#include <bits/stdc++.h>
using namespace std;
template <class T>
inline bool chmax(T& a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
inline bool chmin(T& a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T1, class T2>
ostream& operator<<(ostream& s, pair<T1, T2> P) {
  return s << '<' << P.first << ", " << P.second << '>';
}
template <class T>
ostream& operator<<(ostream& s, vector<T> P) {
  for (int i = 0; i < P.size(); ++i) {
    if (i > 0) {
      s << " ";
    }
    s << P[i];
  }
  return s;
}
template <class T>
ostream& operator<<(ostream& s, vector<vector<T> > P) {
  for (int i = 0; i < P.size(); ++i) {
    s << endl << P[i];
  }
  return s << endl;
}
template <class T1, class T2>
ostream& operator<<(ostream& s, map<T1, T2> P) {
  for (__typeof__((P).begin()) it = (P).begin(); it != (P).end(); ++it) {
    s << "<" << it->first << "->" << it->second << "> ";
  }
  return s << endl;
}
int N;
int main() {
  while (cin >> N) {
    long long res = 0;
    bool isM = false;
    long long a;
    cin >> a;
    res = a;
    for (int i = 1; i < N; ++i) {
      char c;
      cin >> c >> a;
      if (isM)
        res += abs(a);
      else {
        if (c == '-') {
          isM = true;
          res -= a;
        } else {
          res += a;
        }
      }
    }
    cout << res << endl;
  }
}
