Python Elegant & Short | O(n) | Powers of two
\nfrom typing import List\n\n\nclass Solution:\n    """\n    Time:   O(n)\n    Memory: O(n)\n    """\n\n    def minImpossibleOR(self, nums: List[int]) -> int:\n
```\nfrom typing import List\n\n\nclass Solution:\n    """\n    Time:   O(n)\n    Memory: O(n)\n    """\n\n    def minImpossibleOR(self, nums: List[int]) -> int:\n        nums = set(nums)\n        impossible = 1\n\n        while impossible in nums:\n            impossible <<= 1\n\n        return impossible\n\n```
['Bit Manipulation', 'Python', 'Python3']