326. Power of Three

Problem

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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

Solution

/**
 * @param {number} n
 * @return {boolean}
 */
var isPowerOfThree = function(n) {
  if (n <= 0) {
    return false;
  }
  if (n == 1) {
    return true;
  }

  let result = n;

  while (result > 3) {
    result /= 3;
  }

  if (result % 3 != 0) {
    return false;
  } else {
    return true;
  }
};