#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<int> a[MAX * 2];
int b[MAX], dist[MAX * 2], visited[MAX * 2], pre[MAX * 2], n, s, t, cnt;
vector<int> res;

void BFS(int u) {
    for (int i = 1; i <= oo * 2; i++) {
        dist[i] = -1;
        pre[i] = -1;
    }
    dist[u] = 0;
    queue<int> 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();
}