sub Prioritise_requests {

  my ($input_directory) = @_;

  my $input_directory_lowest = $input_directory."1";
  my $input_directory_highest = $input_directory."2";


  readdir (LOWEST, "<$input_directory_lowest") or die "Error opening directory: $!";
  readdir (HIGHEST, "<$input_directory_highest") or die "Error opening directory: $!";

  my @lowest_priority = <LOWEST>;

  my $request_of_interest = 'none';


  foreach (@lowest_priority){    # foreach low priority request

    my @highest_priority = <HIGHEST>; # fill high_priority array

    if (@highest_priority) {  #  If there are elements in the array 
      #Do nothing
    }
    else {
      $request_of_interest = $_;
    }


    if (@highest_priority) {
      foreach (@highest_priority){   # foreach high priority request
	$request_of_interest = $_;
	return  $request_of_interest;
      }
    }
    return  $request_of_interest;
  }
}