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#include <bits/stdc++.h>

using namespace std;

int main()
{
    ios_base::sync_with_stdio(false);
    
    unsigned int n, i, onesCount = 0;
    
    cin >> n;
    vector<unsigned int> a(n);
    for (i = 0; i < n; ++i)
    {
        cin >> a[i];
        if (a[i] == 1)
            ++onesCount;
    }
    
    cout << (onesCount >= 2 ? 0 : (2 - onesCount)) << "\n";
    cout << "2\n" << "1 2\n";

    return 0;
}