934 Bitwise Ors Of Subarrays

Bitwise ORs of Subarrays

Given an integer array arr, return the number of distinct bitwise ORs of all the non-empty subarrays of arr.

The bitwise OR of a subarray is the bitwise OR of each integer in the subarray. The bitwise OR of a subarray of one integer is that integer.

A subarray is a contiguous non-empty sequence of elements within an array.

 

Example 1:

**Input:** arr = [0]
**Output:** 1
**Explanation:** There is only one possible result: 0.

Example 2:

**Input:** arr = [1,1,2]
**Output:** 3
**Explanation:** The possible subarrays are [1], [1], [2], [1, 1], [1, 2], [1, 1, 2].
These yield the results 1, 1, 2, 1, 3, 3.
There are 3 unique values, so the answer is 3.

Example 3:

**Input:** arr = [1,2,4]
**Output:** 6
**Explanation:** The possible results are 1, 2, 3, 4, 6, and 7.

 

Constraints:

1 <= arr.length <= 5 * 104
0 <= arr[i] <= 109

class Solution(object):
    def subarrayBitwiseORs(self, A):
        ans = set()
        cur = {0}
        for x in A:
            cur = {x | y for y in cur} | {x}
            ans |= cur
        return len(ans)