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#include <iostream>

#include <iostream>
using namespace std;

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