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#include<iostream>
using namespace std;

int main()
{
        ios_base::sync_with_stdio(0);
        cin.tie(0);
	int n, z = 0;
	cin >> n;
	int a[n];
	for(int i = 0; i < n; i++)
	{
		cin >> a[i];
		if(a[i] == 1) z++;
	}
	
	if(z == 0) cout << 2 << "\n";
	else if(z == 1) cout << 1 << "\n";
	else cout << 0 << "\n";
	
	cout << 2 << "\n";
	cout << 1 << " " << 2 << "\n";
}