#include <bits/stdc++.h>
using namespace std;
string s;
long long sum;
int main()
{
	cin>>s;
	sum=s[0]-'0';
	for(int i=1;i<s.size();i++)
	{
		if(s[i]=='+') sum+=s[i+1]-'0';
		if(s[i]=='-') sum-=s[i+1]-'0';
	}
	cout<<sum;
	return 0;
}