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;
        }
    }
};