#!/usr/bin/perl
use warnings;
use strict;

use Data::Diver qw{ DiveRef };
use Data::Dumper;

my $hash = {};
my @path;
while (<DATA>) {
    chomp;
    s/^(\t*)//;
    my $depth = length $1;
    splice @path, $depth + 1;
    $path[$depth] = $_;
    DiveRef($hash, @path);
}

print Dumper $hash;

__DATA__
one
	two
	three
		four
five
	six