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#include <bits/stdc++.h>

using namespace std;
int n;
int k;
int a[1000000];
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    cin >> n;
    int ones = 0;
    for(int i = 0; i < n; i ++){
        cin >> a[i];
        if(a[i] == 1) ones ++;
    }
    if(ones == 0){
        k = 2;
    }
    else if(ones == 1){
        k = 1;
    }
    else k = 0;
    cout << k << "\n";
    cout << 2 << "\n";
    cout << 1 << " " << 2;
    return 0;
}