"""

Count Flips to Convert

Determine the minimal number of bits you would need to flip to convert

integer A to integer B. Uses XOR to find differing bits and Brian

Kernighan's algorithm to count them.

Reference: https://en.wikipedia.org/wiki/Hamming_distance

Complexity:

Time: O(k) where k is the number of differing bits

Space: O(1)

"""

from __future__ import annotations

def count_flips_to_convert(first: int, second: int) -> int:

"""Count the number of bit flips needed to convert one integer to another.

Args:

first: The source integer.

second: The target integer.

Returns:

The number of bits that differ between *first* and *second*.

Examples:

>>> count_flips_to_convert(29, 15)

2

>>> count_flips_to_convert(34, 34)

0

"""

diff = first ^ second

count = 0

while diff:

diff &= diff - 1

count += 1

return count