#include <bits/stdc++.h>
using namespace std;


int main()
{
    int n;
    cin >> n;
    vector <int> a(n + 1);
    for (int i = 1; i <= n; i++)
        cin >> a[i];
    int m;
    cin >> m;
    vector <int> b(m + 1);
    for (int i = 1; i <= m; i++)
        cin >> b[i];
    vector <int> pr(m + 1, -1);
    vector <vector <int> > dp(n + 1, vector<int>(m + 1));
    for (int i = 1; i <= n; i++)
    {
        int p = 0;
        int ind = 0;
        for (int j = 1; j <= m; j++)
        {
            if (a[i] != b[j])
                dp[i][j] = dp[i - 1][j];
            if (a[i] == b[j])
                if (p + 1 > dp[i - 1][j])
                {
                    pr[j] = ind;
                    dp[i][j] = p + 1;
                }
                else
                    dp[i][j] = dp[i - 1][j];
            if (dp[i][j] > p && b[j] < a[i])
            {
                p = dp[i][j];
                ind = j;
            }
        }
    }
    /*for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= m; ++j)
            cout << dp[i][j] << " ";
        cout << '\n';
    }
    for (int j = 1; j <= m; ++j)
        cout << pr[j] << " "; */
    int pos = 0;
    for (int i = 1; i <= m; i++)
    {
        if (dp[n][i] > dp[n][pos])
            pos = i;
    }
    vector <int> ot;
    while (pr[pos] != -1)
    {
        ot.push_back(b[pos]);
        pos = pr[pos];
    }
    //ot.push_back(b[pos]);
    cout << ot.size() << endl;
    for (auto it = ot.rbegin(); it != ot.rend(); it++)
        cout << *it << " ";
    system("pause");
}