Add solution #1143

Author: JoshCrozier

README.md

@@ -397,6 +397,7 @@
 1108|[Defanging an IP Address](./1108-defanging-an-ip-address.js)|Easy|
 1122|[Relative Sort Array](./1122-relative-sort-array.js)|Easy|
 1137|[N-th Tribonacci Number](./1137-n-th-tribonacci-number.js)|Easy|
+1143|[Longest Common Subsequence](./1143-longest-common-subsequence.js)|Medium|
 1161|[Maximum Level Sum of a Binary Tree](./1161-maximum-level-sum-of-a-binary-tree.js)|Medium|
 1189|[Maximum Number of Balloons](./1189-maximum-number-of-balloons.js)|Easy|
 1200|[Minimum Absolute Difference](./1200-minimum-absolute-difference.js)|Easy|

solutions/1143-longest-common-subsequence.js

@@ -0,0 +1,37 @@
+/**
+ * 1143. Longest Common Subsequence
+ * https://leetcode.com/problems/longest-common-subsequence/
+ * Difficulty: Medium
+ *
+ * Given two strings text1 and text2, return the length of their longest common subsequence.
+ * If there is no common subsequence, return 0.
+ *
+ * A subsequence of a string is a new string generated from the original string with some
+ * characters (can be none) deleted without changing the relative order of the remaining
+ * characters.
+ *
+ * - For example, "ace" is a subsequence of "abcde".
+ *
+ * A common subsequence of two strings is a subsequence that is common to both strings.
+ */
+
+/**
+ * @param {string} text1
+ * @param {string} text2
+ * @return {number}
+ */
+var longestCommonSubsequence = function(text1, text2) {
+  const dp = new Array(text1.length + 1).fill(0).map(() => new Array(text2.length + 1).fill(0));
+
+  for (let i = 1; i <= text1.length; i++) {
+    for (let j = 1; j <= text2.length; j++) {
+      if (text1.charAt(i - 1) === text2.charAt(j - 1)) {
+        dp[i][j] = dp[i - 1][j - 1] + 1;
+      } else {
+        dp[i][j] = Math.max(dp[i - 1][j], dp[i][j - 1]);
+      }
+    }
+  }
+
+  return dp[text1.length][text2.length];
+};