#include<bits/stdc++.h>
using namespace std;
string n;
int a[1005],sum;
char b[1005];
int main()
{
	
  cin>>n;
	for(int i=0;i<n.size();i++)
	{
		if(n[i]>='1' && n[i]<='9')
		{
			sum+=int(n[i]-'0');
			//cout<<sum<<endl;
		}
		else
		{
			if(n[i]=='+'){
				sum+=int(n[i+1]-'0');
				i++;
				//cout<<sum<<endl;
			}
			else{
				sum-=int(n[i+1]-'0');
				i++;
				//cout<<sum<<endl;
			}
		}
	}
	
	cout<<sum;
	return 0;
}