Beefy Boxes and Bandwidth Generously Provided by pair Networks
Clear questions and runnable code
get the best and fastest answer
 
PerlMonks  

comment on

( [id://3333]=superdoc: print w/replies, xml ) Need Help??

I'm trying to create a pair of hashes so that I can easily traverse a list of filenames in either direction. The code I've come up with follows. Does anybody know a more efficient way to do this? Preferably so that I can remove the ugly "do first case, loop by index, do last case" thing I've got. I'd prefer one loop but didn't want to put a pair of ifs inside that will only be used once each.

# populate filename array my @filenames = qw(file1 file2 file3 file4 file5 file6); my %next; my %prev; # Link next to first filename $next{$filenames[0]} = $filenames[1]; # Link next and prev to all the filenames for (my $fileindex = 1; $fileindex < scalar (@filenames) - 1; $fileind +ex++) { $next{$filenames[$fileindex]} = $filenames[$fileindex + 1]; $prev{$filenames[$fileindex]} = $filenames[$fileindex - 1]; } # Link prev to last filename $prev{$filenames[-1]} = $filenames[-2];

Thanks, monks.

--
Grant me the wisdom to shut my mouth when I don't know what I'm talking about.


In reply to Efficient Linked Lists by Ionizor

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



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others having an uproarious good time at the Monastery: (12)
As of 2024-04-23 14:55 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found