#include <bits/stdc++.h>
using namespace std;

int main() {
    string s;
    cin >> s;
    int absx = 0, absy = 0, signx = 1, signy = 1, op = 0, flag = false;
    for (auto& c : s) {
        if (c >= '0' && c <= '9') {
            ((op ? absy : absx) *= 10) += c - '0';
            flag = true;
        } else {
            int sign = (c == '+' ? 1 : -1);
            if (!flag)
                signx = sign;
            else if (!op)
                op = sign;
            else {
                signy = sign;
            }
        }
    }

    cout << signx * absx - op * signy * absy << endl;
}