Introduction

In this blog post, we will explore how to solve the LeetCode problem "326" using AI. LeetCode is a popular platform for preparing for coding interviews, and with the help of AI tools like Chatmagic, we can generate solutions quickly and efficiently - helping you pass the interviews and get the job offer without having to study for months.

Problem Statement

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?

Explanation

Here's the breakdown of the approach, complexities, and the Python code:

• Approach:

  • Handle edge cases: n <= 0. Powers of 3 are always positive.
  • Find the largest power of 3 that fits within the integer range.
  • Check if the largest power of 3 is divisible by n. If it is, then n is a power of 3.

• Complexity:

  • Runtime: O(1), Storage: O(1)

Code

    class Solution:
    def isPowerOfThree(self, n: int) -> bool:
        if n <= 0:
            return False

        max_power_of_3 = 3**19  # Largest power of 3 within the 32-bit integer range
        return max_power_of_3 % n == 0