import math
P,Q = map(int,input().split())
maxt = 10**9
Nd = 10**18
dt = maxt/Nd
def is_ok(arg): 
    N = arg*dt
    return N**2 <= P + Q*N*math.log2(N)
def meguru_bisect(ng, ok):
    while (abs(ok - ng) > 1):
        mid = (ok + ng) // 2
        if is_ok(mid):
            ok = mid
        else:
            ng = mid
    return ok
ans  = meguru_bisect(10**30,0)*dt
print(ans)