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#include<bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;

#define PB push_back
#define ST first
#define ND second

int main()
{
	ios_base::sync_with_stdio(0);
	int n;
	cin >> n;
	int ones=0;
	for(int i=0; i < n; i++)
	{
		int a;
		cin >> a;
		if(a == 1)
			ones++;
	}
	int res=2;
	if(ones == 1)
		res=1;
	else if(ones > 1)
		res=0;
	cout << res << "\n";
	cout << "2\n1 2\n";
	return 0;
}