30-seconds-of-code/snippets/gcd.md

gcd

Calculates the greatest common divisor between two or more numbers/arrays.

The helperGcdfunction uses recursion. Base case is when y equals 0. In this case, return x. Otherwise, return the GCD of y and the remainder of the division x/y.

Uses the reduce function from the inbuild module functools. Also defines a method spread for javascript like spreading of arrays.

from functools import reduce


def spread(arg):
    ret = []
    for i in arg:
        if isinstance(i, list):
            ret.extend(i)
        else:
            ret.append(i)
    return ret


def gcd(*args):
    numbers = []
    numbers.extend(spread(list(args)))

    def _gcd(x, y):
        return x if not y else gcd(y, x % y)

    return reduce((lambda x, y: _gcd(x, y)), numbers)

gcd(8,36) # 4