N=int(input())
A=list(map(int, input().split()))
B=list(map(int, input().split()))
A=sorted(A)[::-1]
B=sorted(B)
ma=0
for i in range(N):
  ma+=max(A[i]-B[i],0)
import itertools
D=list(itertools.permutations(range(N)))
ans=0
for i in D:
  cnt=0
  for j in range(N):
    cnt+=max(A[i[j]]-B[j],0)
  if cnt==ma:
    ans+=1
print(ans)