Parrameter server in C++ publisher?

edit

How do i provide command line parameter for publisher written in c++. I tried similar to what i did with python publisher but it doesn't work. I used getparam in c++.

#include "ros/ros.h"
#include "performance_tests/SuperAwesome.h"  
#include <sstream>

int main(int argc, char **argv)
{
ros::init(argc, argv, "PublisherNode");
ros::NodeHandle nh;
std::string ra; //I want to accept an Integer value
if (nh.getParam("/ra", ra))
    {

      ROS_INFO("Got param: %s", ra.c_str());
    }
else
    {
      ROS_INFO("Failed to get param ");

    }
ros::Publisher msg_pub = nh.advertise<performance_tests::SuperAwesome>("publisher", 1000);
// I want to change the rate value through the value I receive in through ra.
ros::Rate rate(100);

int count = 0;

while (ros::ok())
{
    performance_tests::SuperAwesome msg;
    std::stringstream s;

    s <<"Hello World " << count; 
    msg.data = s.str();

    ROS_INFO("%s",msg.data.c_str());
    msg_pub.publish(msg);
    ros::spinOnce();

    rate.sleep();

    count++;
}

return 0;
}

I would like to change the publisher rate through command line parameter similar to what I do in python publisher. i.e,

rosrun publisher_package publisher.py _rate:=50

How can I do the same in c++ publisher