Problem p02984 (C++)

Buggy submission (status: Runtime Error):
// include
// ------------------------------------------------
#include <bits/stdc++.h>
#include <math.h>

using namespace std;

// func
// ------------------------------------------------
int CalcSumOfDigit(int n); // 各桁の和を計算する。
int getDigit(int n);       // 数字の桁数を取得する。
string upper(string str);  // 英字を大文字に変換する。
string lower(string str);  // 英字を小文字に変換する。
vector<pair<long long, long long>> prime_factorize(long long p); // 素因数分解

// class
// ------------------------------------------------
class Combi {
public:
  Combi();
  long long Combination(long long n, long long k);
  long long nPk_modp(long long n, long long k, long long p);

private:
  map<long long, map<long long, long long>> memo;
  long long n_num;
  long long k_num;
};

// define
// ------------------------------------------------
#define all(a) (a).begin(), (a).end()
#define rall(a) (a).rbegin(), (a).rend()
#define sz(a) int((a).size())
#define rep(i, n) for (long long(i) = 0; (i) < (n); (i)++)
#define repe(i, n) for (long long(i) = 0; (i) <= (n); (i)++)
#define vsort(v) sort((v).begin(), (v).end())
#define rvsort(v) sort(rall((v)))
#define vi vector<int>
#define GCD(a, b) __gcd((a), (b))
#define LCM(a, b) (a) / GCD((a), (b)) * (b)
#define kiriage(a, b) ((a) + (b)-1) / (b)

const int INF = 1e9;

typedef long long ll;
typedef unsigned long long ull;
typedef vector<long> vll;
// code
// ------------------------------------------------
int main() {

  ll n;
  cin >> n;

  vll a(n);
  rep(i, n) cin >> a[i];

  ll sum = 0;
  rep(i, n) { sum += a[i]; }

  ll sum2 = 0;
  for (ll i = 1; i < n; i = i + 2) {
    sum2 += a[i];
  }

  vll x(n);
  x[0] = sum - sum2 * 2;

  rep(i, n) { x[i + 1] = 2 * a[i] - x[i]; }

  rep(i, n) {
    if (i == 0)
      cout << x[i];
    else
      cout << " " << x[i];
  }
  cout << endl;

  return 0;
}
// funcの実体
// ------------------------------------------------
int getDigit(int n) {
  int i = 1;
  while (1) {
    n = n / 10;
    if (n == 1)
      break;
    i++;
  }
  return i;
}
int CalcSumOfDigit(int n) {
  int s = 0;
  while (n) {
    s += n % 10;
    n = n / 10;
  }
  return s;
}

string upper(string str) {
  for (auto itr = str.begin(); itr != str.end(); itr++) {
    if (97 <= *itr && *itr <= 122) {
      *itr = *itr - 32;
    }
  }
  return str;
}

string lower(string str) {
  for (auto itr = str.begin(); itr != str.end(); itr++) {
    if (65 <= *itr && *itr <= 90) {
      *itr = *itr + 32;
    }
  }
  return str;
}

Combi::Combi() {
  n_num = -1;
  k_num = -1;
};

ll Combi::Combination(ll n, ll k) {

  ll ret;
  if (memo[n][k] != 0) {
    ret = memo[n][k];
  } else if (n == k || k == 0) {
    memo[n][k] = 1;
    ret = 1;
  } else {
    ret = Combination(n - 1, k - 1) + Combination(n - 1, k);
    memo[n][k] = ret;
  }
  return ret;
}

long long Combi::nPk_modp(long long n, long long k, long long p) {
  ll ans = 1;
  for (long long i = k; i <= n; i++) {
    ans = (ans * i) % p;
  }

  return ans;
};

vector<pair<long long, long long>> prime_factorize(long long p) {
  vector<pair<long long, long long>> ret;

  for (long long x = 2; x * x <= p; ++x) {
    if (p % x != 0)
      continue;
    long long num = 0;
    while (p % x == 0) {
      num++;
      p /= x;
    }
    ret.push_back(make_pair(x, num));
  }

  if (p != 1)
    ret.push_back(make_pair(p, 1));

  return ret;
}

Fixed submission:
// include
// ------------------------------------------------
#include <bits/stdc++.h>
#include <math.h>

using namespace std;

