#include <iostream>
#include <string>
#include <string.h>
#include <vector>
#include <algorithm>
#include <sstream>
#include <set>
#include <queue>
#include <tuple>

using namespace std;

#define For(i,a,n)	for(int i = a;i < n;i++)
#define rep(i,n)	For(i,0,n)
#define clr(n)		memset(n,0,sizeof n)
#define all(n)		(n).begin(),(n).end()

typedef pair<int, int> P;
typedef tuple<int, int, int> T;
typedef long long ll;

const ll INF = 1e9;
int dx[4] = { 0, 1, 0, -1 }, dy[4] = { 1, 0, -1, 0 };
bool cheak(int x, int y, int mx, int my){
	return x >= 0 && y >= 0 && x < mx &&  y < my;
}

int c = 0;
string s;

int solve(){

	int ret = 0;

	if (s[c] >= '0' && s[c] <= '9'){
		string t;
		while (s[c] >= '0' && s[c] <= '9'){
			t += s[c];
			c++;
		}
		ret = atoi(t.c_str());
	}else
	if (s[c] == '-'){
		c++;
		ret -= solve();
	}else
	if (s[c] == '+'){
		c++;
		ret += solve();
	}

	return ret;
}


int main()
{
	cin >> s;
	s += "\\";
	int x = solve();
	bool f = (s[c] == '+'); c++;
	int y = solve();
	int ans = 0;
	if (f){
		ans = x - y;
	}
	else{
		ans = x + y;
	}

	cout << ans << endl;
	return 0;
}