def get_1s_count(number: int) -> int:
"""
Count the number of set bits in a 32 bit integer using Brian Kernighan's way.
Ref - https://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetKernighan
>>> get_1s_count(25)
3
>>> get_1s_count(37)
3
>>> get_1s_count(21)
3
>>> get_1s_count(58)
4
>>> get_1s_count(0)
0
>>> get_1s_count(256)
1
>>> get_1s_count(-1)
Traceback (most recent call last):
...
ValueError: Input must be a non-negative integer
>>> get_1s_count(0.8)
Traceback (most recent call last):
...
ValueError: Input must be a non-negative integer
>>> get_1s_count("25")
Traceback (most recent call last):
...
ValueError: Input must be a non-negative integer
"""
if not isinstance(number, int) or number < 0:
raise ValueError("Input must be a non-negative integer")
count = 0
while number:
number &= number - 1
count += 1
return count
if __name__ == "__main__":
import doctest
doctest.testmod()