import unittest

class Solution:

"""

This solution does a bitwise XOR between the two numbers to

create a number with the differing bits. Then the algorithm

keeps checking the rightmost bit while shifting the resulting

number to the right until the number eventually is equal to zero.

"""

def hammingDistance(self, x: int, y: int) -> int:

bits = 0

xor = x ^ y

while xor:

bits += xor & 1

xor = xor >> 1

return bits

class TestSolution(unittest.TestCase):

def test_first_example(self):

self.assertEqual(Solution().hammingDistance(1, 4), 2)