#include <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define chmax(a, b) a = max(a, b)
#define chmin(a, b) a = min(a, b)
#define all(x) (x).begin(), (x).end()
using namespace std;
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;

int n, m;
VI a, b;
int ans = 100;
VVI division;
void dfs(int k, int nxt=0) {
    if (k == n) {
        VI s(nxt);
        rep(i, nxt) for(int v: division[i]) s[i] += v;
        sort(s.rbegin(), s.rend());
        bool ok = true;
        rep(i, nxt) {
            if (s[i] > b[i]) {
                ok = false;
                break;
            }
        }
        if (ok) {
            chmin(ans, nxt);
        }
        return;
    }
    rep(i, nxt) {
        division[i].push_back(a[k]);
        dfs(k + 1, nxt);
        division[i].pop_back();
    }
    if (nxt < m) {
        division[nxt].push_back(a[k]);
        dfs(k + 1, nxt + 1);
        division[nxt].pop_back();
    }
}

int main() {
    cin >> n;
    a.resize(n);
    rep(i, n) cin >> a[i];
    cin >> m;
    division.resize(m);
    b.resize(m);
    rep(i, m) cin >> b[i];
    sort(b.rbegin(), b.rend());
    dfs(0);
    if (ans == 100) ans = -1;
    cout << ans << endl;
}