private void useValue(int i) throws ContradictionException {
int mate = swapValue_BFS(i);
if (mate != -1) {
flow[mate]--;
flow[i]++;
int tmp = mate;
while (tmp != i) {
digraph.removeArc(tmp, father[tmp]);
digraph.addArc(father[tmp], tmp);
tmp = father[tmp];
}
} else {
contradiction(null, "no match");
}
}
private void assignVariable(int i) throws ContradictionException {
int mate = augmentPath_BFS(i);
if (mate != -1) {
flow[mate]++;
flow[i]++;
int tmp = mate;
while (tmp != i) {
digraph.removeArc(father[tmp], tmp);
digraph.addArc(tmp, father[tmp]);
tmp = father[tmp];
}
} else {
contradiction(vars[i], "no match");
}
}
private boolean canUnuseValue(int i) {
int mate = augmentPath_BFS(i);
if (mate != -1) {
flow[mate]++;
flow[i]--;
int tmp = mate;
while (tmp != i) {
digraph.removeArc(father[tmp], tmp);
digraph.addArc(tmp, father[tmp]);
tmp = father[tmp];
}
return true;
} else {
return false;
}
}
private void filter() throws ContradictionException {
buildSCC();
int j, ub;
IntVar v;
for (int i = 0; i < n; i++) {
v = vars[i];
ub = v.getUB();
if (v.getLB() != ub) { // i.e. v is not instantiated
for (int k = v.getLB(); k <= ub; k = v.nextValue(k)) {
j = map.get(k);
if (nodeSCC[i] != nodeSCC[j]) {
if (digraph.arcExists(j, i)) {
v.instantiateTo(k, aCause);
ISet nei = digraph.getSuccessorsOf(i);
for (int s = nei.getFirstElement(); s >= 0; s = nei.getNextElement()) {
digraph.removeArc(i, s);
}
} else {
v.removeValue(k, aCause);
digraph.removeArc(i, j);
}
}
}
}
}
int nb = boundedVariables.size();
for (int i = 0; i < nb; i++) {
v = vars[boundedVariables.get(i)];
ub = v.getUB();
for (int k = v.getLB(); k <= ub; k++) {
j = map.get(k);
if (!(digraph.arcExists(i, j) || digraph.arcExists(j, i))) {
v.removeValue(k, aCause);
}
}
int lb = v.getLB();
for (int k = v.getUB(); k >= lb; k--) {
j = map.get(k);
if (!(digraph.arcExists(i, j) || digraph.arcExists(j, i))) {
v.removeValue(k, aCause);
}
}
}
// filter cardinality variables
int idx;
ISet nei;
for (int i = 0; i < values.length; i++) {
idx = map.get(values[i]);
nei = digraph.getSuccessorsOf(idx);
ub = nei.getSize() + digraph.getPredecessorsOf(idx).getSize();
cards[i].updateUpperBound(ub, aCause);
}
for (int i = 0; i < values.length; i++) {
idx = map.get(values[i]);
int size = digraph.getSuccessorsOf(idx).getSize();
ub = cards[i].getUB();
while (size < ub && canUseValue(idx)) {
size++;
}
cards[i].updateUpperBound(size, aCause);
}
for (int i = 0; i < values.length; i++) {
idx = map.get(values[i]);
while (canUnuseValue(idx)) {}
cards[i].updateLowerBound(digraph.getSuccessorsOf(idx).getSize(), aCause);
}
}