INF = 1 << 60
N = int(input())
A = list(map(int, input().split()))  # おもちゃ
M = int(input())
B = list(map(int, input().split()))  # はこ
B.sort(reverse=True)

ans = INF
dp = [[False] * (1 << N) for _ in range(M+1)]
# i : i 番目の箱までみて
# j : 箱に入れたおもちゃ達 j (ビット列)
dp[0][0] = True
mask = (1 << N) - 1
for i in range(M):
    for a in range(1 << N):
        if dp[i][a] == 0: continue

        bmask = mask ^ a
        b = bmask
        while b:  # 箱 i に入れるおもちゃ(ビット列)
            cap = 0
            for k in range(N):
                if b & (1 << k):
                    cap += A[k]

            if cap <= B[i]:
                dp[i+1][a | b] = True
                if (a | b) == mask:
                    ans = min(ans, i+1)

            b = (b - 1) & bmask

if ans == INF:
    print(-1)
else:
    print(ans)