A simple linked list would be [ 'a' [ 'b' [ 'c', undef]]]. This is more clear if you look at it like this: 
$c = ['c', undef];
$b = ['b', undef];
$a = ['a', undef];

$a->[1] = $b;
$b->[1] = $c;

[download]
This is the same as the hash version above, but using arrays. You would travers this list like this: 
my $current = $a;

while (defined $current) {
    my $value = $current->[0];
    ...
    $current = $current->{1];
}

[download]
This is no different than the hash version above, but should be a bit more efficient.

The main point is that a linked list is made up of elements that contain data and a pointer to the next element. In the case of a double linked list 2 pointers -- one to the previous element and one to the next element.

-- gam3
A picture is worth a thousand words, but takes 200K.

In reply to Re: How to implement Linked List by gam3
in thread How to implement Linked List by msk_0984

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