#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;

#define rep(i,n) for(int i=0;i<(n);i++)

int main(){

  string s; cin>> s;
  int n=s.size();

  bool inside=false; // かっこの中か
  int res=0;
  for(int i=n-1; i>=0; i--){
    if(s[i]==')'){
      inside=true;
    }else if(s[i]=='('){
      int j=i+1, sub=s[j++]-'0'; // ( 3 ...
      while(s[j]!=')'){
        if(s[j]=='+') sub+=s[j+1]-'0'; // (3 + 4 ...
        else if(s[j]=='-') sub-=s[j+1]-'0'; // (3 - 4 ...
        j++;
      }
      int sgn=(i-1>=0 and s[i-1]=='-') ? -1 : 1; // ... - (3 + 4 - ...)
      res+=sub*sgn;
      inside=false;
    }else if('0'<=s[i] and s[i]<='9'){
      if(inside) continue;
      int sub=s[i]-'0',
          sgn=(i-1>=0 and s[i-1]=='-') ? -1 : 1; // ... - 3 ...
      res+=sub*sgn;
    }
  } 
  
  cout<< res<< endl;
  return 0;
}