Longest Strictly Increasing Subsequence With Non-Zero Bitwise AND

Medium · binary search solution for Longest Strictly Increasing Subsequence With Non-Zero Bitwise AND. Python, Go, and a step-by-step animation.

Problem

Read the prompt, flip through the examples, then steal the idea.

LeetCode 3825. Longest Strictly Increasing Subsequence With Non-Zero Bitwise AND. The copyrighted prompt is on LeetCode. This page is a working binary search solution for this problem: editable input, Python, Go, and a step-by-step animation.

Constraints

—Player inputs are capped so the animation stays readable.
—Match LeetCode's own constraints when you submit there.

Examples

Input

nums =: [-1, 0, 3, 5, 9, 12]
target =: 9

Output

9 sits at index 4. Each step throws away half the range.

Solution

Python and Go. The walkthrough below runs this same code.

Approach 1Optimal▶ Animated

Longest Strictly Increasing Subsequence With Non-Zero Bitwise AND — binary search

Halve the sorted range until the target is found or the range collapses. Built for LeetCode 3825. Longest Strictly Increasing Subsequence With Non-Zero Bitwise AND.

Because the slice is sorted, comparing nums[mid] to target tells you which half can be thrown away. That is the whole algorithm.

Algorithm

While lo <= hi, pick mid.
Equal → return mid. Too small → search right. Too big → search left.
Empty range → not found (-1).

Time: O(log n)
Space: O(1)

Solution.py

1class Solution:2    def longestStrictlyIncreasingSubsequenceWithNonZeroBitwiseAnd(self, nums: list[int], target: int) -> int:3        lo, hi = 0, len(nums) - 14        while lo <= hi:5            mid = (lo + hi) // 26            if nums[mid] == target:7                return mid8            if nums[mid] < target:9                lo = mid + 110            else:11                hi = mid - 112        return -1

Watch this run

Interactive walkthrough

Playing “Longest Strictly Increasing Subsequence With Non-Zero Bitwise AND — binary search”. Edit the input, hit Run, then scrub.

Approach: Longest Strictly Increasing Subsequence With Non-Zero Bitwise AND — binary search

Loading animation…