presto-main/src/main/java/io/prestosql/type/setdigest/SetDigest.java/SetDigest/SetDigest
class SetDigest:    public SetDigest(int maxHashes, int numHllBuckets)
    {
        this(maxHashes, HyperLogLog.newInstance(numHllBuckets), new Long2ShortRBTreeMap());
    }