G'day audioboxer,
Purely as a fun exercise, I put this together before studying other offerings.
There's a few similarities with other posts.
#!/usr/bin/env perl
use strict;
use warnings;
use constant {
CHILD_ID => 0,
CAT_NAME => 1,
};
my $VAR1 = {
986172 => { cat_parent_id => '', cat_name => 'Category1' },
986178 => { cat_parent_id => '986177', cat_name => 'Category4' },
986177 => { cat_parent_id => '986176', cat_name => 'Category3' },
986176 => { cat_name => 'Category2', cat_parent_id => '986172' }
};
my $wanted_string = get_wanted_string($VAR1);
print "$wanted_string\n";
sub get_wanted_string {
my ($data) = @_;
my (%family, @cats);
for my $child_id (keys %$data) {
my ($parent_id, $cat_name)
= @{$data->{$child_id}}{qw{cat_parent_id cat_name}};
$family{$parent_id} = [$child_id, $cat_name];
}
return join ',', @{recurse_family(\%family, \@cats)};
}
sub recurse_family {
my ($family, $cats, $parent) = @_;
$parent = '' unless defined $parent;
return $cats unless exists $family->{$parent};
push @$cats, $family->{$parent}[CAT_NAME];
recurse_family($family, $cats, $family->{$parent}[CHILD_ID]);
}
Output:
Category1,Category2,Category3,Category4