2419. Longest Subarray With Maximum Bitwise AND

Description

You are given an integer array nums of size n.

Consider a non-empty subarray from nums that has the maximum possible bitwise AND.

In other words, let k be the maximum value of the bitwise AND of any subarray of nums. Then, only subarrays with a bitwise AND equal to k should be considered.

Return the length of the longest such subarray.

The bitwise AND of an array is the bitwise AND of all the numbers in it.

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

Example 1:

Input: nums = [1,2,3,3,2,2]
Output: 2
Explanation:
The maximum possible bitwise AND of a subarray is 3.
The longest subarray with that value is [3,3], so we return 2.

Example 2:

Input: nums = [1,2,3,4]
Output: 1
Explanation:
The maximum possible bitwise AND of a subarray is 4.
The longest subarray with that value is [4], so we return 1.

Constraints:

1 <= nums.length <= 10⁵
1 <= nums[i] <= 10⁶

Solution

longest-subarray-with-maximum-bitwise-and.py

class Solution:
    def longestSubarray(self, nums: List[int]) -> int:
        N = len(nums)
        mmax = max(nums)
        curr = res = 0

        for x in nums:
            if x == mmax:
                curr += 1
            else:
                curr = 0

            res = max(res, curr)

        return res