#!/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\n";
}