# Copyright (C) 2009 Andreas Bolka
# See http://factorcode.org/license.txt for BSD license.
import operator

def mk_push(token):
    return lambda stack: push_insn(stack, int(token))

def binary_op(stack, op):
    stack.append(op(stack.pop(), stack.pop())); return stack

def add_insn(stack): return binary_op(stack, operator.add)
def sub_insn(stack): return binary_op(stack, operator.sub)
def mul_insn(stack): return binary_op(stack, operator.mul)
def div_insn(stack): return binary_op(stack, operator.div)
def push_insn(stack, value): stack.append(value); return stack

def eval_insn(stack, fn):
    return fn(stack)

def rpn_tokenize(string):
    return string.split()

def rpn_parse(string):
    return map(lambda token: {'+': add_insn,
                              '-': sub_insn,
                              '*': mul_insn,
                              '/': div_insn}.get(token, mk_push(token)),
               rpn_tokenize(string))

def print_stack(stack):
    for item in stack: print item

def rpn_eval(tokens):
    print_stack(reduce(eval_insn, tokens, []))

def rpn():
    try:
        while True: rpn_eval(rpn_parse(raw_input('RPN> ')))
    except EOFError:
        pass