#include<bits/stdc++.h>
using namespace std;
#define endl "\n"
#define pb push_back
#define pf push_front
#define pob pop_back
#define pof pop_front
#define mp make_pair
#define fi first
#define se second
#define set_bits __builtin_popcountll
#define precise(ans)  cout<<fixed<<setprecision(15)<<ans
#define fo(i,n) for(ll i=0;i<n;i++)
#define Fo(i,k,n) for(ll i=k;k<n?i<n:i>n;k<n?i+=1:i-=1)
#define tr(it, a) for(auto it = a.begin(); it != a.end(); it++)
#define sz(x) ((ll)(x).size())
#define all(x) x.begin(), x.end()
#define PI 3.1415926535897932384626
#define MOD 1000000007
#define MOD1 998244353
typedef long long ll; typedef unsigned long long ull; typedef long double lld; typedef pair<ll, ll>  pii; typedef pair<ll, ll>    pl; typedef vector<ll> vi; typedef vector<vi> vvi; typedef vector<vvi>    vvvi; typedef vector<ll>  vl; typedef vector<vl>  vvl; typedef vector<pii> vpii; typedef vector<pl>  vpl; template <typename T> using prq_mx  = priority_queue<T>; template <typename T> using prq_mn = priority_queue<T, vector<T>, greater<T>>;
const double eps = 1e-9; const ll INF = (ll) 1e9; const ll inf64 = 2e18; const ll INF64 = 9e18;
#ifndef ONLINE_JUDGE
#define debug(x) cerr << #x <<" "; _prll(x); cerr << endl;
#else
#define debug(x)
#endif
void _prll(ll t) {cerr << t;} void _print(ll t) {cerr << t;} void _prll(string t) {cerr << t;} void _prll(char t) {cerr << t;} void _prll(lld t) {cerr << t;} void _prll(double t) {cerr << t;} void _prll(ull t) {cerr << t;} template <class T, class V> void _prll(pair <T, V> p); template <class T> void _prll(vector <T> v); template <class T> void _prll(set <T> v); template <class T, class V> void _prll(map <T, V> v); template <class T> void _prll(multiset <T> v); template <class T, class V> void _prll(pair <T, V> p) {cerr << "{"; _prll(p.fi); cerr << ","; _prll(p.se); cerr << "}";} template <class T> void _prll(vector <T> v) {cerr << "[ "; for (T i : v) {_prll(i); cerr << " ";} cerr << "]";} template <class T> void _prll(set <T> v) {cerr << "[ "; for (T i : v) {_prll(i); cerr << " ";} cerr << "]";} template <class T> void _prll(multiset <T> v) {cerr << "[ "; for (T i : v) {_prll(i); cerr << " ";} cerr << "]";} template <class T, class V> void _prll(map <T, V> v) {cerr << "[ "; for (auto i : v) {_prll(i); cerr << " ";} cerr << "]";}
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ll max_N=3e5+100;
vl primeFactorize2(ll x) {
    ll num = x;
     vl store;
      for (ll i = 2; i <= sqrt(x); i++) {
        if(num%i==0){
          store.pb(i);
         while ((num % i) == 0) {
            num /= i;
        }
        }
  }
  if (num > 1){
    store.pb(num);
  }
return store;
}



void  chal(){
  ll n;
  cin>>n;
  vl aa(n+1);
  Fo(i,1,n+1)cin>>aa[i];
  debug(aa);
  ll s,d;
  cin>>s>>d;
     if (aa[s] == aa[d]) {
        if (s == d) {
            cout << "1\n" << s<< '\n';
        } else if (aa[s] == 1) {
            cout << -1;
        } else {
            cout << "2\n" << s << " " << d;
        }
        return ;
    }
  vvl bb(max_N);
  vector<vl> cc(n+1);
  Fo(i,1,n+1){
    cc[i]=primeFactorize2(aa[i]);
    fo(j,sz(cc[i])){
      bb[cc[i][j]].pb(i);
    }
  }
  vl dis(n+1,INF64);
  vl par(n+1,-1);
  vl vis(n+1,0);
  queue<ll> q;
  q.push(s);
  par[s]=0;
  vis[s]=1;
  dis[s]=0;
  while(!q.empty()){
    auto node=q.front();
    // cout<<aa[node]<<"->";
    q.pop();
    for(auto ch1:cc[node]){
      for(auto ch2:bb[ch1]){
        if(!vis[ch2]){
          // cout<<aa[ch2]<<" ";
          dis[ch2]=dis[node]+1;
          vis[ch2]=1;
          par[ch2]=node;
          q.push(ch2);
        }
      }
      bb[ch1].clear();
    }
    // cout<<endl;
  }
  if(dis[d]==INF64){
    cout<<-1<<endl;
    return;
  }
  vl ans;
  while(par[d]!=0){
    ans.pb(d);
    d=par[d];
  }
  ans.pb(s);
  debug(ans);
  reverse(all(ans));
  cout<<ans.size()<<endl;
  fo(i,sz(ans)){
    cout<<ans[i]<<" ";
  }
  cout<<endl;
  // cout<<dis[d]<<endl;






}






//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
int32_t main() {
  ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0); srand(chrono::high_resolution_clock::now().time_since_epoch().count());
#ifndef ONLINE_JUDGE
  freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout); freopen("Error.txt", "w", stderr);
#endif
  ll  t; t = 1;
  // cin >> t;
  for (ll i = 1; i <= t; i++) {
    chal();
  } return 0;
}