#include <bits/stdc++.h>
using namespace std;

int main(){
  string s; cin >> s;
  stack<int> op; bool braket = false;
  int ans = -1e5; int tmp = -1e5;
  for (int i = 0; i < (int) s.size(); i++) {
    if (s[i] == '+') op.push(1);
    else if (s[i] == '-') op.push(-1);
    else if (s[i] == '(') {
      braket = true;
    } else if (s[i] == ')') {
      braket = false;
      ans += op.top() * tmp;
      tmp = -1e5; op.pop();
    } else {
      int n = s[i] - '0';
      if (braket) {
        if (tmp == -1e5) tmp = n;
        else {
          tmp += op.top() * n;
          op.pop();
        }
      } else {
        if (ans == -1e5) ans = n;
        else {
          ans += op.top() * n;
          op.pop();  
        }
      }
    }
  }
  cout << ans << endl;
  return 0;
}