Please read Writeup Formatting Tips and update your post with proper markup. Thank you.

What you can do something along these lines: 

my $previous = <IN>;
while (<IN>) {
   # compare $_ and $previous here


   $previous = $_;
}

[download]

In reply to Re: compare subsequent lines by moritz
in thread compare subsequent lines by kevester

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


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