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Power of Four

Tags : leetcode, bit-manipulation, recursion, cpp, easy

Problem Statement - link #

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 == 4^x.

Examples #

Example 1:

Input: n = 16
Output: true

Example 2:

Input: n = 5
Output: false

Example 3:

Input: n = 1
Output: true

Constraints #

Solutions #

class Solution {
public:
    bool isPowerOfFour(int n) {
        if(!n) return false;
        while(1){
           if(n==1||n==4) return true;
           if(n%4!=0) return false;
           n/=4;
        } 
        return true;
    }
};