217. Find All Numbers Disappeared in an Array

Easy
Index Marking
Array

Problem

Given an integer array nums of length n where every value is between 1 and n, return all numbers in the range [1, n] that do not appear in nums.

Examples

Example 1

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

Example 2

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

Example 3

Input: [1,2,3]
Output: []
Constraints

1 <= nums.length <= 100000

1 <= nums[i] <= nums.length

Hints

?? Use each value as an index.

?? Mark visited indices using sign changes or cyclic placement.

Expected Complexity
Time: O(n)
Space: O(1) auxiliary
Follow-up

Can you solve it without an extra hash set?

Practice Notes

Attempts: 0

Time spent: 0min

Hints used: 0

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Case 1
Case 2
Case 3
Input
[4,3,2,7,8,2,3,1]
Expected
[5,6]