CueUp/greplin Level 1 - Longest Palindrome Substring

gistfile1.txt

use strict;
use warnings;

open my $inputFH, '<', 'block.txt';
while (my $line = <$inputFH>) {
  chomp $line;
  my @letters = split(//, $line);

  # For every letter in the string
  for (my $letter = 0; $letter < scalar @letters; $letter++) {
    print $letters[$letter], "\n";

    # Case for an odd, and thus possibly continuing palindrome
    my $distance = 0;
    while (uc($letters[$letter - $distance]) eq uc($letters[$letter + $distance])) {
      $distance++;
      print $distance, substr($line, $letter - $distance, $distance * 2), "\n";
    }
  }
}