#include <iostream>
#include <math.h>
#include <algorithm>
#include <string>
#include <stack>
#include <queue>
#include <set>
#include <cstdio>
#include <string.h>
#include <sstream>
#include <iomanip>
#include <map>
using namespace std;

#define REP(i, n) for(int i = 0; i < n; i++)
#define RREP(i, n) for(int i=(n)-1;i>=0;i--)
#define FOR(i, b, e) for(int i = b; i < e; i++)
#define to_bit(i) static_cast< bitset<8> >(i)
#define INF (1<<28)
#define EPS 1e-9

int main(int argc, const char * argv[]){
    //    cout << (int)'+' << endl;
    //    cout << (int)'-' << endl;
    //    cout << (int)'0' << endl;
    string str;
    cin >> str;
    
    FOR(i, 1, str.length()){
        if(str[i-1] >= '0'){
            if(str[i] == '-'){
                str[i] = '+';
            }else if(str[i] == '+'){
                str[i] = '-';
            }
        }
    }
    //    cout << str << endl;
    
    int ans = 0;
    int num = 0;
    int op = 1;
    REP(i,str.length()){
        switch (str[i]) {
            case '+':
                ans += op * num;
                if(num != 0) op = 1;
                num = 0;
                break;
                
            case '-':
                ans += op * num;
                if(num != 0) op = 1;
                num = 0;
                op *= -1;
                break;
                
            default:
                num *= 10;
                num += (int)(str[i] - '0');
                break;
        }
    }
    ans += op * num;
    cout << ans << endl;
}