#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 n,k;
string s;

int dfs(){
    int ret=0;
    int sgn=1;
    while(1){
        if(k>=n)break;
        if(s[k]==')')break;
        if(s[k]=='('){
            k++;
            ret+=sgn*dfs();
            k++;
        }
        else if(s[k]=='-'){
            sgn=-1;
            k++;
        }
        else if(s[k]=='+'){
            sgn=1;
            k++;
        }
        else {
            int x=s[k]-'0';
            ret+=sgn*x;
            k++;
        }
    }
    return ret;
}
int main(){
    cin>>s;
    n=s.size();
    cout<<dfs()<<endl;
    return 0;
}