Leetcode Algorithms

231. Power of Two

Given an integer, write a function to determine if it is a power of two.

Example 1:

Input: 1
Output: true
Explanation: 20 = 1

Example 2:

Input: 16
Output: true
Explanation: 24 = 16

Example 3:

Input: 218
Output: false


Power of 2 means only 1 bit of n is 1. Hence, we can use bitwise operation: (n&(n-1)) == 1 to test if n is the power of 2


class Solution:
def isPowerOfTwo(self, n:int) -> bool:
if n <= 0:
return False
elif (n&(n - 1)) == 0:
return True





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