import itertools

N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
A.sort(reverse=True)
B.sort()
MAX = 0
for i in range(N):
  temp = max(A[i] - B[i],0)
  MAX += temp
ans = 0

L = list(itertools.permutations(A,N))
for X in L:
  point = 0
  for i in range(N):
    temp = max(X[i] - B[i],0)
    point += temp
  if point == MAX:
    ans += 1
print(ans)