188. Power of Two

Easy · Bit Manipulation

Given an integer n, determine whether it is a power of two. A power of two is a number that can be expressed as 2^k where k is a non-negative integer.

For example, 1, 2, 4, 8, 16 are powers of two. Numbers like 3, 5, 6, 7 are not powers of two.

Examples

Example 1
Input: 8
Output: true
Explanation: 8 = 2^3, so it is a power of two.
Example 2
Input: 5
Output: false
Explanation: 5 cannot be expressed as 2^k for any non-negative integer k.

Constraints