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

public class Calculator {
    private Stack stack;
    
    Calculator () {
        stack = new Stack();
        
    }
    
    
    
    public void processInput (String input) {
        int value = 0;
        if (input.equals("+")) {
            // fill in here
        } else if (input.equals("*")) {
            // fill in here
        } else {
           // need to convert string to int here
            value = Integer.parseInt(input);
             stack.push(new Integer(value));
            System.out.println(stack.pop());
        }
        
    }
    
    public static void main(String[] arg) throws Exception {
        // this is code to take input from the keyboard
        Calculator calc = new Calculator();
                InputStreamReader isr;
                BufferedReader keyboard;
                String inputLine;
                isr = new InputStreamReader(System.in);
                keyboard = new BufferedReader(isr);
                
                // put in a loop here to read input until done
                // you will need to also check for an input meaning end
                // this is an example of the input call you will make
                // within the loop
                
                    inputLine = keyboard.readLine();
                    calc.processInput(inputLine);
                    
                
                
               
               // put in code to call the calculator methods here.
    }
}