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#include <iostream>

using namespace std;

typedef unsigned int ui;

int main() {
    ios::sync_with_stdio(false);

    ui n, deg, ones = 0;

    cin >> n;

    while (n--) {
        cin >> deg;
        if (deg == 1) {
            ones++;
        }
    }

    if (ones > 1) {
        cout << 0 << endl;
    } else {
        cout << 2 - ones << endl;
    }

    cout << "2\n1 2" << endl;

    return 0;
}