import math
p, q = map(int, input().split())
l = 0
r = 10**18

def f(x):
    if x**2 < p+q*x*math.log2(x):
        return True
    else:
        return False

while r-l > 0.00001:
    mid = (l+r)/2
    if f(mid):
        l = mid
    else:
        r = mid

print(l)