* Performs cost based filtering w.r.t. each cost dimension.
*
* @throws ContradictionException if a domain is emptied
*/
protected boolean prefilter() throws ContradictionException {
FastPathFinder p = this.graph.getPathFinder();
boolean cont = true;
boolean[] modified;
while (cont) {
modified = p.computeShortestAndLongestPath(toRemove, z, this);
cont = toRemove.size() > 0;
modifiedBound[0] |= modified[0];
modifiedBound[1] |= modified[1];
this.delayedGraphUpdate();