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#include <bits/stdc++.h>
using namespace std;
int main()
{
	ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
	int n;
	cin >> n;
	vector <int> A(n); int ones = 0;
	for (int i = 0; i < n; i++) {
		cin >> A[i];
		if (A[i] == 1)
			ones++;
	}
	cout << max(2-ones, 0) <<endl;
	cout << 2 <<endl;
	cout << 1 << " " << 2 <<endl;
	return 0;
}