import java.io.BufferedReader;
import java.io.InputStreamReader;

public class ArithmeticExpression {

    static int presmetaj(char c[], int l, int r) {
    	int suma=0;
    	if(r-l==4) {
    		int prvbroj=c[l+1]-'0';
    		int vtorbroj=c[r-1]-'0';
    		if(c[l+2]=='+') suma+=(prvbroj+vtorbroj);
    		else if(c[l+2]=='-') suma+=(prvbroj-vtorbroj);
    		return suma;
    	}
    	int brojac=0;
    	for(int i=l;i<=r;i++)
        {
        	if(c[i]=='(')	brojac++;
        	else if(c[i]==')') brojac--;
        	else if(brojac==1&&c[i]=='+') return presmetaj(c,l+1,i-1)+presmetaj(c,i+1,r-1);
        	else if(brojac==1&&c[i]=='-') return presmetaj(c,l+1,i-1)-presmetaj(c,i+1,r-1);
        }
    	return 0;
    }

    public static void main(String[] args) throws Exception {
        int i,j,k;

        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        String expression = br.readLine();
        char exp[] = expression.toCharArray();

        int rez = presmetaj(exp, 0, exp.length-1);
        System.out.println(rez);

        br.close();

    }

}