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
Example 4:
Input: n = 45
Output: false
Constraints:
-2^31 <= n <= 2^31 - 1
Follow up: Could you do it without using any loop / recursion?
Solution in python:
class Solution:
def isPowerOfThree(self, n: int) -> bool:
if n <= 0:
return False
while n > 1:
if n%3 == 0:
n //= 3
continue
else:
return False
return True
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