#!/usr/bin/env python3
import sys
input = sys.stdin.readline
from heapq import heappush, heappop

n = int(input())
a = [int(item) for item in input().split()]
b = [int(item) for item in input().split()]

ans = 10**9 
for diff in range(n):
    hq = []
    ret = 0
    for item in a:
        heappush(hq, (item, 0))
    for i in range(diff, diff + n):
        lv, times = heappop(hq)
        heappush(hq, (lv + b[i % n] // 2, times + 1))
        if ret < times + 1:
            ret = times + 1
    ans = min(ans, ret)
print(ans)