Return array in service in c++

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Hi people! I'm starting with ROS and I have a problem implementing a client and server. I used the files created in the tutorials of ROS but I would like to return an array of strings and I don't know how to do it. These are my codes:

get_element_server.cpp:

#include "ros/ros.h"
#include "beginner_tutorials/GetElement.h"

bool add(beginner_tutorials::GetElement::Request  &req,
         beginner_tutorials::GetElement::Response &res)
{
  res.result = {"table", "chair"};
  ROS_INFO("request: x=%s", req.name.c_str());
  ROS_INFO("sending back response: [%s] [%s]", res.result[0].c_str(), res.result[1].c_str());
  return true;
}

int main(int argc, char **argv)
{
  ros::init(argc, argv, "get_element_server");
  ros::NodeHandle n;

  ros::ServiceServer service = n.advertiseService("get_element", add);
  ROS_INFO("Ready to get element.");
  ros::spin();

  return 0;
}

get_element_client.cpp:

#include "ros/ros.h"
#include "beginner_tutorials/GetElement.h"
#include <cstdlib>

int main(int argc, char **argv)
{
  ros::init(argc, argv, "get_element_client");
  if (argc != 2)
  {
    ROS_INFO("usage: get_element_client name");
    return 1;
  }

  ros::NodeHandle n;
  ros::ServiceClient client = n.serviceClient<beginner_tutorials::GetElement>("get_element");
  beginner_tutorials::GetElement srv;
  srv.request.name = argv[1];
  if (client.call(srv))
  {
    ROS_INFO("Elements: %s, %s", srv.response.result[0].c_str(), srv.response.result[1].c_str());
  }
  else
  {
    ROS_ERROR("Failed to call service get_element");
    return 1;
  }

  return 0;
}

GetElement.h

string name
---
string[] result

The error that I obtain is the following when I use 'catkin_make':

/home/javier/catkin_ws/src/beginner_tutorials/src/get_element_server.cpp: In function ‘bool add(beginner_tutorials::GetElement::Request&, beginner_tutorials::GetElement::Response&)’:
/home/javier/catkin_ws/src/beginner_tutorials/src/get_element_server.cpp:7:7: error: ‘beginner_tutorials::GetElement::Response’ has no member named ‘result’
   res.result = {"table", "chair"};
       ^
/home/javier/catkin_ws/src/beginner_tutorials/src/get_element_server.cpp:7:33: warning: extended initializer lists only available with -std=c++11 or -std=gnu++11 [enabled by default]
   res.result = {"table", "chair"};
                                 ^
In file included from /opt/ros/indigo/include/ros/ros.h:40:0,
                 from /home/javier/catkin_ws/src/beginner_tutorials/src/get_element_server.cpp:1:
/home/javier/catkin_ws/src/beginner_tutorials/src/get_element_server.cpp:8:33: error: ‘beginner_tutorials::GetElement::Request’ has no member named ‘name’
   ROS_INFO("request: x=%s", req.name.c_str());
                                 ^
/opt/ros/indigo/include/ros/console.h:342:165: note: in definition of macro ‘ROSCONSOLE_PRINT_AT_LOCATION_WITH_FILTER’
     ::ros::console::print(filter, __rosconsole_define_location__loc.logger_, __rosconsole_define_location__loc.level_, __FILE__, __LINE__, __ROSCONSOLE_FUNCTION__, __VA_ARGS__)
                                                                                                                                                                     ^
/opt/ros/indigo/include/ros/console.h:375:7: note: in expansion of macro ‘ROSCONSOLE_PRINT_AT_LOCATION’
       ROSCONSOLE_PRINT_AT_LOCATION(__VA_ARGS__); \
       ^
/opt/ros/indigo/include/ros/console.h:557:35: note: in expansion of macro ‘ROS_LOG_COND’
 #define ROS_LOG(level, name, ...) ROS_LOG_COND(true, level, name, __VA_ARGS__)
                                   ^
/opt/ros/indigo/include/rosconsole/macros_generated.h:110:23: note: in expansion of macro ‘ROS_LOG’
 #define ROS_INFO(...) ROS_LOG(::ros::console::levels::Info, ROSCONSOLE_DEFAULT_NAME, __VA_ARGS__)
                       ^
/home/javier/catkin_ws/src/beginner_tutorials/src/get_element_server.cpp:8:3: note: in expansion of macro ‘ROS_INFO’
   ROS_INFO("request: x=%s", req.name.c_str());
   ^
/home/javier/catkin_ws/src/beginner_tutorials/src/get_element_server.cpp:9:52: error: ‘beginner_tutorials::GetElement::Response’ has no member named ‘result’
   ROS_INFO("sending back response: [%s] [%s]", res.result[0].c_str(), res.result[1].c_str());
                                                    ^
/opt/ros/indigo/include/ros/console ...