Python/bit_manipulation/is_even.py
2023-11-25 12:25:46 +01:00

38 lines
834 B
Python

def is_even(number: int) -> bool:
"""
return true if the input integer is even
Explanation: Lets take a look at the following decimal to binary conversions
2 => 10
14 => 1110
100 => 1100100
3 => 11
13 => 1101
101 => 1100101
from the above examples we can observe that
for all the odd integers there is always 1 set bit at the end
also, 1 in binary can be represented as 001, 00001, or 0000001
so for any odd integer n => n&1 is always equals 1 else the integer is even
>>> is_even(1)
False
>>> is_even(4)
True
>>> is_even(9)
False
>>> is_even(15)
False
>>> is_even(40)
True
>>> is_even(100)
True
>>> is_even(101)
False
"""
return number & 1 == 0
if __name__ == "__main__":
import doctest
doctest.testmod()