//求形如1+4-5+4-9...算式字符串的值
import java.util.Scanner;
public class Main {
public static int calcu(String s){
char a[]=s.toCharArray();
boolean flag=true;
int x=0,ans=0;
for(int i=0;i<a.length;i++){
if(a[i]=='+'||a[i]=='-'){
if(flag) ans+=x;
else ans-=x;
if(a[i]=='+') flag=true;
else flag=false;
x=0;
}
else{
x=x*10+a[i]-'0';
}
}
if(flag) ans+=x;
else ans-=x;
return ans;
}
public static void main(String[] args) {
Scanner scan=new Scanner(System.in);
String s=scan.next();
System.out.println(calcu(s));
}
}