sub fizbin {
return $_[0] unless ($_[0] and length($_[0]) > 1);
my @string = (300, unpack("U*", $_[0]), 301);
my $palstart, $palend;
my ($bestlen, $beststart, $bestend) = (-1,-1,-1);
for ($palmid = 1; $palmid < $#string; $palmid++)
{
if ($string[$palmid] == $string[$palmid+1])
{ # try even-length palindrome
($palstart, $palend) = ($palmid, $palmid+1);
while ($string[$palend+1] == $string[$palstart-1])
{
$palend++; $palstart--;
}
if ($bestlen < $palend - $palstart)
{
($bestlen, $bestend, $beststart) =
($palend - $palstart, $palend, $palstart);
}
}
# try odd-length palindrome
($palstart, $palend) = ($palmid, $palmid);
while ($string[$palend+1] == $string[$palstart-1])
{
$palend++; $palstart--;
}
if ($bestlen < $palend - $palstart)
{
($bestlen, $bestend, $beststart) =
($palend - $palstart, $palend, $palstart);
}
}
pack("U*", @string[$beststart..$bestend]);
}
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