Dose anyone know how to count nodes numbers in a linked list or could anyone tell me which book should I start with to learn about linked list? Thanks a lot ! The question is from codility.com, which I use it to evaluate my coding ability recently. Due to the copyright problem, I need to remove it from here, My bad ! please check the original qestion below:

https://codility.com/honeypot/Perl_is_Perls-Perl-test-1 Here comes the codes I come up with, thanks for all your explanation of linked list data structure :

sub solution

{

my ($L)=@_;

my $count=1;

while($L=$L->{'next'})

{

$count++;

last if $L->{'value'} eq 'undef';

}

return $count;

}

In reply to Perl linked list by Perl_is_Perl

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