[LeetCode] 231. Power of Two

Given an integer, write a function to determine if it is a power of two.

 Thought process:

 If the number is not positive, return false directly. Divide the number by 2 until it becomes an odd number. If it's not 1, return false. Otherwise, return true.

 Solution:

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

Time complexity: O(logn).
Location: Philadelphia, PA, USA

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