Data update

Task/Levenshtein-distance-Alignment/JavaScript/levenshtein-distance-alignment.js

@@ -0,0 +1,50 @@
+class LevenshteinAlignment {
+    static alignment(a, b) {
+        a = a.toLowerCase();
+        b = b.toLowerCase();
+
+        // Initialize costs matrix
+        const costs = Array(a.length + 1).fill().map(() => Array(b.length + 1).fill(0));
+
+        // Fill first row and column
+        for (let j = 0; j <= b.length; j++) {
+            costs[0][j] = j;
+        }
+        for (let i = 1; i <= a.length; i++) {
+            costs[i][0] = i;
+            for (let j = 1; j <= b.length; j++) {
+                costs[i][j] = Math.min(
+                    1 + Math.min(costs[i - 1][j], costs[i][j - 1]),
+                    a[i - 1] === b[j - 1] ? costs[i - 1][j - 1] : costs[i - 1][j - 1] + 1
+                );
+            }
+        }
+
+        // Walk back through matrix to figure out path
+        let aPathRev = [];
+        let bPathRev = [];
+        for (let i = a.length, j = b.length; i !== 0 && j !== 0;) {
+            if (costs[i][j] === (a[i - 1] === b[j - 1] ? costs[i - 1][j - 1] : costs[i - 1][j - 1] + 1)) {
+                aPathRev.push(a[--i]);
+                bPathRev.push(b[--j]);
+            } else if (costs[i][j] === 1 + costs[i - 1][j]) {
+                aPathRev.push(a[--i]);
+                bPathRev.push('-');
+            } else if (costs[i][j] === 1 + costs[i][j - 1]) {
+                aPathRev.push('-');
+                bPathRev.push(b[--j]);
+            }
+        }
+
+        // Reverse and join arrays to form strings
+        return [
+            aPathRev.reverse().join(''),
+            bPathRev.reverse().join('')
+        ];
+    }
+}
+
+// Example usage
+const result = LevenshteinAlignment.alignment("rosettacode", "raisethysword");
+console.log(result[0]);
+console.log(result[1]);