import java.io.*;
import java.util.*;


public class Main_yukicoder708 {

	private static Scanner sc;
	private static Printer pr;

	private static void solve() {
		char[] s = sc.next().toCharArray();
		int n = s.length;

		Deque<String> q = new ArrayDeque<>();
		q.addLast("0");
		q.addLast("+");
		for (int i = 0; i < n; i++) {
			char c = s[i];
			
			if (c >= '0' && c <= '9') {
				int num = c - '0';
				if (q.peekLast().equals("+")) {
					q.removeLast();
					int tmp = Integer.parseInt(q.removeLast());
					tmp += num;
					q.addLast(Integer.toString(tmp));
				} else if (q.peekLast().equals("-")) {
					q.removeLast();
					int tmp = Integer.parseInt(q.removeLast());
					tmp -= num;
					q.addLast(Integer.toString(tmp));
				} else if (q.peekLast().equals("(")) {
					q.addLast(Integer.toString(num));
				}
			} else if (c == '+') {
				q.addLast("+");
			} else if (c == '-') {
				q.addLast("-");
			} else if (c == '(') {
				q.addLast("(");
			} else if (c == ')') {
				int num = Integer.parseInt(q.removeLast());
				q.removeLast(); // '('
				if (q.peekLast().equals("+")) {
					q.removeLast();
					int tmp = Integer.parseInt(q.removeLast());
					tmp += num;
					q.addLast(Integer.toString(tmp));
				} else if (q.peekLast().equals("-")) {
					q.removeLast();
					int tmp = Integer.parseInt(q.removeLast());
					tmp -= num;
					q.addLast(Integer.toString(tmp));
				}
			}
		}
		
		pr.println(Integer.parseInt(q.peekLast()));
	}

	// ---------------------------------------------------
	public static void main(String[] args) {
		sc = new Scanner(INPUT == null ? System.in : new ByteArrayInputStream(INPUT.getBytes()));
		pr = new Printer(System.out);

		solve();

//		pr.close();
		pr.flush();
//		sc.close();
	}

	static String INPUT = null;

	private static class Printer extends PrintWriter {
		Printer(OutputStream out) {
			super(out);
		}
	}
}