Method calculate

tutorial/cpp/CppServer.cpp:58–95

  }

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

    switch (work.op) {
    case Operation::ADD:
      val = work.num1 + work.num2;
      break;
    case Operation::SUBTRACT:
      val = work.num1 - work.num2;
      break;
    case Operation::MULTIPLY:
      val = work.num1 * work.num2;
      break;
    case Operation::DIVIDE:
      if (work.num2 == 0) {
        InvalidOperation io;
        io.whatOp = work.op;
        io.why = "Cannot divide by 0";
        throw io;
      }
      val = work.num1 / work.num2;
      break;
    default:
      InvalidOperation io;
      io.whatOp = work.op;
      io.why = "Invalid Operation";
      throw io;
    }

    SharedStruct ss;
    ss.key = logid;
    ss.value = to_string(val);

    log[logid] = ss;

    return val;
  }

  void getStruct(SharedStruct& ret, const int32_t logid) override {
    cout << "getStruct(" << logid << ")" << '\n';