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#include <iostream>

using namespace std;

int main()
{
    ios_base::sync_with_stdio(0);
    int n;
    cin >> n;
    int k = 0;
    for (int i = 0;i < n;i++) {
        int a;
        cin >> a;
        if (a == 1)
            k++;
    }
    if (k == 0) {
        cout << 2 << endl;
    } else if (k == 1) {
        cout << 1 << endl;
    } else {
        cout << 0 << endl;
    }
    cout << "2" << endl;
    cout << "1 2"<<endl;
    return 0;
}