subscriber and if-else/switch-case statement [closed]

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Hi there, I am new to ROS and having a bit of problems when using subscriber. I am writing a leader following function and trying to subscribe to a rostopic under a conditional statement, switch statement in this case, but it doesn't work. Key lines of the problem are shown below:

main(int argc, char **argv)
{
  ros::init(argc, argv, "mycontrol_1");

  ros::NodeHandle n;

  ros::Subscriber h_sub = n.subscribe("/uav1/sonar_height",1000,hcontrol);

  switch (squad_leader_no){

    case 1:

      {ros::Subscriber splitcmd_sub = n.subscribe("/uav1/split_cmd", 1000, getsplitcmd);

      break;}

    case 2:

      {ros::Subscriber splitcmd_sub = n.subscribe("/uav2/split_cmd", 1000, getsplitcmd);

      break;}

    case 3:

      {ros::Subscriber splitcmd_sub = n.subscribe("/uav3/split_cmd", 1000, getsplitcmd);

      break;}

    case 4:

      {ros::Subscriber splitcmd_sub = n.subscribe("/uav4/split_cmd", 1000, getsplitcmd);

      break;}

  }

...

  // loop rate of 35Hz

  ros::Rate cycle(35);

...

In above case, subscription fails. But when I pull the subscriber out of the conditional statement, it subscribe successfully. Could anybody be helpful on this problem if know why, please? Thanks in advance.