Add solution #456

Author: JoshCrozier

0456-132-pattern.js

@@ -0,0 +1,30 @@
+/**
+ * 456. 132 Pattern
+ * https://leetcode.com/problems/132-pattern/
+ * Difficulty: Medium
+ *
+ * Given an array of n integers nums, a 132 pattern is a subsequence of three integers nums[i],
+ * nums[j] and nums[k] such that i < j < k and nums[i] < nums[k] < nums[j].
+ *
+ * Return true if there is a 132 pattern in nums, otherwise, return false.
+ */
+
+/**
+ * @param {number[]} nums
+ * @return {boolean}
+ */
+var find132pattern = function(nums) {
+  const stack = [];
+
+  for (let i = nums.length - 1, j = -Infinity; i >= 0; i--) {
+    while (nums[i] > stack[stack.length - 1]) {
+      j = stack.pop();
+    }
+    if (nums[i] < j) {
+      return true;
+    }
+    stack.push(nums[i]);
+  }
+
+  return false;
+};

README.md

@@ -208,6 +208,7 @@
 448|[Find All Numbers Disappeared in an Array](./0448-find-all-numbers-disappeared-in-an-array.js)|Easy|
 451|[Sort Characters By Frequency](./0451-sort-characters-by-frequency.js)|Medium|
 452|[Minimum Number of Arrows to Burst Balloons](./0452-minimum-number-of-arrows-to-burst-balloons.js)|Medium|
+456|[132 Pattern](./0456-132-pattern.js)|Medium|
 459|[Repeated Substring Pattern](./0459-repeated-substring-pattern.js)|Easy|
 461|[Hamming Distance](./0461-hamming-distance.js)|Easy|
 463|[Island Perimeter](./0463-island-perimeter.js)|Medium|