#include <bits/stdc++.h>

using namespace std;

bool dp[1 << 10];

int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	int n;
	cin >> n;
	vector<int> a(n);
	for (int i = 0; i < n; i++) cin >> a[i];
	int m;
	cin >> m;
	vector<int> b(m);
	for (int i = 0; i < m; i++) cin >> b[i];
	sort(a.rbegin(), a.rend());
	sort(b.rbegin(), b.rend());
	dp[0] = true;
	for (int i = 0; i < m; i++) {
		for (int j = (1 << n) - 2; j >= 0; j--) {
			if (!dp[j]) continue;
			int rest = b[i];
			int s = j;
			for (int k = 0; k < n; k++) {
				if (j & (1 << k)) continue;
				if (rest < a[k]) continue;
				dp[s | (1 << k)] |= dp[s];
				s |= (1 << k);
				rest -= a[k];
			}
		}
		if (dp[(1 << n) - 1]) {
			cout << i + 1 << endl;
			return 0;
		}
	}
	cout << -1 << endl;
	return 0;
}