// includes
#include <cstdio>
#include <cstdint>
#include <iostream>
#include <iomanip>
#include <string>
#include <queue>
#include <stack>
#include <vector>
#include <set>
#include <map>
#include <unordered_map>
#include <algorithm>
#include <utility>
#include <functional>
#include <cmath>
#include <climits>
#include <bitset>
#include <list>
#include <random>

// macros
#define ll long long int
#define pb emplace_back
#define mk make_pair
#define pq priority_queue
#define FOR(i, a, b) for(int i=(a);i<(b);++i)
#define rep(i, n) FOR(i, 0, n)
#define rrep(i, n) for(int i=((int)(n)-1);i>=0;i--)
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define UNIQUE(v) v.erase(unique(v.begin(), v.end()), v.end())

using namespace std;

//  types
typedef pair<int, int> P;
typedef pair<ll, int> Pl;
typedef pair<ll, ll> Pll;
typedef pair<double, double> Pd;
 
// constants
const int inf = 1e9;
const ll linf = 1LL << 50;
const double EPS = 1e-10;
const int mod = 1e9 + 7;

// solve
template <class T>bool chmax(T &a, const T &b){if(a < b){a = b; return 1;} return 0;}
template <class T>bool chmin(T &a, const T &b){if(a > b){a = b; return 1;} return 0;}

int main(int argc, char const* argv[])
{
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  string s;
  cin >> s;
  stack<char> st;
  for(int i = 0; i < sz(s); i++){
    if(s[i] == ')'){
      int l = -1, r = -1;
      char o = '+';
      while(true){
        char c = st.top(); st.pop();
        if(c == '(')break;
        if(c >= '0' && c <= '9'){
          if(r >= 0)l = int(c - '0');
          else r = int(c - '0');
        }else{
          o = c;
        }
      }
      int v = l + (o == '+' ? r : - r);
      if(v < 0)st.push('-');
      st.push(char(abs(v) + '0'));
    }else{
      st.push(s[i]);
    }
  }
  vector<char> v;
  while(!st.empty()){
    //cout << st.top() << endl;
    char c = st.top();
    v.pb(c);
    st.pop();
  }
  reverse(all(v));
  int res = 0;
  int curr = 1;
  rep(i, sz(v)){
    if(v[i] >= '0' && v[i] <= '9'){
      res += curr * int(v[i] - '0');
      curr = 1;
    }
    if(v[i] == '-')curr *= -1;
  }
  cout << res << endl;
	return 0;
}