from math import log2

def f(n):
    return n * n - P - Q * n * log2(n)

P, Q = map(int, input().split())
yes = 1
no = 10 ** 18
while no - yes > 10**-5:
    mid = (yes + no)/2
    if f(mid) <= 0:
        yes = mid
    else:
        no = mid
print(yes)