Leetcode 231. Power of Two

class Solution {
public:
    bool isPowerOfTwo(int n) {
        if(n == 0) {
            return false;
        }
        while(n != 1) {
            if(n % 2) {
               return false; 
            }
            n /= 2;
        }
        return true;
    }
};

class Solution {
public:
    bool isPowerOfTwo(int n) {
        if(n == 0) {
            return false;
        }
        while(n != 1) {
            if(n % 2) {
               return false; 
            }
            n >>= 1;
        }
        return true;
    }
};

class Solution {
public:
    bool isPowerOfTwo(int n) {
        return n > 0 && !(n & (n - 1));
    }
};