Ezvor

3702. Longest Subsequence With Non-Zero Bitwise XOR

MediumArray Preparing judge… LeetCode

You are given an integer array nums.

Return the length of the longest subsequence in nums whose bitwise XOR is non-zero. If no such subsequence exists, return 0.

 

Example 1:

Input: nums = [1,2,3]

Output: 2

Explanation:

One longest subsequence is [2, 3]. The bitwise XOR is computed as 2 XOR 3 = 1, which is non-zero.

Example 2:

Input: nums = [2,3,4]

Output: 3

Explanation:

The longest subsequence is [2, 3, 4]. The bitwise XOR is computed as 2 XOR 3 XOR 4 = 5, which is non-zero.

 

Constraints:

  • 1 <= nums.length <= 105
  • 0 <= nums[i] <= 109
ArrayBit Manipulation

Hints

Hint 1
What happens if you take the entire array?
Hint 2
If the XOR of the entire array is 0, can removing one element help?
Hint 3
What if all elements are 0?