#include <bits/stdc++.h>
template <typename T>
void MACRO_VAR_Scan(T& t) {
  std::cin >> t;
}
template <typename First, typename... Rest>
void MACRO_VAR_Scan(First& first, Rest&... rest) {
  std::cin >> first;
  MACRO_VAR_Scan(rest...);
}
template <typename T>
void MACRO_VEC_ROW_Init(int n, T& t) {
  t.resize(n);
}
template <typename First, typename... Rest>
void MACRO_VEC_ROW_Init(int n, First& first, Rest&... rest) {
  first.resize(n);
  MACRO_VEC_ROW_Init(n, rest...);
}
template <typename T>
void MACRO_VEC_ROW_Scan(int p, T& t) {
  std::cin >> t[p];
}
template <typename First, typename... Rest>
void MACRO_VEC_ROW_Scan(int p, First& first, Rest&... rest) {
  std::cin >> first[p];
  MACRO_VEC_ROW_Scan(p, rest...);
}
template <typename T>
inline T CHMAX(T& a, const T b) {
  return a = (a < b) ? b : a;
}
template <typename T>
inline T CHMIN(T& a, const T b) {
  return a = (a > b) ? b : a;
}
void CHECKTIME(std::function<void()> f) {
  auto start = std::chrono::system_clock::now();
  f();
  auto end = std::chrono::system_clock::now();
  auto res = std::chrono::duration_cast<std::chrono::nanoseconds>((end - start))
                 .count();
  std::cerr << "[Time:" << res << "ns  (" << res / (1.0e9) << "s)]\n";
}
using ll = long long;
using ull = unsigned long long;
constexpr ll INFINT = 1 << 30;
constexpr ll INFINT_LIM = (1LL << 31) - 1;
constexpr ll INFLL = 1LL << 60;
constexpr ll INFLL_LIM = (1LL << 62) - 1 + (1LL << 62);
constexpr double EPS = 1e-7;
constexpr ll MOD = 1000000007;
constexpr double PI = 3.141592653589793238462643383279;
signed main() {
  std::ios::sync_with_stdio(false);
  std::cin.tie(0);
  ;
  ll n;
  MACRO_VAR_Scan(n);
  ;
  std::vector<ll> a(n);
  std::vector<char> op(n - 1);
  for (ll i = 0; i < ll(n - 1); ++i) {
    std::cin >> a[i] >> op[i];
  }
  std::cin >> a[n - 1];
  ll sum = 0;
  for (ll i = 0; i < ll(n); ++i) {
    sum += a[i];
  }
  ll cnt = 0;
  for (ll i = 0; i < ll(n - 1); ++i) {
    if (op[i] == '-') {
      if (cnt == 1) break;
      sum -= 2 * a[i + 1];
      ++cnt;
    } else if (op[i] == '+' && cnt == 1) {
      sum -= 2 * a[i + 1];
    }
  }
  std::cout << sum;
  std::cout << "\n";
  ;
  return 0;
}
