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.
Constraints
-231 <= n <= 231 - 1
Approach
Links
GeeksforGeeks
YouTube
Examples
Input: n = 27
Output: true
Input: n = 0
Output: false
Input: n = 9
Output: true
Input: n = 45
Output: false
Input: n = 1
Output: true
Solutions
/**
* Time complexity : O(log3(N)). The number of divisions is given by
* that logarithm.
* Space complexity : O(1). We are not using any additional memory.
*/
class Solution {
public boolean isPowerOfThree(int n) {
if(n == 0) {
return false;
}
while(n % 3 == 0) {
n /= 3;
}
return n == 1;
}
}