import heapq N = int(input()) A = list(map(lambda x: int(x) * 2000, input().split())) B = list(map(int, input().split())) ans = N for i in range(-N + 1, 1): a = A.copy() heapq.heapify(a) x = 0 for j in range(i, i + N): r = heapq.heappop(a) r += 1 + 2000 * (B[j] // 2) x = max(r % 2000, x) heapq.heappush(a, r) ans = min(ans, x) print(ans)