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#include <iostream>
using namespace std;

int main() {
	int n;
	cin >> n;
	int a = 0;

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

	cout << max(2-a, 0) << endl << 2 << endl << 1 << " " << 2 << endl;
}