here is my code: 
sub palindrome{
my $x=shift;
my $prev=0;
while ($x=~/(([a-z0-9]+)[a-z0-9]?(??{reverse $2}))/gi)
{
    $max=$1 if (length($1)>$prev);
    $prev=length $max;
}
$max
}

[download]

update:

Sorry monks i haven't read the question carefully, left out space condition itself.

In reply to Re: Finding longest palindrome from a string by murugu
in thread Finding longest palindrome from a string by BUU

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