# -*- coding: utf-8 -*-

def SaidaiKoyaku (a,b):
    r = a % b
    if r == 0: return b
    return SaidaiKoyaku (b,r)

print("２つの数字を入力")
a=int(input("a="))
b=int(input("b="))

print("最大公約数",SaidaiKoyaku (a,b))