Bitwise Ors Of Subarrays - Leetcode Solution

Problem Statement

Given an integer array nums of size n and an integer k, return the bitwise OR of all possible subarrays of nums of size k.

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

Example:

Input: nums = [1,2,4], k = 2

Output: 7

Explanation: The subarrays of size 2 are [1,2] and [2,4]. The bitwise OR of these subarrays are 3 and 6 respectively. Therefore, the answer is 7.

Solution

The problem can be solved using a sliding window approach. Initialize a variable result with 0. Then, iterate over the array nums from index 0 to k - 1, and compute the bitwise OR of each subarray of size k. Add this result to the variable result.

After the k iterations, shift your window one element at a time to the right. At each iteration, remove the left-most element and add the new element. Compute the bitwise OR of the new subarray of size k and add it to the variable result.

After n - k + 1 iterations, return the final result.

Code implementation:

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