from itertools import permutations

N = int(input())
A = list(map(int,input().split()))
M = int(input())
B = list(map(int,input().split()))
B.sort(reverse = True)
ans = M + 1
for P in permutations(A,N):
    j = 0
    now = B[0]
    f = True
    for i in range(N):
        if now >= P[i]:
            now -= P[i]
        else:
            j += 1
            if j < M:
                now = B[j]
                if now >= P[i]:
                    now -= P[i]
                else:
                    f = False
                    break
            else:
                f = False
                break
    if f:
        ans = min(ans,j + 1)
if ans == M + 1:
    print(-1)
else:
    print(ans)