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Find All Numbers Disappeared in an Array

Problem statement​

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.

Example 1:

Input: nums = [4,3,2,7,8,2,3,1]Output: [5,6]

Example 2:

Input: nums = [1,1]Output: [2]

Constraints:

  • n == nums.length
  • 1 <= n <= 105
  • 1 <= nums[i] <= n

Follow up: Could you do it without extra space and in O(n) runtime? You may assume the returned list does not count as extra space.

My solution​

/**
 * @param {number[]} nums
 * @return {number[]}
 */
var findDisappearedNumbers = function(nums) {
  const newNums = Array.from(new Array(nums.length)).fill(false);
    for (const num of nums) {
        newNums[num - 1] = true
    }
    // console.log(newNums);
    return newNums.map((v, i) => v === false && i + 1).filter(v => v)
};