package main

import (
	"bufio"
	"fmt"
	"math/rand"
	"os"
	"strconv"
	"time"
)

var sc = bufio.NewScanner(os.Stdin)
var rdr = bufio.NewReaderSize(os.Stdin, 1000000)

func main() {
	sc.Split(bufio.ScanWords)
	n := nextInt()
	a, b := make([]int, n), make([]int, n)
	r := rand.New(rand.NewSource(time.Now().UnixNano()))
	for i := range a {
		a[i] = nextInt()
	}

	for i := range b {
		b[i] = nextInt()
	}

	newA, newB := make([]int, n), make([]int, n)
	wC := 0
	for i := 0; i < 50000; i++ {
		newA, newB := newA[:n], newB[:n]
		copy(newA, a)
		copy(newB, b)
		aWin, bWin := 0, 0
		for j := 0; j < n; j++ {
			aI, bI := r.Intn(len(newA)), r.Intn(len(newB))
			aH, bH := newA[aI], newB[bI]
			newA = append(newA[:aI], newA[aI+1:]...)
			newB = append(newB[:bI], newB[bI+1:]...)
			if aH > bH {
				aWin++
			} else if bH > aH {
				bWin++
			}
		}
		if aWin > bWin {
			wC++
		}
	}
	fmt.Println(float64(wC) / 50000)
}

func nextLine() string {
	sc.Scan()
	return sc.Text()
}

func nextInt() int {
	i, _ := strconv.Atoi(nextLine())
	return i
}