import streams, deques, sequtils, strutils, algorithm, math, future, sets, tables, hashes
proc `ceilDiv`*[T](x, y: T): T = x div y + ord(x mod y != 0)
proc `//=`*(x: var SomeInteger; y: SomeInteger) = x = x div y
proc `%=`*(x: var SomeInteger; y: SomeInteger) = x = x mod y


var
    L = stdin.readLine.split.map(parseFloat)
    P = L[0]
    Q = L[1]
    ldx = 0.0.float64
    rdx = float(10^12).float64
    mid = ((rdx + ldx) / 2).float64
while rdx - ldx > 0.00001:
    mid = (rdx + ldx) / 2
    if mid^2 <= Q * mid * log2(mid) + P:
        ldx = mid
    elif mid^2 > Q * mid * log2(mid) + P:
        rdx = mid
    # echo mid
echo mid