int main(int argc, char **argv) {
  if (argc != 3) {
    return ERROR_PARAMETER_INVALID;
  }

  try {
    std::string element;
    std::stack<LN> numbers;
    std::ifstream in(argv[1]);
    std::ofstream out(argv[2]);
    if (in.bad() || in.fail() || out.bad() || out.fail()) {
      return ERROR_CANNOT_OPEN_FILE;
    }
    while (in >> element) {
      if (element == "+") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 + n2; });
      } else if (element == "-") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 - n2; });
      } else if (element == "/") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 / n2; });
      } else if (element == "*") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 * n2; });
      } else if (element == "%") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 % n2; });
      } else if (element == "!=") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 != n2; });
      } else if (element == "==") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 == n2; });
      } else if (element == ">=") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 >= n2; });
      } else if (element == "<=") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 <= n2; });
      } else if (element == "<") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 < n2; });
      } else if (element == ">") {
        ExecuteBinary(numbers,
                      [](const auto &n1, const auto &n2) { return n1 > n2; });
      } else if (element == "_") {
        ExecuteUnary(numbers, [](const auto &n) { return -n; });
      } else if (element == "~") {
        ExecuteUnary(numbers, [](const auto &n) { return ~n; });
      } else {
        numbers.emplace(element);
        if (numbers.top().IsNaN()) {
          return ERROR_DATA_INVALID;
        }
      }
    }

    while (!numbers.empty()) {
      out << numbers.top().ToString() << std::endl;
      numbers.pop();
    }
  } catch (const std::bad_alloc &) {
    return ERROR_OUT_OF_MEMORY;
  } catch (const std::domain_error &) {
    return ERROR_DATA_INVALID;
  } catch (...) {
    return ERROR_UNKNOWN;
  }
  return SUCCESS;
}