// func
// ------------------------------------------------
int CalcSumOfDigit(int n); // 各桁の和を計算する。
int getDigit(int n);       // 数字の桁数を取得する。
string upper(string str);  // 英字を大文字に変換する。
string lower(string str);  // 英字を小文字に変換する。
vector<pair<long long, long long>> prime_factorize(long long p); // 素因数分解

// class
// ------------------------------------------------
class Combi {
public:
  Combi();
  long long Combination(long long n, long long k);
  long long nPk_modp(long long n, long long k, long long p);

private:
  map<long long, map<long long, long long>> memo;
  long long n_num;
  long long k_num;
};

// define
// ------------------------------------------------
#define all(a) (a).begin(), (a).end()
#define rall(a) (a).rbegin(), (a).rend()
#define sz(a) int((a).size())
#define rep(i, n) for (long long(i) = 0; (i) < (n); (i)++)
#define repe(i, n) for (long long(i) = 0; (i) <= (n); (i)++)
#define vsort(v) sort((v).begin(), (v).end())
#define rvsort(v) sort(rall((v)))
#define vi vector<int>
#define GCD(a, b) __gcd((a), (b))
#define LCM(a, b) (a) / GCD((a), (b)) * (b)
#define kiriage(a, b) ((a) + (b)-1) / (b)

const int INF = 1e9;

typedef long long ll;
typedef unsigned long long ull;
typedef vector<long> vll;
// code
// ------------------------------------------------
int main() {

  ll n;
  cin >> n;

  vll a(n);
  rep(i, n) cin >> a[i];

  ll sum = 0;
  rep(i, n) { sum += a[i]; }

  ll sum2 = 0;
  for (ll i = 1; i < n; i = i + 2) {
    sum2 += a[i];
  }

  vll x(n + 1);
  x[0] = sum - sum2 * 2;

  rep(i, n) { x[i + 1] = 2 * a[i] - x[i]; }

  rep(i, n) {
    if (i == 0)
      cout << x[i];
    else
      cout << " " << x[i];
  }
  cout << endl;

  return 0;
}
// funcの実体
// ------------------------------------------------
int getDigit(int n) {
  int i = 1;
  while (1) {
    n = n / 10;
    if (n == 1)
      break;
    i++;
  }
  return i;
}
int CalcSumOfDigit(int n) {
  int s = 0;
  while (n) {
    s += n % 10;
    n = n / 10;
  }
  return s;
}

string upper(string str) {
  for (auto itr = str.begin(); itr != str.end(); itr++) {
    if (97 <= *itr && *itr <= 122) {
      *itr = *itr - 32;
    }
  }
  return str;
}

string lower(string str) {
  for (auto itr = str.begin(); itr != str.end(); itr++) {
    if (65 <= *itr && *itr <= 90) {
      *itr = *itr + 32;
    }
  }
  return str;
}

Combi::Combi() {
  n_num = -1;
  k_num = -1;
};

ll Combi::Combination(ll n, ll k) {

  ll ret;
  if (memo[n][k] != 0) {
    ret = memo[n][k];
  } else if (n == k || k == 0) {
    memo[n][k] = 1;
    ret = 1;
  } else {
    ret = Combination(n - 1, k - 1) + Combination(n - 1, k);
    memo[n][k] = ret;
  }
  return ret;
}

long long Combi::nPk_modp(long long n, long long k, long long p) {
  ll ans = 1;
  for (long long i = k; i <= n; i++) {
    ans = (ans * i) % p;
  }

  return ans;
};

vector<pair<long long, long long>> prime_factorize(long long p) {
  vector<pair<long long, long long>> ret;

  for (long long x = 2; x * x <= p; ++x) {
    if (p % x != 0)
      continue;
    long long num = 0;
    while (p % x == 0) {
      num++;
      p /= x;
    }
    ret.push_back(make_pair(x, num));
  }

  if (p != 1)
    ret.push_back(make_pair(p, 1));

  return ret;
}