for (int it=0; it<iter; it++) {
for (int i=0; i<numSets; i++) {
if (impl=="open") {
final OpenBitSet set = osets[i];
final OpenBitSetIterator iterator = new OpenBitSetIterator(set);
for(int next=iterator.nextDoc(); next>=0; next=iterator.nextDoc()) {
ret += next;
}
} else {
final BitSet set = sets[i];
for(int next=set.nextSetBit(0); next>=0; next=set.nextSetBit(next+1)) {