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#include <iostream>
#include <vector>

using namespace std;

int main() {
	ios_base::sync_with_stdio(0);

	int n; cin >> n;
	int ones = 0, a;
	for (int i = 0; i < n; i++) {
		cin >> a;
		if (a == 1) ones++;
	}

	cout << 2 - min(ones, 2) << endl;
	cout << "2\n1 2\n";

	return 0;
}