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#include <bits/stdc++.h>

using namespace std;

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL); cout.tie(NULL);
	int n, ones = 0; cin >> n;
	for(int i = 0; i < n; i++)
	{
		int temp; cin >> temp;
		if(temp == 1)
			++ones;
	}
	cout << 2 - min(ones, 2) << endl;
	cout << 2 << endl;
	cout << 1 << " " << 2 << endl;
}