#include<bits/stdc++.h>
using namespace std;
#define int long long
signed main() {
	string s;cin>>s;
	int first=0;
	int i=0;
	int k=1;
	if(s[0]=='+') {
		i=1;
	}
	if(s[0]=='-') {
		i=1;
		k=-1;
	}
	while(i<s.size()&&s[i]>='0'&&s[i]<='9') {
		first=first*10+s[i]-'0';
		i++;
	}
	first*=k;
	while(i<s.size()) {
		int j = i+1;
		int now=0;
		while(j<s.size()&&s[j]>='0'&&s[j]<='9') {
			now=now*10+s[j]-'0';
			j++;
		} 
		if(s[i]=='+') first+=now;
		else first-=now;
		i=j;
	}
	cout<<first<<endl;
	return 0;
}