diff --git a/maths/modular_division.py b/maths/modular_division.py index 94f12b3e096e..ed4ae6ae8ce3 100644 --- a/maths/modular_division.py +++ b/maths/modular_division.py @@ -28,9 +28,13 @@ def modular_division(a: int, b: int, n: int) -> int: 4 """ - assert n > 1 - assert a > 0 - assert greatest_common_divisor(a, n) == 1 + if n <= 1: + raise ValueError("Modulus n must be greater than 1") + if a <= 0: + raise ValueError("Divisor a must be a positive integer") + if greatest_common_divisor(a, n) != 1: + raise ValueError("a and n must be coprime (gcd(a, n) = 1)") + (_d, _t, s) = extended_gcd(n, a) # Implemented below x = (b * s) % n return x