231. Power of Two.js

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

Example 1:

Input: 1
Output: true 
Explanation: 20 = 1
Example 2:

Input: 16
Output: true
Explanation: 24 = 16
Example 3:

Input: 218
Output: false
 */
/**
 * Algorithm: Bit manipulation
 * If a number n is a power of two: n & (n-1) == 0
 */
/**
 * @param {number} n
 * @return {boolean}
 */
var isPowerOfTwo = function(n) {
  return n > 0 && ((n & (n-1)) === 0);
};