N = int(input())
A = [int(x) for x in input().split()]
B = [int(x) for x in input().split()]
min_max_cnt = N
for start in range(N):
    H = [(a,0) for a in A]
    for i in range(N):
        H.sort()
        H[0] = ((B[i-start]-H[0][0]+1)//2+H[0][0] , H[0][1]+1)
    min_max_cnt = min(min_max_cnt, max([H[i][1] for i in range(N)]))
print(min_max_cnt)