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#include <iostream>

using namespace std;

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