#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<cctype>
#include<cstdlib>
#include<algorithm>
#include<bitset>
#include<vector>
#include<list>
#include<deque>
#include<queue>
#include<map>
#include<set>
#include<stack>
#include<cmath>
#include<sstream>
#include<fstream>
#include<iomanip>
#include<ctime>
#include<complex>
#include<functional>
#include<climits>
#include<cassert>
#include<iterator>
using namespace std;
string s;
int main(){
	cin >> s;
	stringstream ss;
	ss << s;
	long long int k;
	ss >> k;
	long long int kari = 0;
	char op;
	while (ss >> op){
		ss >> kari;
		if (op == '-'){
			k += kari;
		}
		else{
			k -= kari;
		}
	}
	printf("%lld\n", k);
	return 0;
}