import heapq

N = int(input())
A = list(map(int, input().split()))
B = list(map(lambda x: int(x) // 2, input().split()))

answer = N + 1
for start in range(N):
	que = [ (A[i], 0) for i in range(N) ]
	heapq.heapify(que)
	subanswer = 0
	for i in range(N):
		u = heapq.heappop(que)
		heapq.heappush(que, (u[0] + B[(start + i) % N], u[1] + 1))
		subanswer = max(subanswer, u[1] + 1)
	answer = min(answer, subanswer)

print(answer)