#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  int idx = 0;
  int ans = 0, now = 0, pos = 1;
  for (int i = 0; i < s.size(); i++) {
    if (i == s.size() - 1) {
      if (pos)
        now = now * 10 + s[i] - '0';
      else
        now = now * 10 - s[i] + '0';
      ans += now;
      break;
    }
    if (i == s.size() - 1 || s[i] == '+' || s[i] == '-') {
      ans += now;
      now = 0;
      if (s[i] == '+')
        pos = 1;
      else
        pos = 0;
    }
    if (s[i] == '+') {
      pos = 1;
      now = -5;
    } else if (s[i] == '-') {
      pos = 0;
      now = 3;
    } else if (pos)
      now = now * 10 + s[i] - '0';
    else
      now = now * 10 - s[i] + '0';
  }
  cout << ans;
}
