Solution

Method 1 – Dynamic Programming with Sets

Intuition

The key idea is to keep track of all possible bitwise OR results for subarrays ending at each position. Since OR is monotonic (adding more elements can only set more bits), the number of unique results per step is manageable. By iteratively updating the set of ORs for each subarray ending at the current index, we can efficiently collect all unique OR values.

Approach

Initialize an empty set ans to store all unique OR results.
Initialize an empty set cur to store OR results for subarrays ending at the previous index.
For each element x in the array:

Create a new set nxt to store OR results for subarrays ending at the current index.
For each value y in cur, add

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