RosettaCodeData/Task/Jaro-similarity/Rust/jaro-similarity.rust
2023-07-01 13:44:08 -04:00

41 lines
1.3 KiB
Text

use std::cmp;
pub fn jaro(s1: &str, s2: &str) -> f64 {
let s1_len = s1.len();
let s2_len = s2.len();
if s1_len == 0 && s2_len == 0 { return 1.0; }
let match_distance = cmp::max(s1_len, s2_len) / 2 - 1;
let mut s1_matches = vec![false; s1_len];
let mut s2_matches = vec![false; s2_len];
let mut m: isize = 0;
for i in 0..s1_len {
let start = cmp::max(0, i as isize - match_distance as isize) as usize;
let end = cmp::min(i + match_distance + 1, s2_len);
for j in start..end {
if !s2_matches[j] && s1.as_bytes()[i] == s2.as_bytes()[j] {
s1_matches[i] = true;
s2_matches[j] = true;
m += 1;
break;
}
}
}
if m == 0 { return 0.0; }
let mut t = 0.0;
let mut k = 0;
for i in 0..s1_len {
if s1_matches[i] {
while !s2_matches[k] { k += 1; }
if s1.as_bytes()[i] != s2.as_bytes()[k] { t += 0.5; }
k += 1;
}
}
let m = m as f64;
(m / s1_len as f64 + m / s2_len as f64 + (m - t) / m) / 3.0
}
fn main() {
let pairs = [("MARTHA", "MARHTA"), ("DIXON", "DICKSONX"), ("JELLYFISH", "SMELLYFISH")];
for p in pairs.iter() { println!("{}/{} = {}", p.0, p.1, jaro(p.0, p.1)); }
}