/* Copyright (C) 2015 by Alexandru Cojocaru */

/* This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>. */

// try:
//   echo '19 2.14 + 4.5 2 4.3 / - *' | go run 1.go

package main

import (
	"bufio"
	"fmt"
	"log"
	"os"
	"strconv"
)

var stack []float64

func push(n float64) {
	stack = append(stack, n)
}

func pop() float64 {
	n := stack[len(stack)-1]
	stack = stack[:len(stack)-1]
	return n
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Split(bufio.ScanWords)
	for scanner.Scan() {
		str := scanner.Text()
		switch str {
		case "+":
			push(pop() + pop())
		case "-":
			push(-pop() + pop())
		case "*":
			push(pop() * pop())
		case "/":
			push(1 / pop() * pop())
		default:
			n, err := strconv.ParseFloat(str, 64)
			if err != nil {
				log.Fatal(err)
			}
			push(n)
		}
	}
	if err := scanner.Err(); err != nil {
		log.Fatal(err)
	}
	fmt.Printf("%v\n", stack)
}