using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static string[] SList(long n) => Enumerable.Repeat(0, (int)n).Select(_ => ReadLine()).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var s = ReadLine();
        WriteLine(Calc(s));
    }
    static int Calc(string s)
    {
        var ans = 0;
        for (var i = 0; i < s.Length; ++i)
        {
            var flg = true;
            if (s[i] == '+' || s[i] == '-')
            {
                if (s[i] == '-') flg = false;
                ++i;
            }
            if (s[i] >= '0' && s[i] <= '9')
            {
                ans += (s[i] - '0') * (flg ? 1 : -1);
            }
            if (s[i] == '(')
            {
                var end = i + 1;
                for (; end < s.Length; ++end) if (s[end] == ')') break;
                var inner = Calc(s[(i+1)..end]);
                ans += flg ? inner : -inner;
                i = end;
            }
        }
        return ans;
    }
}