/
xddxdd
/
Python
Обзор
Документация
Войти
/
xddxdd
/
Python
Код
Запросы
0
Задачи
Вики
Пакеты
0
Релизы
0
Аналитика
Безопасность
master
bit_manipulation/is_power_of_two.py
57 строк
1 KB
Alexander Pantyukhin
Is power of two (#7936)
01 ноя 2022, 20:43
Не верифицирован
01 ноя 2022, 20:43
4e6c1c0
Код
Авторство
О чём код?
""" 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 """ def 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 """ if number < 0: raise ValueError("number must not be negative") return number & (number - 1) == 0 if __name__ == "__main__": import doctest doctest.testmod()