import math
p, q = map(int,input().split())
l = 1
r = int(1e11)
while r-l > 1/int(1e5):
    m = (l+r) / 2
    f = p + q*m*math.log2(m)
    if m**2 >= f:
        r = m
    else:
        l = m
print(l)