/*
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 */
package LinkerList;

/**
 *
 * @author 一天更進步一天
 */
import java.util.Scanner;
import java.util.Stack;

public class InfixToPostfix {

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        while (input.hasNext()) {
            String s = input.nextLine();
            int ans = PostfixCounter(toPostfix(s));
            System.out.println(ans);
        }
    }

    public static String[] toPostfix(String s) { //中序轉後序
 /*
        String data[] = s.split(" ");

        Stack<Character> opst = new Stack<Character>();
        int qReads = 0;
        String[] q = new String[100];

        for (int i = 0; i < data.length; i++) {
        String tmp = data[i];
        if (Character.isDigit(tmp.charAt(0))) {
        q[qReads++] = tmp;
        } else {
        char t = tmp.charAt(0);
        System.out.println(t);
        switch (t) {
        case ')':
        while (opst.peek() != '(') {
        q[qReads++] = opst.pop() + "";
        }
        opst.pop();// pop (
        break;
        case '(':
        opst.push(t);
        break;
        case '+': case '-': case '*': case '/':  case '%':
        if (opst.isEmpty()) {
        opst.push(t);
        } else {
        if (isFormer(t, opst.peek())) {  //如果tmp的優先序大
        opst.push(t);
        } else {
        q[qReads++] = opst.pop() + "";  //放進queue中
        opst.push(t);
        }

        }
        break;
        default:
        System.out.println("errors");

        }
        }

         */

        String data[] = s.split(" ");
        Stack<String> opst = new Stack<String>();
        int qReads = 0;
        String[] q = new String[1000];
        for (int i = 0; i < data.length; i++) {
            if(!data[i].equals("")){
            String tmp = data[i];
            if (isOp(tmp)) {
                if (opst.isEmpty()) {
                    opst.push(tmp);
                } else {
                    if (isFormer(tmp.charAt(0), opst.peek().charAt(0))) {  //如果tmp的優先序大
                        opst.push(tmp);
                    } else {
                        q[qReads++] = opst.pop();  //放進queue中
                        opst.push(tmp);
                    }
                }
            } else if (tmp.equals(")")) {
                while (!opst.peek().equals("(")) {
                    q[qReads++] = opst.pop();
                }
                opst.pop();// pop (
            } else if (tmp.equals("(")) {
                opst.push(tmp);
            } else {
                q[qReads++] = tmp;
            }
            }
        }

        while (!opst.isEmpty()) {
            q[qReads++] = opst.pop() + "";
        }
        /*
        for (String ss : q) {
        System.out.print(ss + ",");
        }*/

        return q;
    }

    public static boolean isOp(String s) {
        /*
        char c = s.charAt(0);
        switch (c) {
            case '+':
            case '-':
            case '*':
            case '/':
            case '%':
                return true;
            default:
                return false;
        }*/
        if(s.equals("+")||s.equals("-")||s.equals("*")||s.equals("/")||s.equals("%")){
            return true;
        }else{
            return false;
        }
    }

    public static boolean isFormer(char a, char b) {   //問a是否比b的次序先?
        boolean isformer = true;
        if (getTheOrder(a) - getTheOrder(b) >= 0) {  //判斷是否不優先(相等當成不優先 )
            //因為由左往後算
            isformer = false;
        }
        return isformer;
    }

    public static int getTheOrder(char c) {//傳回判斷次序先後
        if (c == '+' || c == '-') {//
            return 2;
        } else if (c == '*' || c == '/' || c == '%') {//*/%
            return 1;
        } else {
            return 3;
        }

    }

    public static int PostfixCounter(String data[]) { //or  String[]
        Stack<Integer> st = new Stack<Integer>();

        for (int i = 0; i < data.length; i++) {
            String tmp = data[i];
            if (tmp == null) {
                break;
            } else {
                if (Character.isDigit(tmp.charAt(0))) {
                    st.push(Integer.parseInt(tmp));
                } else {
                    int second = st.pop();
                    int first = st.pop();
                    int sum = countTwoNum(first, tmp.charAt(0), second);
                    st.push(sum);
                }
            }
        }
        return st.peek();
    }

    public static int countTwoNum(int n1, char ind, int n2) {
        //單純的計算兩個數字監的伍則運算
        int ans = 0;
        switch (ind) {
            case '+':
                ans = n1 + n2;
                break;
            case '-':
                ans = n1 - n2;
                break;
            case '*':
                ans = n1 * n2;
                break;
            case '/':
                ans = n1 / n2;
                break;
            case '%':
                ans = n1 % n2;
                break;
            default:
                System.out.println("formate error!!");
                break;
        }
        return ans;
    }
}