Beleg/taschenrechn...

def Grundrechenarten(c,a,d):

    if a == '+':
        result = float(c)+float(d)
    elif a == '-':
        result = float(c)-float(d)
    elif a == '*':
        result = float(c)*float(d)
    elif a == '/':
        result = float(c)/float(d)

    if result == int(result):
        result = int(result)

    return result

def toList(s):

    L = []
    for i in s:
        if i != '\n':
            L.append(i)
    return L

def f(i,s,S = None):

    if not S:
        S = []
        
    if i == len(s):
        return S[0]

    a = s[i]
    if a.isdigit():
        S.append(a)
        return f(i+1,s,S)
    else:
        c = S.pop()
        d = S.pop()
        
        S.append(Grundrechenarten(c,a,d))
        return f(i+1,s,S)


x = raw_input()
s = ""
while x != '=\n':
    s += x
    x = raw_input() + '\n'


print f(0,toList(s))