adventofcode/2017/12/1.pl

32 lines
618 B
Perl
Raw Permalink Normal View History

2017-12-28 17:15:15 +00:00
use 5.20.0;
use List::AllUtils qw/ pairmap /;
use experimental 'postderef';
my %pipe = pairmap { $a => [ split ', ', $b] } map { split ' <-> ' }
map { chomp; $_ }<>;
use DDP;
for my $from (keys %pipe ) {
my @i = $pipe{$from}->@*;
for my $i ( @i ) {
push $pipe{$i}->@*, $from;
}
}
my @group = ( 0 );
my @unprocessed = $pipe{0}->@*;
my %seen = ( 0 => 1 );
while( @unprocessed ) {
my $next = shift @unprocessed;
warn $next;
next if $seen{$next}++;
warn join " ", $pipe{$next}->@*;
push @unprocessed, $pipe{$next}->@*;
}
say join " ", keys %seen;
say scalar keys %seen;