方法一

import math

nums = input()
nums = nums.split(' ')
print(math.gcd(int(nums[0]), int(nums[1])))

方法二

def gcd(x, y):
    while y:
        x, y = y, x % y
    return x

nums = input()
nums = nums.split(' ')
print(gcd(int(nums[0]), int(nums[1])))