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#include <iostream>
using namespace std;

int main() {
	// your code goes here
	ios_base::sync_with_stdio(0);
	int n, cnt=0;
	cin >> n;
	for(int i=0; i<n;++i) {
		int x; cin >> x; if (x==1) cnt++;
	}
	
	int res = 0;
	if (cnt == 0) res = 2;
	if (cnt == 1) res = 1;
	cout << res << "\n";
	cout << "2\n1 2\n";
	
	return 0;
}