euclidian_gcd

# uses python3
import sys


def gcd_naive(n, p):
    current_gcd = 1
    for d in range(2, min(n, p) + 1):
        if n % d == 0 and p % d == 0:
            if d > current_gcd:
                current_gcd = d

    return current_gcd


def gcd_euclid(n, p):
    gcd = 1
    # if n < 0 or p < 0:
    #     gcd = 0
    # elif n + p == 0:
    #     gcd = 0

# From Chromium's style guide: Don't use else after return
    if p == 0:
        gcd = n
        return print(gcd)
    gcd_euclid(p, n % p)

# one liner cleaner?
def gcd_one_liner(n, p):
    gcd = n if p == 0 else gcd_one_liner(p, n % p)
    return gcd

if __name__ == "__main__":
    user_input = sys.stdin.read()
    a, b = map(int, user_input.split())
    # gcd_euclid(a, b)
    print(gcd_one_liner(a, b))