326. Power of Three

1.描述

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?

2.分析

3.代码

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