LeetCode(Math)Power of Three

Power of Three

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

Example 1:

Input: 27
Output: true

Example 2:

Input: 0
Output: false

Example 3:

Input: 9
Output: true

Example 4:

Input: 45
Output: false

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

思路：首先能想到的肯定是循环或者递归。代码如下：

class Solution {
    public boolean isPowerOfThree(int n) {
        if(n==0){
            return false;
        }
        while(n%3==0){
            n=n/3;
        }
        if(n==1){
            return true;
        }else{
            return false;
        }
    }
}