LeetCode in Kotlin

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

@Suppress("NAME_SHADOWING")
class Solution {
    fun isPowerOfFour(n: Int): Boolean {
        var n = n
        while (n >= 4) {
            if (n % 4 != 0) {
                return false
            }
            n = n / 4
        }
        return n == 1
    }
}

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