public boolean retainAll(final IntList c){boolean rval = false;for (int j = 0; j < _limit; ){if (!c.contains(_array[ j ])){remove(j);rval = true;}else{j++;}}return rval;}
public bool RetainAll(IntList c){bool rval = false;for (int j = 0; j < _limit; ){if (!c.Contains(_array[j])){Remove(j);rval = true;}else{j++;}}return rval;}