898 - Bitwise ORs of Subarrays.

Medium

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:

• <code>1 <= arr.length <= 5 * 10⁴</code>

• <code>0 <= arri<= 10⁹</code>