#include <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>
  
#define mp       make_pair
#define pb       push_back
#define all(x)   (x).begin(),(x).end()
#define rep(i,n) for(int i=0;i<(n);i++)
  
using namespace std;
  
typedef    long long          ll;
typedef    unsigned long long ull;
typedef    vector<bool>       vb;
typedef    vector<int>        vi;
typedef    vector<vb>         vvb;
typedef    vector<vi>         vvi;
typedef    pair<int,int>      pii;
  
const int INF=1<<29;
const double EPS=1e-9;
  
const int dx[]={1,0,-1,0,1,1,-1,-1},dy[]={0,-1,0,1,1,-1,-1,1};

int main() {
  string s;
  cin >> s;
  int ans = 0;
  int nowop = 1;
  for (int i = 0; i < s.size(); i++) {
    if (s[i] == '(') {
      i++;

      int num1 = 0;
      while(isdigit(s[i])) {
        num1 *= 10;
        num1 += s[i] - '0';
        i++;
      }

      while(1) {
        if (s[i] == ')') break;

        int op = s[i] == '+' ? 1 : -1;

        i++;
        int num2 = 0;
        while(isdigit(s[i])) {
          num2 *= 10;
          num2 += s[i] - '0';
          i++;
        }
        num1 = num1 + op * num2;
      }


      ans += nowop * num1;
    } else {
      if (s[i] == '+') nowop = 1;
      else if (s[i] == '-') nowop = -1;
      else {
        ans += nowop * (s[i] - '0');
      }
    }
  }
  cout << ans << endl;
  return 0;
}