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

n = int(input())
A = list(map(int, input().split()))
B = list(map(int, input().split()))

H = []
for i in range(n):
    H.append((A[i], 0, i))
heapify(H)
ans = 10**18
for i in range(n):
    Hc = H[:]
    C = [0 for _ in range(n)]
    for j in range(n):
        ii = (i + j) % n
        cl, cc, ci = heappop(H)
        cc += 1
        C[ci] = cc
        cl += B[ii] // 2
        heappush(H, (cl, cc, ci))
    ans = min(ans, max(C))
print(ans)