private void ruin(
Collection<VehicleRoute> vehicleRoutes, int nOfJobs2BeRemoved, List<Job> unassignedJobs) {
if (vrp.getJobs().values().size() == 0) return;
Map<Job, VehicleRoute> mappedRoutes = map(vehicleRoutes);
int toRemove = nOfJobs2BeRemoved;
Collection<Job> lastRemoved = new ArrayList<Job>();
Set<VehicleRoute> ruined = new HashSet<VehicleRoute>();
Set<Job> removed = new HashSet<Job>();
Set<VehicleRoute> cycleCandidates = new HashSet<VehicleRoute>();
while (toRemove > 0) {
Job target;
VehicleRoute targetRoute = null;
if (lastRemoved.isEmpty()) {
target = RandomUtils.nextJob(vrp.getJobs().values(), random);
targetRoute = mappedRoutes.get(target);
} else {
target = RandomUtils.nextJob(lastRemoved, random);
Iterator<Job> neighborIterator =
jobNeighborhoods.getNearestNeighborsIterator(nOfJobs2BeRemoved, target);
while (neighborIterator.hasNext()) {
Job j = neighborIterator.next();
if (!removed.contains(j) && !ruined.contains(mappedRoutes.get(j))) {
targetRoute = mappedRoutes.get(j);
break;
}
}
lastRemoved.clear();
}
if (targetRoute == null) break;
if (cycleCandidates.contains(targetRoute)) break;
if (ruined.contains(targetRoute)) {
cycleCandidates.add(targetRoute);
break;
}
DBSCANClusterer dbscan = new DBSCANClusterer(vrp.getTransportCosts());
dbscan.setRandom(random);
dbscan.setMinPts(minPts);
dbscan.setEpsFactor(epsFactor);
List<Job> cluster = dbscan.getRandomCluster(targetRoute);
for (Job j : cluster) {
if (toRemove == 0) break;
if (removeJob(j, vehicleRoutes)) {
lastRemoved.add(j);
unassignedJobs.add(j);
}
toRemove--;
}
ruined.add(targetRoute);
}
}
private Collection<Job> ruinRoutes_(
Collection<VehicleRoute> vehicleRoutes,
Job targetJob,
int nOfJobs2BeRemoved,
Set<Job> available) {
List<Job> unassignedJobs = new ArrayList<Job>();
int nNeighbors = nOfJobs2BeRemoved - 1;
removeJob(targetJob, vehicleRoutes);
unassignedJobs.add(targetJob);
Iterator<Job> neighborhoodIterator =
jobNeighborhoods.getNearestNeighborsIterator(nNeighbors, targetJob);
while (neighborhoodIterator.hasNext()) {
Job job = neighborhoodIterator.next();
if (available != null) available.remove(job);
if (removeJob(job, vehicleRoutes)) {
unassignedJobs.add(job);
}
}
return unassignedJobs;
}
