dsalgo/
bits_mask_less_than.rs

1pub fn bit_mask(less_than: usize) -> usize {
2    (1 << less_than) - 1
3}
4
5#[cfg(test)]
6
7mod tests {
8
9    use super::*;
10
11    #[test]
12
13    fn test() {
14        assert_eq!(bit_mask(4), 0b001111);
15    }
16}