from math import log2

def gutyoku(n):
    return n ** 2 < Q * n * log2(n) + P
    

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

b, a = 1, 10 ** 18
while True:
    if a - b < 10 ** -7:
        break
    tmp = (a + b) / 2
    if gutyoku(tmp):
        b = tmp
    else:
        a = tmp    

print(a)