#region Header
#!/usr/bin/env python3
# from typing import *

import sys
import io
import math
import collections
import decimal
import itertools
import bisect
import heapq


def input():
    return sys.stdin.readline()[:-1]


# sys.setrecursionlimit(1000000)
#endregion

# _INPUT = """2
# 8 12
# 2
# 10 10
# """
# sys.stdin = io.StringIO(_INPUT)


def main():
    N = int(input())
    A = list(map(int, input().split()))
    M = int(input())
    B = list(map(int, input().split()))
    B.sort(reverse=True)

    ans = 100
    for pat in itertools.permutations(A):
        i = 0
        cap = B[0]
        ok = True
        for item in pat:
            if item <= cap:
                cap -= item
            else:
                i += 1
                if i == N-1 or B[i] < item:
                    ok = False
                    break
                cap = B[i] - item
        if ok:
            ans = min(ans, i+1)

    if ans == 100:
        print(-1)
    else:
        print(ans)

if __name__ == '__main__':
    main()