Add solution #665

Author: JoshCrozier

README.md

@@ -502,6 +502,7 @@
 661|[Image Smoother](./0661-image-smoother.js)|Easy|
 662|[Maximum Width of Binary Tree](./0662-maximum-width-of-binary-tree.js)|Medium|
 664|[Strange Printer](./0664-strange-printer.js)|Hard|
+665|[Non-decreasing Array](./0665-non-decreasing-array.js)|Medium|
 667|[Beautiful Arrangement II](./0667-beautiful-arrangement-ii.js)|Medium|
 668|[Kth Smallest Number in Multiplication Table](./0668-kth-smallest-number-in-multiplication-table.js)|Hard|
 669|[Trim a Binary Search Tree](./0669-trim-a-binary-search-tree.js)|Medium|

solutions/0665-non-decreasing-array.js

@@ -0,0 +1,33 @@
+/**
+ * 665. Non-decreasing Array
+ * https://leetcode.com/problems/non-decreasing-array/
+ * Difficulty: Medium
+ *
+ * Given an array nums with n integers, your task is to check if it could become non-decreasing
+ * by modifying at most one element.
+ *
+ * We define an array is non-decreasing if nums[i] <= nums[i + 1] holds for every i (0-based)
+ * such that (0 <= i <= n - 2).
+ */
+
+/**
+ * @param {number[]} nums
+ * @return {boolean}
+ */
+var checkPossibility = function(nums) {
+  let count = 0;
+
+  for (let i = 0; i < nums.length - 1; i++) {
+    if (nums[i] > nums[i + 1]) {
+      count++;
+      if (count > 1) return false;
+      if (i > 0 && nums[i - 1] > nums[i + 1]) {
+        nums[i + 1] = nums[i];
+      } else {
+        nums[i] = nums[i + 1];
+      }
+    }
+  }
+
+  return true;
+};