#include<bits/stdc++.h>
using namespace std;
int main(){
	string s;
	cin>>s;
	int l=s.length(),sum=0;
	for(int i=l;i>0;i--){
		if(s[i]=='+'&&isdigit(s[i-1])){
			sum=sum+s[i-1];
		}
		if(s[i]=='+'&&isdigit(s[i-2])){
			sum=sum+(s[i-1])*10+s[i-2];
		}
		if(s[i]=='-'&&isdigit(s[i-1])){
			sum=sum-s[i-1];
		}
		if(s[i]=='-'&&isdigit(s[i-2])){
			sum=sum-s[i-1]+(s[i-2])*10;
		}
		else
			i--;
	}
	cout<<sum<<endl;
	return 0;
}