def count
import bend-collections@1.0.0.0/src/containers/bitset.bend as Bitsetimport Base
import bend-collections@1.0.0.0/src/math/pow2.bend as P2
278def count(s: Bitset) -> Bitset & Nat:
279 match s:
280 case BS{+n, +d, a}:
281 count_fin(count_go(P2.pow2t(d), (a, 0n), d, 0n), n, d)