O(n) time and space Simple set solution
Complexity

Time complexity:O(n)


Space complexity:O(n)

Code
# Complexity
- Time complexity: $$O(n)$$

- Space complexity: $$O(n)$$

# Code
```python3 []
class Solution:
    def minImpossibleOR(self, nums: List[int]) -> int:
        nums = set(nums)
        power = 0

        while pow(2, power) in nums:
            power += 1
        
        return pow(2, power)
```
['Array', 'Bit Manipulation', 'Brainteaser', 'Python3']