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#include <bits/stdc++.h>
using namespace std;

int main() {
	ios_base::sync_with_stdio(false);
	
	int n;
	cin >> n;
	
	int j = 0;
	for (int i = 0; i < n; i++) {
		int d;
		cin >> d;
		if (d == 1)
			j++;
	}
	j = min(2, j);
	cout << 2 - j << endl << 2 << endl << 1 << ' ' << 2 << endl;
	
	return 0;
}