448. Find All Numbers Disappeared in an Array

https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array

Python

class Solution:
    def findDisappearedNumbers(self, nums: List[int]) -> List[int]:
        n = len(nums)
        result = set(range(1, n+1))

        for num in nums:
            try:
                result.remove(num)
            except KeyError as err:
                pass

        return result