import math

EPS = 1e-6

p, q = map(int, input().split())

ok = 1.0
ng = 8.0e10
while abs(ok - ng) > EPS:
  mid = (ok + ng) / 2

  if mid * mid <= p + q * mid * math.log(mid, 2):
    ok = mid
  else:
    ng = mid

print(ok)