#include <iostream>
#include <stack>
#include <string>
#include <vector>
#include <sstream>

using namespace std;

float processStack(stack<string> &s);
bool isOperator(string str);

template <class T>
T fromString(string x)
{
    T retval;
    istringstream strin(x);
    strin >> retval;
    return retval;
}

template <class T>
string toString(T x)
{
    ostringstream strout;
    strout << x;
    return strout.str();
}

void prompt()
{
    cout << ">> ";
}

vector<string> split(string line, string separator)
{
    vector<string> retval;
    char * cstr, * p;
    cstr = new char [line.size() + 1];
    strcpy(cstr, line.c_str());
    p = strtok(cstr, separator.c_str());
    while (p != NULL) {
        retval.push_back(p);
        p = strtok(NULL, separator.c_str());
    }
    delete cstr;
    return retval;
}

bool isOperator(string str)
{
    string operators [] = {"+", "-", "*", "/"};
    for (int i = 0; i < 4; i++) {
        if (str == operators[i]) return true;
    }
    return false;
}

float processStack(stack<string> &s)
{
    string str("");
    if (!s.empty()) {
        str = s.top(); s.pop();
        if (!isOperator(str)) {
            return fromString<int>(str);
        }
        else {
            string stra = s.top();
            float ia = 0.0;
            if (isOperator(stra)) ia = processStack(s);
            else {
                ia = fromString<float>(stra);
                s.pop();
            }

            string strb = s.top();
            float ib = 0.0;
            if (isOperator(strb)) ib = processStack(s);
            else {
                ib = fromString<float>(strb);
                s.pop();
            }
            if (str == "+") {
                return ia + ib;
            }
            else if (str == "-") {
                return ia - ib;
            }
            else if (str == "*") {
                return ia * ib;
            }
            else if (str == "/") {
                return ia / ib;
            }
        }
    }
    return 0;
}

int main (int argc, char *argv[])
{
    stack<string> s;
    char buff [8126];
    prompt();
    while (cin.good() && cin.getline(buff, 8126)) {
        string line(buff);
        if (line == "bye") return 0;
        vector<string> tokens = split(line, " ");
        for (size_t i = 0; i < tokens.size(); i++) {
            s.push(tokens[i]);
        }
        cout << "result: " + toString<float>(processStack(s)) << endl;
        prompt();
    }
    return 0;
}