/* -*- coding: utf-8 -*-
 *
 * 222.cc: No.222 引き算と足し算 - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

/* typedef */

/* global variables */

/* subroutines */

int num(string &s, int &pos) {
  int n = 0, sign = 1;

  if (s[pos] == '+') pos++;
  else if (s[pos] == '-') sign = -1, pos++;

  while (pos < s.size() && s[pos] >= '0' && s[pos] <= '9')
    n = n * 10 + s[pos++] - '0';
  return n * sign;
}

int expr(string &s, int &pos) {
  int e0 = num(s, pos);
  while (pos < s.size()) {
    char op = s[pos++];
    int e1 = num(s, pos);
    if (op == '+') e0 -= e1;
    else e0 += e1;
  }
  return e0;
}

/* main */

int main() {
  string s;
  cin >> s;

  int pos = 0;
  int ans = expr(s, pos);
  printf("%d\n", ans);
  return 0;
}