LeetCode 326. Power of Three

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

class Solution(object):
    #120ms, 11.8MB
    def isPowerOfThree(self, n):
        """
        :type n: int
        :rtype: bool
        """
        if n <= 0: return False
        if n == 1: return True
        else:
            while n % 3 == 0:
                n = n//3
                if n == 1: return True
            return False