import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int ans = 0;
        int tmp = 0;
        boolean isPlus = true;
        for (char c : sc.next().toCharArray()) {
            if (c == '+' || c == '-') {
                if (isPlus) {
                    ans += tmp;
                } else {
                    ans -= tmp;
                }
                tmp = 0;
                isPlus = (c == '-');
            } else {
                tmp *= 10;
                tmp += c - '0';
            }
        }
        if (isPlus) {
            ans += tmp;
        } else {
            ans -= tmp;
        }
        System.out.println(ans);
    }
}
class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
}