Power of Three

Given an integer n, return true if it is a power of three. Otherwise, return false.

An integer n is a power of three, if there exists an integer x such that n == 3x.

 

Example 1:

Input: n = 27
Output: true

Example 2:

Input: n = 0
Output: false

Example 3:

Input: n = 9
Output: true

 

Constraints:

  • -231 <= n <= 231 - 1

 

Follow up: Could you solve it without loops/recursion?SOLUTION:
class Solution:
    def isPowerOfThree(self, n: int) -> bool:
        if n <= 0:
            return False
        while n % 3 == 0:
            n = n // 3
        return n == 1

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