my $s='helloworldhellohellohihellohiworld';

#determine every substring in the original
my %hash;
for my $i (0..length($s)-1) {
	$hash{substr($s,$i,$_)}++
		for (1..length($s)-$i);
}
#filter out singles and the chars
%hash=map {
           ($hash{$_}>1 && length($_)>1)
            ? ($_,$hash{$_})
            :()
          } keys %hash; #yes this is how i format maps
                        #and ternary ops.. :-)
#print the results
use Data::Dumper;
print Dumper(\%hash);