040000 tree 1f222a811bb4292b34b41fe8668750887248b0a8	frequencies
040000 tree fc3d6138b43c1b4285c17d8123d4029747f7d3e0	hash
040000 tree ab8bb247b46cac87acaba47bb1179ccf7da435f8	hll
040000 tree 5800836fd24b5e1854cf6dabe2b222f6628fe151	quantiles
040000 tree cbb70c20d2daedfdca1a2da55bb8cb171689562d	sampling
040000 tree 0ee6eba54368f2146471d3b95b8aa29fc7b831ea	theta
040000 tree dbd1c412fe9e21d146003ba021681b4ac65f3c78	tuple