The title is the question. How would you write some code to find the longest palindrome from a string? Note that the entire string *may* or *may not* be a palindrome, you must find a substring from said string that is a palindrome. Also note that there are no "special characters" that you should ignore. So a palindrome is just the reverse of the string. So "foo bazzaboof" is not a palindrome because of the space.

Bonus points for speed, readability and general style. More bonus points for writing it in the form of a subroutine so I can benchmark them all. Name the sub after your self.

My attempt is as follows: 
sub buu
{
    my @p;
    my $arg = shift;
    my $p;
    
    while( $arg =~ /((.).?\2)/g )
    {
        my $m = $1;
        while( $arg =~ /((.)$m\2)/ )
        {
            $m = $1;
        }
        if( length($m) > length($p) )
        {
            $p = $m;
        }
    }
    
    return $p;
}

[download]


Update to respond to the criticism: Yes, I did get this problem from the job posting on jobs.perl.org. Yes I had every intention of eventually applying for that job. I had no intention of ripping off people's code to get said job. If I had any intention of using replies to this node for that job, I would have mentioned it. My intentions were simply to share a fun puzzle I found with this community I have grown to love.

Looking at just the facts, in the worst light, I can see how limbic~region, merlyn and others might misinterpret the facts to reach a damning conclusion. I can only say that when I wrote this node, the job had nothing to do with it, so I didn't bother to mention it. That is how my mind works. I can understand why people would have problems with me not mentioning the source, and in retrospect I probably should have credited the source for the problem. Also considering where I got the problem, perhaps I should have waited longer or asked before I "published" the problem. I did not consider the affect this would have on etcshadow and his boss when I wrote this node, and I have already apologized to etcshadow, later on in this thread. I apologize for any impact this may have had on his business.

Having expressed my apologies, I want to reiterate that I have never, nor shall I ever, do something unethical to gain an advantage when applying for a job. I hope my future contributions will make this clear.

Update2, minor formatting changes

Update3, more formatting changes, slightly less inflammatory. Original commented.

In reply to Finding longest palindrome from a string by BUU

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