Add solution #3105

Author: JoshCrozier

README.md

@@ -544,6 +544,7 @@
 2727|[Is Object Empty](./2727-is-object-empty.js)|Easy|
 2948|[Make Lexicographically Smallest Array by Swapping Elements](./2948-make-lexicographically-smallest-array-by-swapping-elements.js)|Medium|
 3042|[Count Prefix and Suffix Pairs I](./3042-count-prefix-and-suffix-pairs-i.js)|Easy|
+3105|[Longest Strictly Increasing or Strictly Decreasing Subarray](./3105-longest-strictly-increasing-or-strictly-decreasing-subarray.js)|Easy|
 3110|[Score of a String](./3110-score-of-a-string.js)|Easy|
 3151|[Special Array I](./3151-special-array-i.js)|Easy|
 3223|[Minimum Length of String After Operations](./3223-minimum-length-of-string-after-operations.js)|Medium|

solutions/3105-longest-strictly-increasing-or-strictly-decreasing-subarray.js

@@ -0,0 +1,22 @@
+/**
+ * 3105. Longest Strictly Increasing or Strictly Decreasing Subarray
+ * https://leetcode.com/problems/longest-strictly-increasing-or-strictly-decreasing-subarray/
+ * Difficulty: Easy
+ *
+ * You are given an array of integers nums. Return the length of the longest subarray of nums
+ * which is either strictly increasing or strictly decreasing.
+ */
+
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var longestMonotonicSubarray = function(nums) {
+  let result = nums.length > 0 ? 1 : 0;
+  for (let i = 1, down = 1, up = 1; i < nums.length; i++) {
+    nums[i - 1] > nums[i] ? down++ : down = 1;
+    nums[i - 1] < nums[i] ? up++ : up = 1;
+    result = Math.max(result, down, up);
+  }
+  return result;
+};