Method add

tutorial/cpp/CppServer.cpp:53–56

  void ping() override { cout << "ping()" << '\n'; }

  int32_t add(const int32_t n1, const int32_t n2) override {
    cout << "add(" << n1 << ", " << n2 << ")" << '\n';
    return n1 + n2;
  }

  int32_t calculate(const int32_t logid, const Work& work) override {
    cout << "calculate(" << logid << ", " << work << ")" << '\n';