// Find All Numbers Disappeared in an Array — EASY

// Category: array

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`.

**Challenge:** Could you do it without extra space and in O(n) runtime?

Example: nums = [4,3,2,7,8,2,3,1]

Output: [5,6]