isPowerOfTwo

Checks if the given number is a power of 2.

• Use the bitwise binary AND operator (&) to determine if n is a power of 2.
• Additionally, check that n is not falsy.

const isPowerOfTwo = n => !!n && (n & (n - 1)) == 0;

isPowerOfTwo(0); // false
isPowerOfTwo(1); // true
isPowerOfTwo(8); // true