Check if Number is a Sum of Powers of Three

Given an integer n, return true if it is possible to represent n as the sum of distinct powers of three. Otherwise, return false.

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

Example 1:

Input: n = 12
Output: true
Explanation: 12 = 31 + 32

Example 2:

Input: n = 91
Output: true
Explanation: 91 = 30 + 32 + 34

Example 3:

Input: n = 21
Output: false

Constraints:

• 1 <= n <= 107

SOLUTION:

class Solution:
    def checkPowersOfThree(self, n: int) -> bool:
        while n != 1:
            if n % 3 == 0:
                n = n // 3
            elif n % 3 == 1:
                n = (n - 1) // 3
            else:
                break
        return n == 1