from math import log2


def is_ok(N):
    return N <= Q * log2(N) + P / N


P, Q = map(int, input().split())

ok = 1
ng = 10 ** 18
while ng - ok > 1:
    m = (ok + ng) // 2
    if is_ok(m):
        ok = m
    else:
        ng = m

t = ok
e = 1 / 2 ** 18
while is_ok(t):
    t += e

print(t - e)