from math import log2


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


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

for i in range(10 ** 6):
    t = ok + i / (10 ** 6)
    if not is_ok(t):
        break

print(ok + (i - 1) / (10 ** 6))