#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define llong long long

int calc(char op, int ee, int er) {
    if(op == '+') return ee + er;
    return ee - er;
}

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

    int ee = 0;
    int er = 0;
    char op = '+';
    char opbr = '+';
    bool inbracket = false;
    for(char c: s) {
        switch(c) {
            case '+':
            case '-':
                if(inbracket) opbr = c;
                else op = c;
                break;
            case '(':
                inbracket = true;
                break;
            case ')':
                inbracket = false;
                ee = calc(op, ee, er);
                er = 0;
                opbr = '+';
                break;
            default:
                if(inbracket) er = calc(opbr, er, stoi(""s + c));
                else ee = calc(op, ee, stoi(""s + c));
                break;
        }
    }
    cout << ee << "\n";
}