#include <bits/stdc++.h>
using namespace std;
inline int read() {
  char ch = getchar();
  int x = 0, f = 1;
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    x = x * 10 + ch - '0';
    ch = getchar();
  }
  return x * f;
}
char a[100];
int len;
long long res = 0, cur = 0;
int sign = 1;
int main() {
  scanf("%s", a);
  len = strlen(a);
  for (int i = 0; i < len; i++) {
    if (a[i] == '-' || a[i] == '+') {
      res += sign * cur;
      cur = 0;
    }
    if (a[i] == '-') {
      sign = -1;
    }
    if (a[i] == '+') {
      sign = 1;
    }
    cur = cur * 10 + a[i] - '0';
  }
  res += sign * cur;
  printf("%lld", res);
  return 0;
}
