ch-1.pl

#!/usr/bin/perl
use 5.030;
use warnings;

my %spelling = (
    1 => 'one',
    2 => 'two',
    3 => 'three',
    4 => 'four',
    5 => 'five',
    6 => 'six',
    7 => 'seven',
    8 => 'eight',
    9 => 'nine',
    10 => 'ten',
    11 => 'eleven',
    12 => 'twelve',
    13 => 'thirteen',
    14 => 'fourteen',
    15 => 'fifteen',
    16 => 'sixteen',
    17 => 'seventeen',
    18 => 'eighteen',
    19 => 'nineteen',
    100 => 'hundred'
);

my @tens = (
    undef,
    undef,
    'twenty',
    'thirty',
    'forty',
    'fifty',
    'sixty',
    'seventy',
    'eighty',
    'ninety',
);

for my $n (20 .. 99) {
    my ($ten, $unit) = split //, $n;
    $spelling{$n} = $tens[$ten] . ($unit == 0 ? q{} : "-$spelling{$unit}");
}

say join q{, }, sort { $a <=> $b } grep { $spelling{$_} !~ /e/; } keys %spelling;