Find All Numbers Disappeared in an Array — Java Coding Problem
Difficulty: easy | Category: array
Problem Description
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?
Examples
Example 1
Input: nums = [4,3,2,7,8,2,3,1]
Output: [5,6]
Example 2
Input: nums = [1,1]
Output: [2]