in reply to looping backwards

I'd use a slice: 
#!/usr/bin/perl

use strict;
use warnings;

my @arr = qw /Fred Mark Joe Mary Paul/;

local $, = " ";
for (my $o = 0; $o < @arr; $o ++) {
    print "$o:", @arr [$#arr - $o + 1 .. $#arr, 0 .. $#arr - $o], "\n"
+;
}
__END__

0: Fred Mark Joe Mary Paul 
1: Paul Fred Mark Joe Mary 
2: Mary Paul Fred Mark Joe 
3: Joe Mary Paul Fred Mark 
4: Mark Joe Mary Paul Fred

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Abigail

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Re: Re: looping backwards
by eyepopslikeamosquito (Archbishop) on Jul 30, 2003 at 03:19 UTC

    Very nice. Minor shortening to:

    @arr [@arr - $o .. $#arr, 0 .. $#arr - $o]

    [download]

    Using the % trick, you might try this instead:

    @arr [map $_ % @arr, @arr - $o .. @arr - $o + $#arr]

or:

my $p = @arr - $o; @arr [map $p++ % @arr, @arr]

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    So your slice looks a bit better.

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