#include<sstream>
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<string>
#include<vector>
#include<set>
#include<map>
#include<queue>
#include<numeric>
#include<functional>
#include<algorithm>
#include<bitset>
using namespace std;
#define INF (1<<29)
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define all(v) v.begin(),v.end()
#define uniq(v) v.erase(unique(all(v)),v.end())
#define indexOf(v,x) (find(all(v),x)-v.begin())




int main(){
	int n,a[10],m,b[10];
	int ans=INF;
	cin>>n;
	rep(i,n)cin>>a[i];
	cin>>m;
	rep(i,m)cin>>b[i];
	sort(a,a+n);
	sort(b,b+m,greater<int>());
	do{
		int idx=0,cap=b[0];
		rep(i,n){
			if(a[i]<=cap)cap-=a[i];
			else{
				if(m<=++idx)break;
				cap=b[idx]-a[i];
				if(cap<0){
					idx=m;
					break;
				}
			}
		}
		if(idx<m)ans=min(ans,idx+1);
	}while(next_permutation(a,a+n));
	if(ans==INF)ans=-1;
	cout<<ans<<endl;
	return 0;
}