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#include <bits/stdc++.h>

using namespace std;
#define int long long

main() {
    int n;
    cin >> n;
    int counter = 0;
    while (n--) {
        int a;
        cin >> a;
        if (a == 1) {
            counter++;
        }
    }
    cout << 2 - min(2LL, counter) << endl;
    cout << 2 << endl;
    cout << 1 << " " << 2 << endl;
}