28 lines
637 B
Rust
28 lines
637 B
Rust
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use std::cmp;
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use std::collections::HashMap;
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impl Solution {
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fn get_freqs(s: &str) -> HashMap<char, usize> {
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let mut freqs = HashMap::new();
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for c in s.chars() {
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*freqs.entry(c).or_insert(0) += 1;
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}
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freqs
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}
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pub fn frequency_sort(mut s: String) -> String {
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let mut freqs: Vec<(char, usize)> = Solution::get_freqs(&s).into_iter().collect();
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freqs.sort_by_key(|(_, count)| cmp::Reverse(*count));
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freqs.into_iter().fold(String::new(), |mut s, (c, n)| {
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for _ in 0..n {
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s.push(c);
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}
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s
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})
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}
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}
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