Data update

Task/Jaro-similarity/JavaScript/jaro-similarity.js

@@ -0,0 +1,44 @@
+function jaro(s, t) {
+    const s_len = s.length;
+    const t_len = t.length;
+    if (s_len === 0 && t_len === 0) return 1;
+    const match_distance = Math.max(s_len, t_len) / 2 - 1;
+    const s_matches = new Array(s_len).fill(false);
+    const t_matches = new Array(t_len).fill(false);
+    let matches = 0;
+    let transpositions = 0;
+
+    for (let i = 0; i < s_len; i++) {
+        const start = Math.max(0, i - match_distance);
+        const end = Math.min(i + match_distance + 1, t_len);
+        for (let j = start; j < end; j++) {
+            if (t_matches[j]) continue;
+            if (s[i] !== t[j]) continue;
+            s_matches[i] = true;
+            t_matches[j] = true;
+            matches++;
+            break;
+        }
+    }
+
+    if (matches === 0) return 0;
+
+    let k = 0;
+    for (let i = 0; i < s_len; i++) {
+        if (!s_matches[i]) continue;
+        while (!t_matches[k]) k++;
+        if (s[i] !== t[k]) transpositions++;
+        k++;
+    }
+
+    return (
+        (matches / s_len) +
+        (matches / t_len) +
+        ((matches - transpositions / 2) / matches)
+    ) / 3;
+}
+
+// Test cases
+console.log(jaro("MARTHA", "MARHTA"));        // 0.9611111111111111
+console.log(jaro("DIXON", "DICKSONX"));       // 0.8133333333333333
+console.log(jaro("JELLYFISH", "SMELLYFISH")); // 0.8962962962962963