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#include <iostream>

using namespace std;

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin >> n;

    int ctr = 0;
    for (int i = 0; i < n; i++)
    {
        int a;
        cin >> a;
        if (a == 1) ctr++;
    }

    cout << max(0, 2 - ctr) << "\n";
    cout << 2 << "\n" << 1 << " " << 2 << "\n";
}