#include<iostream>
#include<string>
#include<algorithm>
#include<vector>
#include<iomanip>
#include<math.h>
#include<complex>
#include<queue>
#include<deque>
#include<map>
#include<set>
#include<bitset>
using namespace std;
#define REP(i,m,n) for(int i=(int)m ; i < (int) n ; i++ )
#define rep(i,n) REP(i,0,n)
typedef long long ll;
typedef pair<int,int> pint;
const int inf=1e9+7;
const ll longinf=1LL<<60 ;
const ll mod=998244353 ;
int dx[4]={1,0,-1,0} , dy[4]={0,1,0,-1} ;

int sum(string s,int& i);
int bracket(string s,int& i);

int sum(string s,int& i){
    int ret=bracket(s,i);
    while(s[i]=='+'||s[i]=='-'){
        char op=s[i];
        i++;
        int res=bracket(s,i);
        if(op=='+')ret+=res;
        else ret-=res;
    }
    return ret;
}

int bracket(string s,int& i){
    int ret;
    int x=s[i]-'0';
    if(0<=x&&x<=9)ret=x;
    else{
        i++;
        ret=sum(s,i);
        }
    i++;
    return ret;
}

int main(){
    string s;
    cin>>s;
    int i=0;
    cout<<sum(s,i)<<endl;
}