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#include <iostream>
using namespace std;
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int cnt = 0, n; cin >> n;
    while (n--)
    {
        int v; cin >> v; cnt += (v == 1);
    }
    cout << (2 - min(cnt, 2)) << '\n';
    cout << "2\n1 2 \n";
}