Add solution #448

Author: JoshCrozier

README.md

@@ -33,6 +33,7 @@
 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|
 387|[First Unique Character in a String](./0387-first-unique-character-in-a-string.js)|Easy|
+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|
 459|[Repeated Substring Pattern](./0459-repeated-substring-pattern.js)|Easy|
 541|[Reverse String II](./0541-reverse-string-ii.js)|Easy|

solutions/0448-find-all-numbers-disappeared-in-an-array.js

@@ -0,0 +1,33 @@
+/**
+ * 448. Find All Numbers Disappeared in an Array
+ * https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/
+ * Difficulty: Easy
+ *
+ * Given an array `nums` of `n` integers where `nums[i]` is in the
+ * range `[1, n]`, return an array of all the integers in the
+ * range `[1, n]` that do not appear in nums.
+ */
+
+/**
+ * @param {number[]} nums
+ * @return {number[]}
+ */
+var findDisappearedNumbers = function(nums) {
+  const result = [];
+
+  for (let i = 0; i < nums.length;) {
+    if (nums[nums[i] - 1] !== nums[i]) {
+      [nums[nums[i] - 1], nums[i]] = [nums[i], nums[nums[i] - 1]];
+    } else {
+      i++;
+    }
+  }
+
+  nums.forEach((v, i) => {
+    if (v != i + 1) {
+      result.push(i + 1);
+    }
+  });
+
+  return result;
+};