#! /usr/bin/perl

use strict;
use warnings;

my $id = 0;
my $tabCntr;
my %parent;
my $parentId = 0;
$parent{0} = 0;

while (<DATA>) {
	chomp;
	$tabCntr = (s/\t//g || 0);
	$parent{$tabCntr} = ++$id;
	$parentId = $tabCntr?$parent{$tabCntr - 1}:0;
	print "id : $id, name : $_, parent $parentId \n";
}	

__END__
cat1
	cat1,sub1
		cat1,sub1,sub-sub1
		cat1,sub1,sub-sub1
			cat1,sub2
cat2
cat3
	cat3,sub1