326. Power Of Three¶

LeetCode Problem View on GitHub

326. Power of Three

Easy

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
Explanation: 27 = 33

Example 2:

Input: n = 0
Output: false
Explanation: There is no x where 3x = 0.

Example 3:

Input: n = -1
Output: false
Explanation: There is no x where 3x = (-1).

Constraints:

• -231 <= n <= 231 - 1

Follow up: Could you solve it without loops/recursion?

Solution¶

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

Complexity Analysis¶

• Time Complexity: O(?)
• Space Complexity: O(?)

Approach¶

Detailed explanation of the approach will be added here