EasyNo. 0868

Binary Gap — LeetCode 868 Python Solution

Topics
Bit Manipulation
Reading time
2 min

The problem

Given a positive integer n, find and return the longest distance between any two adjacent 1's in the binary representation of n. If there are no two adjacent 1's, return 0.

Example

Input
n = 22
Output
2
Explanation
22 in binary is "10110".

Python solution

PythonSolution
class Solution:
    def binaryGap(self, n: int) -> int:
        ans = 0
        pre, cur = inf, 0
        while n:
            if n & 1:
                ans = max(ans, cur - pre)
                pre = cur
            cur += 1
            n >>= 1
        return ans

Complexity

Time
O(log n)where n is the given integer
Space · auxiliary
O(1)

Pattern: Bit Manipulation

Use XOR, masks and the low-bit trick to replace whole data structures with an integer. LeetCode 868. Binary Gap is filed here on both counts: the reference solution below belongs to the algorithm family this hub collects, and LeetCode tags it Bit Manipulation.

The bit manipulation guide has the Python template for the pattern and the 194 LeetCode problems that use it.

Related problems

Related problems
No.ProblemDifficulty
0029Divide Two IntegersMedium
0067Add BinaryEasy
0136Single NumberEasy
0137Single Number IIMedium
0190Reverse BitsEasy
0191Number of 1 BitsEasy

Frequently asked questions

How hard is LeetCode 868. Binary Gap?

LeetCode 868. Binary Gap is rated Easy on LeetCode.

What is the time complexity of LeetCode 868. Binary Gap?

The Python solution on this page runs in O(log n), where n is the given integer.

What is the space complexity of LeetCode 868. Binary Gap?

The Python solution on this page uses O(1) auxiliary space.

What topics does LeetCode 868. Binary Gap cover?

LeetCode 868. Binary Gap is tagged Bit Manipulation on LeetCode.

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