Add solution #354

Author: JoshCrozier

README.md

@@ -283,6 +283,7 @@
 349|[Intersection of Two Arrays](./0349-intersection-of-two-arrays.js)|Easy|
 350|[Intersection of Two Arrays II](./0350-intersection-of-two-arrays-ii.js)|Easy|
 352|[Data Stream as Disjoint Intervals](./0352-data-stream-as-disjoint-intervals.js)|Hard|
+354|[Russian Doll Envelopes](./0354-russian-doll-envelopes.js)|Hard|
 355|[Design Twitter](./0355-design-twitter.js)|Medium|
 367|[Valid Perfect Square](./0367-valid-perfect-square.js)|Easy|
 371|[Sum of Two Integers](./0371-sum-of-two-integers.js)|Medium|

solutions/0354-russian-doll-envelopes.js

@@ -0,0 +1,44 @@
+/**
+ * 354. Russian Doll Envelopes
+ * https://leetcode.com/problems/russian-doll-envelopes/
+ * Difficulty: Hard
+ *
+ * You are given a 2D array of integers envelopes where envelopes[i] = [wi, hi] represents
+ * the width and the height of an envelope.
+ *
+ * One envelope can fit into another if and only if both the width and height of one envelope
+ * are greater than the other envelope's width and height.
+ *
+ * Return the maximum number of envelopes you can Russian doll (i.e., put one inside the other).
+ *
+ * Note: You cannot rotate an envelope.
+ */
+
+/**
+ * @param {number[][]} envelopes
+ * @return {number}
+ */
+var maxEnvelopes = function(envelopes) {
+  const result = [];
+
+  envelopes.sort((a, b) => a[0] === b[0] ? b[1] - a[1] : a[0] - b[0]);
+  envelopes.forEach(([_, h]) => {
+    let left = 0;
+    let right = result.length;
+    while (left < right) {
+      const middle = Math.floor((left + right) / 2);
+      if (result[middle] >= h) {
+        right = middle;
+      } else {
+        left = middle + 1;
+      }
+    }
+    if (left === result.length) {
+      result.push(h);
+    } else {
+      result[left] = h;
+    }
+  });
+
+  return result.length;
+};