Practice/Meta/Leetcode 231. Power of Two

Leetcode 231. Power of Two

CodingOptional

Problem

Write a function that determines whether a given integer is a power of two. An integer is considered a power of two if it can be expressed as 2 raised to some non-negative integer exponent (2^x where x >= 0).

Your function should return true if the number is a power of two, and false otherwise.

Requirements

1. The function must handle any 32-bit signed integer
2. Return false for zero and negative numbers
3. The solution should be efficient and avoid using loops if possible

Constraints

• -2^31 ≤= n ≤= 2^31 - 1
• Aim for O(1) time complexity
• O(1) space complexity

Examples

Example 1:

Input: n = 16 Output: true Explanation: 16 equals 2^4

Example 2:

Input: n = 3 Output: false Explanation: 3 cannot be expressed as 2^x for any integer x

Example 3:

Input: n = 1 Output: true Explanation: 1 equals 2^0

Example 4:

Input: n = -8 Output: false Explanation: Negative numbers cannot be powers of two