import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Arrays;

public class ArithmeticExpression {


    public static int presmetaj(char c[], int l, int r) {

    	if (r - l == 4){

    		return valueOfNode(c, l+1, r-1);
    	}

    	int posOfSign = splitExpression (c, l, r);
    	if (c[posOfSign] == '+'){

    		return presmetaj(c, l+1, posOfSign-1) + presmetaj (c, posOfSign+1, r-1);
    	}
    	else {
    		return presmetaj(c, l+1, posOfSign-1) - presmetaj (c, posOfSign+1, r-1);
    	}

    }

    public static int splitExpression (char[] c, int l, int r){
    	int numberOfParenthesis = 0;
    	for (int i = l; i<=r; i++) {
    		if (c[i] == '('){
    			numberOfParenthesis++;
    		}
    		else if (c[i] == ')'){
    			numberOfParenthesis--;
    		}
    		else if(c[i] == '+' || c[i] == '-'){
                if(numberOfParenthesis == 1)
                        return i;
    		}
    	}

    	return 0;

    }

    public static int valueOfNode (char[] c, int l, int r){

    	int num1 = Integer.valueOf(String.valueOf(c[l]));
    	int num2 = Integer.valueOf(String.valueOf(c[r]));

    	if (c[l+1] == '+'){
    		return num1 + num2;
    	}
    	else {
    		return num1 - num2;
    	}


    }



    public static void main(String[] args) throws Exception {

        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();

    }

}