Add a recursive version of the Longest Common Subsequence.

Author: trekhleb

src/algorithms/sets/longest-common-subsequence/__test__/longestCommonSubsequenceRecursive.test.js

@@ -0,0 +1,17 @@
+import longestCommonSubsequence from '../longestCommonSubsequenceRecursive';
+
+describe('longestCommonSubsequenceRecursive', () => {
+  it('should find longest common substring between two strings', () => {
+    expect(longestCommonSubsequence('', '')).toBe('');
+    expect(longestCommonSubsequence('ABC', '')).toBe('');
+    expect(longestCommonSubsequence('', 'ABC')).toBe('');
+    expect(longestCommonSubsequence('ABABC', 'BABCA')).toBe('BABC');
+    expect(longestCommonSubsequence('BABCA', 'ABCBA')).toBe('ABCA');
+    expect(longestCommonSubsequence('sea', 'eat')).toBe('ea');
+    expect(longestCommonSubsequence('algorithms', 'rithm')).toBe('rithm');
+    expect(longestCommonSubsequence(
+      'Algorithms and data structures implemented in JavaScript',
+      'Here you may find Algorithms and data structures that are implemented in JavaScript',
+    )).toBe('Algorithms and data structures implemented in JavaScript');
+  });
+});

src/algorithms/string/longest-common-substring/longestCommonSubstringRecursive.js src/algorithms/sets/longest-common-subsequence/longestCommonSubsequenceRecursive.js

@@ -1,17 +1,17 @@
 /* eslint-disable no-param-reassign */
 /**
- * Longest Common Substring (LCS) (Recursive Approach).
+ * Longest Common Subsequence (LCS) (Recursive Approach).
  *
  * @param {string} string1
  * @param {string} string2
  * @return {number}
  */
-export default function longestCommonSubstringRecursive(string1, string2) {
+export default function longestCommonSubsequenceRecursive(string1, string2) {
   /**
    *
    * @param {string} s1
    * @param {string} s2
-   * @return {string} - returns the LCS (Longest Common Substring)
+   * @return {string} - returns the LCS (Longest Common Subsequence)
    */
   const lcs = (s1, s2, memo = {}) => {
     if (!s1 || !s2) return '';