All problems

Power of Two

Easy · bit manipulation

A number is a power of two if it equals 2 multiplied by itself some whole number of times, including zero times. So 1, 2, 4, 8, 16, ... are powers of two, and 0, negative numbers and numbers such as 6 are not.

Given an integer n, return true if n is a power of two and false otherwise.

Examples

Example 1

Input: n = 16

Output: True

16 = 2 * 2 * 2 * 2.

Example 2

Input: n = 12

Output: False

12 lies between 8 and 16, and is not equal to either.

Example 3

Input: n = -8

Output: False

Powers of two are positive, so a negative number never qualifies.

Constraints