326. Power of Three

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Problem

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.

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

Code

class Solution {
    public boolean isPowerOfThree(int n) {
        if (n <= 0) return false;

        while (n % 3 == 0) {
            n /= 3;
        }

        return n == 1;
    }
}

class Solution {
    public boolean isPowerOfThree(int n) {
        return (Math.log10(n) / Math.log10(3)) % 1 == 0;
    }
}