Crate fid[][src]

FID (Fully Indexable Dictionary) implementation for Rust

This crate provides a succinct bit vector that supports two kinds of bit operations in constant-time:

  • rank(i) computes the number of 0s (or 1s) in [0..i)
  • select(r) locates the (r+1)-th position of 0 (or 1).

Structures supporting these two operations are called FID (fully indexable dictionary).

Basic usage

use fid::{BitVector, FID};
let mut bv = BitVector::new();
// 01101101
bv.push(false); bv.push(true); bv.push(true); bv.push(false);
bv.push(true); bv.push(true); bv.push(false); bv.push(true);
assert_eq!(bv.rank0(5), 2);
assert_eq!(bv.rank1(5), 3);
assert_eq!(bv.select0(2), 6);
assert_eq!(bv.select1(2), 4);

About implementation

Compression and computation algorithms for BitVector are originally from [1] and its practical implementation ideas are from [2].

[1] Gonzalo Navarro and Eliana Providel. 2012. Fast, small, simple rank/select on bitmaps. In Proceedings of the 11th international conference on Experimental Algorithms (SEA'12), Ralf Klasing (Ed.). Springer-Verlag, Berlin, Heidelberg, 295-306. DOI=

[2] rsdic by Daisuke Okanohara.


pub use bit_array::BitArray;
pub use bit_vector::BitVector;
pub use fid::FID;