LeetCode-in-Java
342. Power of Four
Easy
Given an integer n, return true if it is a power of four. Otherwise, return false.
An integer n is a power of four, if there exists an integer x such that n == 4x.
Example 1:
Input: n = 16
Output: true
Example 2:
Input: n = 5
Output: false
Example 3:
Input: n = 1
Output: true
Constraints:
-231 <= n <= 231 - 1
Follow up: Could you solve it without loops/recursion?
Solution
public class Solution {
public boolean isPowerOfFour(int n) {
while (n >= 4) {
if (n % 4 != 0) {
return false;
}
n = n / 4;
}
return n == 1;
}
}