融合几种独立结构的混合结构。
===Bit array ===
A bit array (also known as bit map , bit set, bit string, or bit vector) is an array data structure that compactly stores bits. It can be used to implement a simple set data structure.
https://en.wikipedia.org/wiki/Bit_array
=== Roaring ===
# Lakshminarasimhan, Sriram, et al. "Scalable in situ scientific data encoding for analytical query processing." HPDC 2013.
== SDSL - Succinct Data Structure Library ==