#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
using ll = long long;

int f(string& s) {
    int n = s.size();
    int sgn = 1;
    int r = 0;
    for (int i = 0; i < n; i++) {
        if (s[i] == '(') {
            int j = i;
            while (s[j] != ')') j++;
            string t = s.substr(i + 1, j - i - 1);
            r += f(t) * sgn;
            i = j;
        } else if (s[i] == '+') {
            sgn = 1;
        } else if (s[i] == '-') {
            sgn = -1;
        } else {
            r += (s[i] - '0') * sgn;
        }
    }
    return r;
}

int main() {
    string s;
    cin >> s;

    cout << f(s) << endl;

    return 0;
}