import heapq

N = int(input())
parties = list(map(int, input().split()))
monsters = list(map(int, input().split()))
monsters = monsters + monsters

result = N

for i in range(N):
    k = i
    battles = [(x, 0) for x in parties]
    heapq.heapify(battles)
    for j in range(N):
        idx = battles[0]
        heapq.heappushpop(battles, (idx[0] + monsters[k] // 2, idx[1] + 1))
        k += 1
        if k >= N:
            k = 0
    maximum = 0
    for battle in battles:
        maximum = max(maximum, battle[1])
    result = min(result, maximum)

print(result)