1
impl Solution {
2
  pub fn word_subsets(a: Vec<String>, b: Vec<String>) -> Vec<String> {
3
    let count = |s: &str| {
4
      let mut m = [0; 26];
5
      s.chars().for_each(|c| m[c as usize - 'a' as usize] += 1);
6
      m
7
    };
8
    let b_counts = b.iter().map(|s| count(s)).fold([0; 26], |mut bm, m| {
9
      m.iter()
10
        .enumerate()
11
        .for_each(|(i, &n)| bm[i] = bm[i].max(n));
12
      bm
13
    });
14

15
    a.into_iter()
16
      .map(|w| (count(&w), w))
17
      .filter(|(m, _)| b_counts.iter().enumerate().all(|(i, &n)| m[i] >= n))
18
      .map(|(_, w)| w)
19
      .collect()
20
  }
21
}