a = int(input())
b = int(input())
while a != 0 and b != 0:
if a > b:
a %= b
else:
b %= a
gcd = a + b
print(gcd)# your code goes here
YSA9IGludChpbnB1dCgpKQpiID0gaW50KGlucHV0KCkpCgp3aGlsZSBhICE9IDAgYW5kIGIgIT0gMDoKICAgIGlmIGEgPiBiOgogICAgICAgIGEgJT0gYgogICAgZWxzZToKICAgICAgICBiICU9IGEKCmdjZCA9IGEgKyBiCnByaW50KGdjZCkjIHlvdXIgY29kZSBnb2VzIGhlcmU=