Add solution #646

Author: JoshCrozier

0646-maximum-length-of-pair-chain.js

@@ -0,0 +1,33 @@
+/**
+ * 646. Maximum Length of Pair Chain
+ * https://leetcode.com/problems/maximum-length-of-pair-chain/
+ * Difficulty: Medium
+ *
+ * You are given an array of n pairs pairs where pairs[i] = [lefti, righti] and lefti < righti.
+ *
+ * A pair p2 = [c, d] follows a pair p1 = [a, b] if b < c. A chain of pairs can be formed in
+ * this fashion.
+ *
+ * Return the length longest chain which can be formed.
+ *
+ * You do not need to use up all the given intervals. You can select pairs in any order.
+ */
+
+/**
+ * @param {number[][]} pairs
+ * @return {number}
+ */
+var findLongestChain = function(pairs) {
+  pairs.sort((a, b) => a[1] - b[1]);
+  let pointer = -Infinity;
+  let result = 0;
+
+  for (const [start, end] of pairs) {
+    if (start > pointer) {
+      pointer = end;
+      result++;
+    }
+  }
+
+  return result;
+};

README.md

@@ -485,6 +485,7 @@
 641|[Design Circular Deque](./0641-design-circular-deque.js)|Medium|
 643|[Maximum Average Subarray I](./0643-maximum-average-subarray-i.js)|Easy|
 645|[Set Mismatch](./0645-set-mismatch.js)|Medium|
+646|[Maximum Length of Pair Chain](./0646-maximum-length-of-pair-chain.js)|Medium|
 648|[Replace Words](./0648-replace-words.js)|Medium|
 649|[Dota2 Senate](./0649-dota2-senate.js)|Medium|
 653|[Two Sum IV - Input is a BST](./0653-two-sum-iv-input-is-a-bst.js)|Easy|