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#include <iostream>

using namespace std;

int n, a, ones;

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