#include "bits/stdc++.h"

using namespace std;
using ll = long long;
const double pi = acos(-1);
#define FOR(i,a,b) for (ll i=(a),__last_##i=(b);i<__last_##i;i++)
#define RFOR(i,a,b) for (ll i=(b)-1,__last_##i=(a);i>=__last_##i;i--)
#define REP(i,n) FOR(i,0,n)
#define RREP(i,n) RFOR(i,0,n)
#define __GET_MACRO3(_1, _2, _3, NAME, ...) NAME
#define rep(...) __GET_MACRO3(__VA_ARGS__, FOR, REP)(__VA_ARGS__)
#define rrep(...) __GET_MACRO3(__VA_ARGS__, RFOR, RREP)(__VA_ARGS__)
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v) {
	REP(i, v.size()) { if (i)os << " "; os << v[i]; }return os;
}
template<typename T> ostream& operator<<(ostream& os, const vector<vector<T>>& v) {
	REP(i, v.size()) { if (i)os << endl; os << v[i]; }return os;
}

const ll INF = LLONG_MAX;
ll MOD = 1000000007;
ll _MOD = 1000000009;
double EPS = 1e-10;

#define int long long

inline void my_io() {

	std::ios::sync_with_stdio(false);

	std::cin.tie(0);

	cout << fixed << setprecision(16);

	//cout << setprecision(10) << scientific << ans << endl;
}

signed main() {
	ll d;

	cin >> d;

	vector<ll> v(d + 1);
	ll x[4] = { 1, 0, -1, 0 };

	REP(i, d + 1) {
		cin >> v[i];
	}

	if (d < 3) {
		cout << d << endl;
		cout << v << endl;
	}
	else {
		ll n;

		RFOR(i, 3, d + 1) {
			n = v[i];

			REP(j, 4) {
				v[i - j] -= x[j] * n;
			}
		}

		if (v[2] != 0) {
			cout << 2 << endl;
			cout << v[0] << " " << v[1] << " " << v[2] << endl;
		}
		else if (v[1] != 0) {
			cout << 1 << endl;
			cout << v[0] << " " << v[1] << endl;
		}
		else {
			cout << 0 << endl;
			cout << v[0] << endl;
		}
	}
}