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?

class Solution {public:    bool isPowerOfThree(int n) {        if(n <=0 || n==2) return false;        if(n==1 || n==3) return true;        while(n>3){            if(n%3) return false;            n = n / 3;            if(n==3)                return true;            if(n==2)                return false;        }    }};