Python/ciphers/cryptomath_module.py
Siddik Patel 583a614fef
Removed redundant greatest_common_divisor code ()
* Deleted greatest_common_divisor def from many files and instead imported the method from Maths folder

* Deleted greatest_common_divisor def from many files and instead imported the method from Maths folder, also fixed comments

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Deleted greatest_common_divisor def from many files and instead imported the method from Maths folder, also fixed comments

* Imports organized

* recursive gcd function implementation rolledback

* more gcd duplicates removed

* more gcd duplicates removed

* Update maths/carmichael_number.py

* updated files

* moved a file to another location

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Tianyi Zheng <tianyizheng02@gmail.com>
2023-10-09 14:19:12 +02:00

14 lines
432 B
Python

from maths.greatest_common_divisor import gcd_by_iterative
def find_mod_inverse(a: int, m: int) -> int:
if gcd_by_iterative(a, m) != 1:
msg = f"mod inverse of {a!r} and {m!r} does not exist"
raise ValueError(msg)
u1, u2, u3 = 1, 0, a
v1, v2, v3 = 0, 1, m
while v3 != 0:
q = u3 // v3
v1, v2, v3, u1, u2, u3 = (u1 - q * v1), (u2 - q * v2), (u3 - q * v3), v1, v2, v3
return u1 % m