import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        StringBuilder sb = new StringBuilder(s);
        for(int i = 0; i < sb.length(); ++i){
            if(sb.charAt(i) == '-'){//在所有‘-’号前添个加号
                sb.insert(i, '+');//减法统一为负数加法
                ++i;
            }
        }
        String[] v = String.valueOf(sb).split("[+]");//按加号断开,累加就行了
        int sum = 0;
        for(int i = 0; i < v.length; ++i) {
            if(!v[i].equals(""))sum += Integer.valueOf(v[i]);
        }
        System.out.println(sum);
    }
}