下次建议把更相减损术也带上

def gxzss(a,b):
    c=a-b
    if c==0:return a
    else:
        if c>b:
            return gxzss(c,b)
        else:
            return gxzss(b,c)
m,n=map(int,input().split())
if m<n:m,n=n,m
r2=0
while m%2==0 and n%2==0:
    r2+=1;m,n=m//2,n//2
print(2**r2*gxzss(m,n))