use XML::Rules;
my %results;
my $parser=XML::Rules->new(
  rules => [
    tc => sub {
      $results{ $_[1]->{result} }++;
      return
    },
    _default => '',
  ],
);
$parser->parse($conf);

foreach my $result (sort keys %results) {
  print "$result: $results{$result}\n";
}
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Why build a structure containing all the data from the XML if all you want to know are the counts of the different result attributes of the <tc> tag?