Finding GCD.py

import math

def GCD(a , b):
    if(b == 0):
    	return a
    return GCD(b, a - math.floor(a/b)*b)

# Input values here and run
print(GCD(9876, 54321))


def bea(a,b):                       # "bea" = "backwards Euclidean Algorithm"
    if b == 0:
        return [1,0]
    else:
        x, y = bea(b, a % b)
        return [y, x - a//b * y]    # "//" operator is floor (i.e. rounding down)

print(bea(12345,67890))
# Will return solution [x, y]
# in the form of ax + by = gcd(a,b)