import math 
P,Q=map(int,input().split())
r=10**11;l=0
useadd=math.log(1.5,2)
use=math.log(r+l,2)-1
while r-l>10**-6:
    mid=(r+l)/2
    #use-=1
    if mid**2<P+Q*mid*use:
        use+=useadd
        l=mid 
    else:
        use-=1
        r=mid

print(l)