1
impl Solution {
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  pub fn largest_variance(s: String) -> i32 {
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    let au = 'a' as u8;
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    let s = s.into_bytes();
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    let counter = s.iter().fold(vec![0; 26], |mut vec, ch| {
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      vec[(ch - au) as usize] += 1;
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      vec
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    });
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    let mut g_max = 0;
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    for i in 0..26 {
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      for j in 0..26 {
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        if i == j || counter[i] == 0 || counter[j] == 0 {
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          continue;
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        }
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        let (maj, min) = (i as u8 + au, j as u8 + au);
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        let (mut maj_c, mut min_c) = (0, 0);
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        let mut min_r = counter[j];
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        s.iter().for_each(|c| {
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          match c {
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            x if *x == maj => {
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              maj_c += 1;
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            }
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            y if *y == min => {
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              min_c += 1;
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              min_r -= 1;
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            }
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            _ => (),
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          }
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          if min_c > 0 {
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            g_max = g_max.max(maj_c - min_c);
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          }
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          if maj_c < min_c && min_r > 0 {
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            maj_c = 0;
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            min_c = 0;
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          }
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        });
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      }
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    }
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    g_max
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  }
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}