#!/usr/bin/env python
# -*- coding: utf-8 -*-
# rpn.py
# 逆ポーランド記法を使った電卓プログラム

import string

stack = []

while 1:
    x = raw_input('? ')
    if x == '+':
        stack.append(stack.pop() + stack.pop())
    elif x == '-':
        stack.append(stack.pop(-2) - stack.pop())
    elif x == '*':
        stack.append(stack.pop() * stack.pop())
    elif x == '/':
        stack.append(stack.pop(-2) / stack.pop())
    else:
        stack.append(string.atof(x))
    print stack,