Minimum Impossible OR
You are given a 0-indexed integer array nums.
We say that an integer x is expressible from nums if there exist some integers 0 <= index1 < index2 < ... < indexk < nums.length for which nums[index1] | nums[index2] | ... | nums[indexk] = x. In other words, an integer is expressible if it can be written as the bitwise OR of some subsequence of nums.
Return the minimum positive non-zero integer that is not expressible from nums.
Example 1
Input
nums = [2,1]Output
41 and 2 are already present in the array, 3 is expressible as 2 | 1, and 4 is not expressible.
Example 2
Input
nums = [5,3,2]Output
11 is the smallest number that is not expressible.
Constraints
- 1 <= nums.length <= 10^5
- 1 <= nums[i] <= 10^9