#!/opt/bin/perl

use Switch;
use 5.010;

my %is_ready = ('teacher' => "student",  'student' => "teacher");


for(%is_ready){
    
	given($_) {
	
	    when(/student/) { appear($is_ready{$_}); }
	
	    when(/teacher/) { appear($is_ready{$_}); }
	
	}
	
}


sub appear{
  $appear = shift;
  print "$appear is ready, ". $is_ready{$appear} ."\n";
}