#! perl -slw
use strict;
use Data::Dump qw[ pp ];

my $string = "BEHACJBDLCENADFEGOFHQAGIHJRBIKJLSCKMLNTDMOFNPOQTGPRIQSKR
+TMPS";
my @results = map [ split''], unpack '(a3)*', $string;

unshift @results, undef; ## Make the data start at index 1

pp \@results;
__END__
c:\test>junk4
[
  undef,
  ["B", "E", "H"],
  ["A", "C", "J"],
  ["B", "D", "L"],
  ["C", "E", "N"],
  ["A", "D", "F"],
  ["E", "G", "O"],
  ["F", "H", "Q"],
  ["A", "G", "I"],
  ["H", "J", "R"],
  ["B", "I", "K"],
  ["J", "L", "S"],
  ["C", "K", "M"],
  ["L", "N", "T"],
  ["D", "M", "O"],
  ["F", "N", "P"],
  ["O", "Q", "T"],
  ["G", "P", "R"],
  ["I", "Q", "S"],
  ["K", "R", "T"],
  ["M", "P", "S"],
]
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