import strutils, sequtils, algorithm

let N = stdin.readline.parseInt

var
    A = stdin.readLine.split.map(parseInt).sorted()
    B = stdin.readLine.split.map(parseInt).sorted()
    aPerm = newSeq[seq[int]]()
    bPerm = newSeq[seq[int]]()
    cnt = 0
    general_aWin = 0

while true:
    aPerm.add(A)
    if A.nextPermutation() == false: break

while true:
    bPerm.add(B)
    if B.nextPermutation() == false: break

for a in aPerm:
    for b in bPerm:
        inc cnt
        var
            aWin = 0
            bWin = 0
        for i in 0..<N:
            if a[i] > b[i]:
                inc aWin
            else:
                inc bWin

        if aWin > bWin:
            inc general_aWin


echo general_aWin/cnt