#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
using ll =  long long ;
using P = pair<int,int> ;
const int INF = 1e9;
const int MOD = 1000000007;

int main(){
    string s;
    cin >> s;
    int ans = 0;
    int n = s.size();
    bool plus = true;
    bool close = false;
    bool close_plus = true;
    rep(i,n){
        if(s[i] == '('){
            close = true;
            plus = true;
            if(i>0){
                if(s[i-1] == '-') close_plus = false;
                else close_plus = true;
            }else{
                close_plus = true;
            }
            continue;
        }
        if(s[i] == ')'){
            close = false;
            continue;
        }
        if(s[i] == '+'){
            plus = true;
            continue;
        }
        if(s[i] == '-'){
            plus = false;
            continue;
        }
        if(close){
            ans += (s[i] - '0') * (plus ^ close_plus ? -1 : 1);
        }else{
            ans += (s[i] - '0') * (plus ? 1 : -1); 
        }
    }
    cout << ans << endl;
    return 0;
}