a,b=map(int,input().split())
s=sorted([a,b])
s1=(s[0]**2+s[1]**2)**0.5
s2=(s[1]**2-s[0]**2)**0.5
if s2==0:
    s2=10000000000000000000000000000
print(round(min([s1,s2]),10))