#!/usr/bin/perl
  
  my $filtRes="";
  my %keywords;
  
  while(<STDIN>){
  	chomp($_);
  	my $word = $_;
  		
      if(! exists $keywords{$word}){
  	    $filtRes .= "$word+";
  		$keywords{$word}++;
      }
  }
  # test si la query est non vide
  if($filtRes !~ /^\s*$/){
      $filtRes =~ s/\+$//g;
      print "$filtRes
  ";
  }