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

#ifdef LOCAL
template<class T, class U>
ostream& operator<<(ostream& os, pair<T, U> p) {
	return os << "(" << p.first << ", " << p.second << ")";
}

template<class C, class = typename C::value_type>
typename enable_if<!is_same<C, string>::value, ostream&>::type 
operator<<(ostream& os, C c) {
	for (auto i = c.begin(); i != c.end(); i++) {
		os << " {"[i == c.begin()] << *i << ",}"[next(i) == c.end()];
	}
	return os;
}

#define debug(x) { cerr << #x << " = " << x << endl; }
#else
#define debug(...) {}
#endif

void answer(int x) {
	cout << x << "\n";
	cout << "2\n";
	cout << "1 2\n";
}

int main() {
	int n;
	cin >> n;
	vector<int> in;
	int one_count = 0;
	for (int i = 0; i < n; i ++) {
		int x;
		cin >> x;
		in.push_back(x);
		if (x == 1) one_count ++;
	}
	if (one_count >= 2) {
		answer(0);
	} else if (one_count == 1) {
		answer(1);
	} else if (one_count == 0) {
		answer(2);
	}
}