import heapq
N = int(input())
A = list(map(int, input().split()))
A.sort()
B = [int(x)//2 for x in input().split()]
H = [(a,0) for a in A]
# heapq.heapify(H)
min_max_cnt = N
for i in range(N):
    h = H[:]
    for j in range(N):
        t = h[0]
        heapq.heapreplace(h, (B[j-i]+t[0], t[1]+1))
    min_max_cnt = min(min_max_cnt, max(t[1] for t in h))
print(min_max_cnt)