aoc/util/bitset.rs
1//! Add a `biterator` method that treats an integer as a set, iterating over each element where
2//! the respective bit is set. For example `1101` would return 0, 2 and 3.
3use crate::util::integer::*;
4
5pub trait BitOps<T> {
6 #[must_use]
7 fn biterator(self) -> Bitset<T>;
8}
9
10impl<T: Integer<T>> BitOps<T> for T {
11 fn biterator(self) -> Bitset<T> {
12 Bitset { t: self }
13 }
14}
15
16pub struct Bitset<T> {
17 t: T,
18}
19
20impl<T: Integer<T>> Iterator for Bitset<T> {
21 type Item = usize;
22
23 #[inline]
24 fn next(&mut self) -> Option<Self::Item> {
25 let low = self.t.lowest_one()?;
26 self.t = self.t ^ (T::ONE << low);
27 Some(low as usize)
28 }
29}