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#include <iostream>

using namespace std;

int main()
{
    cin.tie(0);
    cout.tie(0);
    ios_base::sync_with_stdio(0);
    int n, m;
    int l=0;
    cin >> n;
    for(int i=0; i<n; ++i)
    {
        cin >> m;
        if(m==1) l++;
    }
    if(l==0) cout << 2 << endl;
    else if(l==1) cout << 1 << endl;
    else cout << 0 << endl;
    cout << 2 << endl;
    cout << "1 2" << endl;
    return 0;
}