#include <bits/stdc++.h>
using namespace std;
#define fastcin {\
    cin.tie(0);\
    ios::sync_with_stdio(false);\
}
#define rep(i, a, b) for(int i = a; i < b; i++)
#define rrep(i, a, b) for(int i = a; i >= b; i--)
typedef vector<int> vi;

int main() {
    fastcin;
    string s;
    cin >> s;
    int ans = 0;
    int k = 1, b = 1;
    rep(i, 0, s.length()) {
        char c = s[i];
        if(c>=0+'0' && c<=9+'0') {
            ans += k*b*(c-'0');
        } else if(c=='+') b = 1;
        else if(c=='-') b = -1;
        else if(c=='(') {
            k = b;
            b = 1;
        }
        else if(c==')') k = 1;
    }
    cout << ans << endl;
}