326. Power of Three

1. Question

Given an integer n, return true if it is a power of three. Otherwise, return false.

An integer n is a power of three, if there exists an integer x such that n == 3^x.

2. Examples

Example 1:

Input: n = 27
Output: true

Example 2:

Input: n = 0
Output: false

Example 3:

Input: n = 9
Output: true

Example 4:

Input: n = 45
Output: false

3. Constraints

• -2³¹ <= n <= 2³¹ - 1

4. References

来源：力扣（LeetCode） 链接：https://leetcode-cn.com/problems/power-of-three 著作权归领扣网络所有。商业转载请联系官方授权，非商业转载请注明出处。

5. Solutions

class Solution {
    public boolean isPowerOfThree(int n) {
        while (n > 0 && n % 3 == 0) {
            n /= 3;
        }
        return n == 1;
    }
}