#include <iostream>
#include <vector>
#include <string>
#include <cstring>
#include <math.h>
#include <cmath>
#include <limits.h>
#include <map>
#include <set>
#include <queue>
#include <algorithm>
#include <functional>
#include <stdio.h>
using namespace std;

long long MOD = 1000000007;

int main() {
    
    int D;
    cin >> D;
    vector<int> A(D+1);
    
    for ( int i = 0; i <= D; i++ ) {
        cin >> A[i];
    }
    
    int f0 = A[0];
    int f1 = 0, f2 = 0;
    
    for ( int i = 0; i <= D; i++ ) {
        f2 += ( i%2 ) ? -A[i] : A[i];
        f1 += A[i];
    }
    
    // cout << f1 << " " << f2 << endl;
    
    int ans[3];    
    
    ans[0] = f0;
    ans[1] = (f1-f2)/2;
    ans[2] = f1-(ans[1]+ans[0]);
    
    
    int d = 0;
    for ( int i = 1; i < 3; i++ ) {
        if ( ans[i] != 0 ) { d = i; }
    }
    cout << d << endl;
    
    for ( int i = 0; i < d+1; i++ ) {
        if ( i ) { cout << " "; }
        cout << ans[i];        
    }
    cout << endl;
    
    return 0;
}