def next_permutation(arr):
    i = len(arr) - 2
    while i >= 0 and arr[i] >= arr[i + 1]:
        i -= 1
    if i == -1:
        return False
    j = len(arr) - 1
    while arr[j] <= arr[i]:
        j -= 1
    arr[i], arr[j] = arr[j], arr[i]
    arr[i + 1:] = reversed(arr[i + 1:])
    return True
from itertools import permutations
n = int(input())
A = sorted(map(int, input().split()))
m = int(input()) + 1
B = list(reversed(sorted(map(int, input().split()))))
a = m
while True:
    T, i, j = B[:], 0, 0
    while i < n and j < m - 1:
        if T[j] >= A[i]:
            T[j] -= A[i]
            i += 1
        else:
            j += 1
    a = min(a, j + 1)
    if not next_permutation(A):
        break
print(a if a < m else -1)