package main

import (
	"bufio"
	"fmt"
	"math"
	"os"
	"strconv"
)

func main() {
	P := float64(readInt())
	Q := float64(readInt())

	ok := 1.0
	ng := 1e12
	for ng-ok > 1e-5 {
		N := ok + (ng-ok)/2
		if N*N <= Q*math.Log2(N)*N+P {
			ok = N
		} else {
			ng = N
		}
	}
	fmt.Println(ok)
}

const (
	ioBufferSize = 1 * 1024 * 1024 // 1 MB
)

var stdinScanner = func() *bufio.Scanner {
	result := bufio.NewScanner(os.Stdin)
	result.Buffer(make([]byte, ioBufferSize), ioBufferSize)
	result.Split(bufio.ScanWords)
	return result
}()

func readString() string {
	stdinScanner.Scan()
	return stdinScanner.Text()
}

func readInt() int {
	result, err := strconv.Atoi(readString())
	if err != nil {
		panic(err)
	}
	return result
}