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#include <iostream>

using namespace std;

int n,a,l=0;

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