from heapq import heappush, heappop, heapify

n = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
B = [b//2 for b in B]
B += B
ans = 10**10
base = [(a,0) for a in A]
heapify(base)
for i in range(n):

    h = base.copy()
    for j in range(i,i+n):
        a,num = heappop(h)
        heappush(h, (a+B[j],num+1))
    m = max(i for _,i in h)
    ans = min(ans,m)
print(ans)