bit_manipulation.is_power_of_two

Author : Alexander Pantyukhin Date : November 1, 2022

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

Functions

is_power_of_two(→ bool)

Return True if this number is power of 2 or False otherwise.

Module Contents

bit_manipulation.is_power_of_two.is_power_of_two(number: int) → bool

Return True if this number is power of 2 or False otherwise.

>>> is_power_of_two(0)
True
>>> is_power_of_two(1)
True
>>> 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(-1)
Traceback (most recent call last):
    ...
ValueError: number must not be negative
>>> is_power_of_two(1.2)
Traceback (most recent call last):
    ...
TypeError: unsupported operand type(s) for &: 'float' and 'float'

# Test all powers of 2 from 0 to 10,000 >>> all(is_power_of_two(int(2 ** i)) for i in range(10000)) True