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#include <iostream>

using namespace std;

int main() {
	int n, k, a;
	k = 0;
	cin >> n;
	for(int i=0; i<n; ++i) {
		cin >> a;
		if(a == 1) k++;
	}
	if(k == 0) cout << "2";
	else if(k == 1) cout << "1";
	else cout << "0";
	cout << endl << "2" << endl;
	cout << "1 2" << endl;
	return 0;
}