from heapq import heappush, heappop
import sys
input = sys.stdin.readline

N = int(input())
A = list(map(int, input().split()))
B = list(map(int, input().split()))
ans = float('inf')
for i in range(N):
    heap = []
    for j in range(N):
        heappush(heap, (A[j], 0))
    for j in range(N):
        level, cnt = heappop(heap)
        level += B[(i+j)%N] // 2
        cnt += 1
        heappush(heap, (level, cnt))
    ans = min(ans, max(cnt for val, cnt in heap))
print(ans)