#include<bits/stdc++.h>
using namespace std;
#define inf INT_MAX
#define INF LLONG_MAX
#define ll long long
#define ull unsigned long long
#define M (int)(1e9+7)
#define P pair<int,int>
#define PLL pair<ll,ll>
#define FOR(i,m,n) for(int i=(int)m;i<(int)n;i++)
#define RFOR(i,m,n) for(int i=(int)m;i>=(int)n;i--)
#define rep(i,n) FOR(i,0,n)
#define rrep(i,n) RFOR(i,n,0)
#define all(a) a.begin(),a.end()
#define IN(a,n) rep(i,n){ cin>>a[i]; }
const int vx[4] = {0,1,0,-1};
const int vy[4] = {1,0,-1,0};
#define PI 3.14159265
#define F first
#define S second
#define PB push_back
#define EB emplace_back
#define int ll
#define vi vector<int>
#define IP pair<int,P>
#define PP pair<P,P>
#define Yes(f){cout<<(f?"Yes":"No")<<endl;}
#define YES(f){cout<<(f?"YES":"NO")<<endl;}

int n;
vi d;
int x,y;
map<int,int> mp;

void f(int s,int k,int i){

  if(mp.find(s)==mp.end()) mp[s]=k;
  else mp[s]=min(mp[s],k);

  if(i==n) return;

  f(s+d[i],k+1,i+1);
  f(s,k,i+1);
  f(s-d[i],k+1,i+1);
}



signed main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout<<fixed<<setprecision(20);

  cin>>n;
  d=vi(n);
  rep(i,n){
    cin>>d[i];
  }

  f(0,0,0);

  cin>>x>>y;
  int a=max(abs(x),abs(y));

  int ans=inf;

  for(P m:mp){
    if(m.F<=0) continue;
    if(a%m.F!=0) continue;
    ans=min(ans,m.S*a/m.F);
  }

  cout<<(ans==inf?-1:ans)<<endl;


}