#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, s, e) for (int i = (int)s; i < (int)e; ++i)
#define all(a) (a).begin(), (a).end()

int main() {
    cin.tie(nullptr);
    
    int D;
    cin >> D;
    
    vector<ll> a(D + 1);
    rep(i, 0, D + 1) cin >> a[i];
    
    reverse(all(a));
    
    rep(i, 0, D - 2) a[i + 2] += a[i];
    
    reverse(all(a));
    
    if (a[0] == 0 && a[1] == 0 && a[2] == 0) {
        cout << 0 << '\n' << 0 << '\n';
    } else if (a[1] == 0 && a[2] == 0) {
        cout << 0 << '\n';
        cout << a[0] << '\n';
    } else if (a[2] == 0) {
        cout << 1 << '\n';
        cout << a[0] << ' ' << a[1] << '\n';
    } else {
            cout << 2 << '\n';
        cout << a[0] << ' ' << a[1] << ' ' << a[2] << '\n';
    }
}