#include <iostream>
#include <string>
using namespace std;
int main() {
string input;
cin >> input;
int result = 0;
string num;
bool isMinus = false;
for (int i = 0; i <= input.size(); i++) {
if (input[i] == '-' || input[i] == '+' || i == input.size())
{
if (isMinus) {
result -= stoi(num);
num = "";
}
else {
result += stoi(num);
num = "";
}
}
else {
num += input[i];
}
if (input[i] == '-') {
isMinus = true;
}
}
cout << result;
}