints.set;
import gnu.trove.map.hash.THashMap;
import solver.Solver;
import solver.constraints.Propagator;
import solver.constraints.PropagatorPriority;
import solver.exception.ContradictionException;
import solver.variables.SetVar;
import solver.variables.delta.ISetDeltaMonitor;
import solver.variables.events.PropagatorEventType;
import solver.variables.events.SetEventType;
import util.ESat;
import util.procedure.IntProcedure;
import util.tools.ArrayUtils;
public class PropUnion extends Propagator<SetVar> {
//***********************************************************************************
// VARIABLES
//***********************************************************************************
private int k;
private ISetDeltaMonitor[] sdm;
private IntProcedure unionForced, unionRemoved, setForced, setRemoved;
//***********************************************************************************
// CONSTRUCTORS
//***********************************************************************************
/**
* The union of sets is equal to union
*
* @param sets
* @param union
*/
public PropUnion(SetVar[] sets, SetVar union) {
super(ArrayUtils.append(sets, new SetVar[]{union}), PropagatorPriority.LINEAR, true);
k = sets.length;
sdm = new ISetDeltaMonitor[k + 1];
for (int i = 0; i <= k; i++) {
sdm[i] = this.vars[i].monitorDelta(this);
}
// PROCEDURES
unionForced = new IntProcedure() {
@Override
public void execute(int element) throws ContradictionException {
int mate = -1;
for (int i = 0; i < k && mate != -2; i++) {
if (vars[i].envelopeContains(element)) {
if (mate == -1) {
mate = i;
} else {
mate = -2;
}
}
}
if (mate == -1) {
contradiction(vars[k], "");
} else if (mate != -2) {
vars[mate].addToKernel(element, aCause);
}
}
};
unionRemoved = new IntProcedure() {
@Override
public void execute(int element) throws ContradictionException {
for (int i = 0; i < k; i++) {
vars[i].removeFromEnvelope(element, aCause);
}
}
};
setForced = new IntProcedure() {
@Override
public void execute(int element) throws ContradictionException {
vars[k].addToKernel(element, aCause);
}
};
setRemoved = new IntProcedure() {
@Override
public void execute(int element) throws ContradictionException {
if (vars[k].envelopeContains(element)) {
int mate = -1;
for (int i = 0; i < k && mate != -2; i++) {
if (vars[i].envelopeContains(element)) {
if (mate == -1) {
mate = i;
} else {
mate = -2;
}
}
}
if (mate == -1) {
vars[k].removeFromEnvelope(element, aCause);
} else if (mate != -2 && vars[k].kernelContains(element)) {
vars[mate].addToKernel(element, aCause);
}
}
}
};
}
//***********************************************************************************
// METHODS
//***********************************************************************************
@Override
public void propagate(int evtmask) throws ContradictionException {
if (PropagatorEventType.isFullPropagation(evtmask)) {
SetVar union = vars[k];
for (int i = 0; i < k; i++) {
for (int j = vars[i].getKernelFirst(); j != SetVar.END; j = vars[i].getKernelNext())
union.addToKernel(j, aCause);
for (int j = vars[i].getEnvelopeFirst(); j != SetVar.END; j = vars[i].getEnvelopeNext())
if (!union.envelopeContains(j))
vars[i].removeFromEnvelope(j, aCause);
}
for (int j = union.getEnvelopeFirst(); j != SetVar.END; j = union.getEnvelopeNext()) {
if (union.kernelContains(j)) {
int mate = -1;
for (int i = 0; i < k && mate != -2; i++) {
if (vars[i].envelopeContains(j)) {
if (mate == -1) {
mate = i;
} else {
mate = -2;
}
}
}
if (mate == -1) {
contradiction(vars[k], "");
} else if (mate != -2) {
vars[mate].addToKernel(j, aCause);
}
} else {
int mate = -1;
for (int i = 0; i < k; i++) {
if (vars[i].envelopeContains(j)) {
mate = i;
break;
}
}
if (mate == -1) union.removeFromEnvelope(j, aCause);
}
}
// ------------------
for (int i = 0; i <= k; i++)
sdm[i].unfreeze();
}
}
@Override
public void propagate(int idxVarInProp, int mask) throws ContradictionException {
sdm[idxVarInProp].freeze();
if (idxVarInProp < k) {
sdm[idxVarInProp].forEach(setForced, SetEventType.ADD_TO_KER);
sdm[idxVarInProp].forEach(setRemoved, SetEventType.REMOVE_FROM_ENVELOPE);
} else {
sdm[idxVarInProp].forEach(unionForced, SetEventType.ADD_TO_KER);
sdm[idxVarInProp].forEach(unionRemoved, SetEventType.REMOVE_FROM_ENVELOPE);
}
sdm[idxVarInProp].unfreeze();
}
@Override
public ESat isEntailed() {
for (int i = 0; i < k; i++) {
for (int j = vars[i].getKernelFirst(); j != SetVar.END; j = vars[i].getKernelNext())
if (!vars[k].envelopeContains(j))
return ESat.FALSE;
}
for (int j = vars[k].getKernelFirst(); j != SetVar.END; j = vars[k].getKernelNext()) {
int mate = -1;
for (int i = 0; i < k; i++)
if (vars[i].envelopeContains(j)) {
mate = i;
break;
}
if (mate == -1) return ESat.FALSE;
}
if (isCompletelyInstantiated()) return ESat.TRUE;
return ESat.UNDEFINED;
}
@Override
public void duplicate(Solver solver, THashMap<Object, Object> identitymap) {
if (!identitymap.containsKey(this)) {
int size = vars.length - 1;
SetVar[] svars = new SetVar[size];
for (int i = 0; i < size; i++) {
vars[i].duplicate(solver, identitymap);
svars[i] = (SetVar) identitymap.get(vars[i]);
}
vars[size].duplicate(solver, identitymap);
SetVar svar = (SetVar) identitymap.get(vars[size]);
identitymap.put(this, new PropUnion(svars, svar));
}
}
}