using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Text;
using System.Text.RegularExpressions;
using System.Linq;

class Magatro
{

    static void Main()
    {
        string S = Console.ReadLine();
        S = S.Replace("--", "+");
        S = S.Replace("+-", "-");
        int[] a = new int[2];
        int c = 0;
        string SS = "";
        for(int i =0; i<S.Length; i++)
        {
            if (S[i] == '+')
            {
                a[c] = int.Parse(SS);
                c++;
                SS = "";
                continue;
            }
            else if(S[i]=='-')
            {
                if (SS != "")
                {
                    a[c] = int.Parse(SS);
                    c++;
                    SS = "";
                }
            }
            SS += S[i];
        }
        a[1] = -int.Parse(SS);
        Console.WriteLine(a[1] + a[0]);
    }
}
enum T
{
    plus,minus
}