ros::init(argc,argv,"topic_pub");

ros::NodeHandle nh;

ros::Publisher flag_pub = nh.advertise<std_msgs::Bool>("flag",10);

ros::Rate loop_rate(10);

int count =0;

while(ros::ok()){

std_msgs::Bool flag_msg;

flag_msg.data = false;

if(count>=10){

count=0;

flag_msg.data = true;

}

flag_pub.publish(flag_msg);

ros::spinOnce();

loop_rate.sleep();

++count;

}

return 0;