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

B.sort(reverse=True)
V = [0 for _ in range(1 << n)]
for bit in range(1 << n):
    for i in range(n):
        if (bit >> i) & 1:
            V[bit] += A[i]
DP = [[False for _ in range(1 << n)] for _ in range(m + 1)]
DP[0][0] = True
for i in range(m):
    for bit1 in range(1 << n):
        for bit2 in range(1 << n):
            if bit1 & bit2 == 0 and DP[i][bit1] and V[bit2] <= B[i]:
                DP[i + 1][bit1 | bit2] = True
    if DP[i + 1][-1]:
        print(i + 1)
        exit()
print(-1)