gistfile1.txt

use List::Utils;

class QuickKeyBag {
    has @.values;
    
    method add($value) {
        @.values.push($value);
    }
    
    method roll() {
        @.values.roll;
    }
}

my %next-step;
my $model-text = $*IN.slurp.subst(/"_" | "'"/, "", :global).subst(/<-alpha>+/, " ", :global).lc;
for sliding-window($model-text.comb(/<alpha> | \s/), 3) -> $a, $b, $c {
    my $last-two = $a ~ $b;
    %next-step{$last-two} = QuickKeyBag.new if %next-step{$last-two} !~~ QuickKeyBag;
    %next-step{$last-two}.add($c);
}

my @chain := 'a', ' ', -> $a, $b { %next-step{$a ~ $b}.roll } ... *;
say @chain[^80];

# for %next-step.keys.sort -> $letter {
#     say "$letter: { %next-step{$letter}.values.join }";
# }