#include "bits/stdc++.h"
using namespace std;
#define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i))
#define rep(i,j) FOR(i,0,j)
#define each(x,y) for(auto &(x):(y))
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define debug(x) cout<<#x<<": "<<(x)<<endl
#define smax(x,y) (x)=max((x),(y))
#define smin(x,y) (x)=min((x),(y))
#define MEM(x,y) memset((x),(y),sizeof (x))
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;

int main(){
    int N, M; cin >> N;
    vi A(N);
    rep(i, N)cin >> A[i];
    cin >> M;
    vi B(M), b(M);
    rep(i, M)cin >> B[i];
    sort(all(A));
    sort(all(B), greater<int>());
    int ans = 100;
    do{
        int i = 0, j = 0;
        copy(all(B), b.begin());
        while(i < N&&j < M){
            if(A[i] <= b[j])b[j] -= A[i++];
            else j++;
        }
        if(j < M)smin(ans, j + 1);
    } while(next_permutation(all(A)));
    cout << (ans != 100 ? ans : -1) << endl;
}