#41261: 為甚麼是TLE(可以教一下嗎)


suyueh (suyueh)


s=0
a,b=map(int,input().split())
if a>b:
  a,b=b,a
for i in range(1,a+1):
  if a%i==0 and b%i==0:
    s=i
print(s)