func main()
	var p: int :: cui@inputInt()
	var q: int :: cui@inputInt()
	
	var ok: float :: 1.0
	var ng: float :: (10 ^ 15) $ float
	for i(1, 200)
		var mid: float :: (ok + ng) / 2.0
		if(mid * mid <= p $ float + q $ float * mid * lib@log(2.0, mid))
			do ok :: mid
		else
			do ng :: mid
		end if
	end for
	var ans: float :: ok
	do cui@print("\{ans.toStrFmt(".9f")}\n")
end func