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#include <bits/stdc++.h>

using namespace std;

int main() {

    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    int n;
    cin >> n;

    int ones = 0;
    for (int i = 0; i < n; ++i) {
        int a;
        cin >> a;

        if (a == 1) {
            ++ones;
        }
    }

    ones = min(ones, 2);

    cout << 2 - ones << '\n';
    cout << "2\n1 2\n";

    return 0;
}