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 == 3x.
\n
Example 1:
\n\n\nInput: n = 27\nOutput: true\n\n\n
Example 2:
\n\n\nInput: n = 0\nOutput: false\n\n\n
Example 3:
\n\n\nInput: n = 9\nOutput: true\n\n\n
\n
Constraints:
\n\n-231 <= n <= 231 - 1\nFollow up: Could you solve it without loops/recursion?", "translatedTitle": "3 的幂", "translatedContent": "
给定一个整数，写一个函数来判断它是否是 3 的幂次方。如果是，返回 true ；否则，返回 false 。
整数 n 是 3 的幂次方需满足：存在整数 x 使得 n == 3x
\n\n
示例 1：
\n\n\n输入：n = 27\n输出：true\n\n\n
示例 2：
\n\n\n输入：n = 0\n输出：false\n\n\n
示例 3：
\n\n\n输入：n = 9\n输出：true\n\n\n
示例 4：
\n\n\n输入：n = 45\n输出：false\n\n\n
\n\n
提示：
\n\n-231 <= n <= 231 - 1\n\n
进阶：你能不使用循环或者递归来完成本题吗？
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