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#include <iostream>

using namespace std;

int main() {
    ios_base::sync_with_stdio(0);
    int ones = 0, d, n;
    
    cin >> n;
    
    for (int i = 0; i < n; i++) {
        cin >> d;
        if (d == 1)
            ones++;
    }
    
    if (ones > 2)
        ones = 2;
        
    cout << 2 - ones << endl;
    
    cout << 2 << endl;
    
    cout << 1 << ' ' << 2 << endl;
        
    
    


}