Walter Teng.342 Power of Four - Easy
Problem:
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?
Problem Analysis:
- use bitwise manipulation or log formula
Solutions:
class Solution:
def isPowerOfFour(self, n: int) -> bool:
return n>0 and log(n,4) %1 == 0
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