pragma GCC optimize("Ofast,unroll-loops")

pragma GCC target("avx,avx2,fma")

include <bits/stdc++.h>

using namespace std;

const int MAX = 3e5 + 2; const int oo = 3e5; vector a[MAX * 2]; int b[MAX], dist[MAX * 2], visited[MAX * 2], pre[MAX * 2], n, s, t, cnt; vector res;

void BFS(int u) { for (int i = 1; i <= oo * 2; i++) { dist[i] = -1; pre[i] = -1; } dist[u] = 0; queue q; q.push(u); visited[u] = 1; while (!q.empty()) { int x = q.front(); q.pop(); for (auto i : a[x]) { if (visited[i] == 0) { visited[i] = 1; pre[i] = x; dist[i] = dist[x] + 1; q.push(i); } } } }

void solve() { cin >> n; for (int i = 1; i <= n; i++) { cin >> b[i]; for (int j = 2; j <= int(sqrt(b[i])); j++) { if (b[i] % j == 0) { a[j + oo].push_back(i); a[i].push_back(j + oo); if (j * j != b[i]) { a[b[i] / j + oo].push_back(i); a[i].push_back(b[i] / j + oo); } } } if (b[i] != 1) { a[b[i] + oo].push_back(i); a[i].push_back(b[i] + oo); } } cin >> s >> t; BFS(s); if (visited[t] == 0) { cout << -1; return; } /*for (int i = 1; i <= n; i++) cout << pre[i] << " "; cout << "\n";*/ /*for (int i = int(3e5) + 1; i <= int(3e5) + 20; i++) { for (auto j : a[i]) cout << j << " "; cout << "\n"; }*/ int k = t; cnt = 1; res.push_back(k); while (pre[k] != -1) { k = pre[k]; cnt++; if (cnt % 2 == 1) res.push_back(k); } cout << res.size() << "\n"; reverse(res.begin(), res.end()); for (int i = 0; i < res.size(); i++) cout << res[i] << " "; }

int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); solve(); }