in reply to How to implement Linked List

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;

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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];
}

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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.

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Re^2: How to implement Linked List
by msk_0984 (Friar) on Dec 19, 2006 at 05:50 UTC
    Hi Monks,


            Firstly i would like to thank you for ur replies and it was really a good thing to get the ideas and views of well experienced people.

            Most said Perl has built in fully dynamic data structures - arrays and hashes. These are in most cases sufficient for resident data needs. We have the extended featured functions for th ease in order to exploit the programming abilities....


    FUNCTIONS: pop , push , splice , shift , unshift and many more and dont want to use etc.....

    As jonadab said ...........

    It's kinda like asking, "How do I implement an insertion sort in Perl?" or, to use a non-Perl example, "How do I tack in a speedboat?" Everyone's going to look at you funny and ask, "Why?"

    But any wayz i felt it some thing like of learning a lot from all of you.

    Work Hard Party Harderrr!!
    Sushil Kumar
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