n = int(input())
*a, = [(int(i),0) for i in input().split()]
*b, = map(int,input().split())
for i in range(n):
    b[i] //= 2
b += b

from heapq import *
ans = 1<<30
for i in range(n):
    q = a[:]
    heapify(q)
    for j in range(i,i+n):
        v,t = heappop(q)
        heappush(q,(v+b[j],t+1))
    x = max(t for v,t in q)
    if x < ans:
        ans = x
print(ans)