#!/usr/bin/perl

# https://perlmonks.org/?node_id=1227147

use warnings;
use strict;

my $short_pattern = 'FTTF';

my @result = grep { 
                $short_pattern = ( chop $short_pattern ) . $short_patt
+ern;
                $short_pattern ge 'T' 
                } 0 .. 12;

print "@result\n";
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