#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <regex>

#define FORR(i,b,e) for(int i=(b);i<(int)(e);++i)
#define FOR(i,e) FORR(i,0,e)
#define sortuniq(v) sort(v.begin(), v.end()), v.erase(unique(v.begin(),v.end()),v.end())
#define dump(var) cerr << #var ": " << var << "\n"
#define dumpc(con) for(auto& e: con) cerr << e << " "; cerr<<"\n"

typedef long long ll;
typedef unsigned long long ull;

const double EPS = 1e-6;
const int d4[] = {0, -1, 0, 1, 0};

using namespace std;

int str_to_int(const string &s) {
    istringstream buf(s);
    int v;
    buf >> v;
    return v;
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);

    string exp;
    cin >> exp;

    regex re("([+\\-]?)([0-9]+)([+\\-])([+\\-]?)([0-9]+)");
    smatch m;

    if (regex_match(exp, m, re)) {
        int x = str_to_int(m[2].str()), y = str_to_int(m[5].str());
        if (m[1] == "-") x *= -1;
        if (m[4] == "-") y *= -1;
        cout << (m[3]=="-"? x+y: x-y) << endl;
    }

    return 0;
}