leetcode-326-Power of Three

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

Follow up:
Could you do it without using any loop / recursion?

Credits:
Special thanks to @dietpepsi for adding this problem and creating all test cases.

Subscribe to see which companies asked this question

判断一个数是否为3的次方

C++

class Solution {public:    bool isPowerOfThree(int n) {        if ( !n ) return false ;        while ( n != 1 ) {            if ( n % 3 ) return false ;            else n = n / 3 ;        }        return true ;    }};

python

class Solution(object):    def isPowerOfThree(self, n):        """        :type n: int        :rtype: bool        """        if n == 0 :            return False        while n != 1 :            if ( n % 3 != 0 ) : return False            else : n = n / 3 ;                    return True