is_power_of_two.py

"""
Author  : Alexander Pantyukhin
Date    : November 1, 2022

Task:
Given a positive int number. Return True if this number is power of 2
and False otherwise.

Implementation notes: Use bit manipulation.
For example if the number is the power of two it's bits representation:
n     = 0..100..00
n - 1 = 0..011..11

n & (n - 1) - no intersections = 0

"""


def is_power_of_two(number: int) -> bool:
    """
    >>> is_power_of_two(2)
    True
    >>> is_power_of_two(4)
    True
    >>> is_power_of_two(6)
    False
    >>> is_power_of_two(8)
    True
    >>> is_power_of_two(17)
    False
    >>> is_power_of_two(32)
    True
    >>> is_power_of_two(31)
    False
    """

    return number & (number - 1) == 0


if __name__ == "__main__":
    import doctest

    doctest.testmod()