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#include <iostream>
using namespace std;

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n,a,cnt=0;
    cin>>n;
    while(n--) {
        cin>>a;
        if(a == 1) ++cnt;
    }
    cout << max(0, 2 - cnt) << '\n';
    cout << "2\n1 2\n";
}