adventofcode/2018/09/sol1.pl

45 lines
885 B
Perl

use 5.20.0;
use warnings;
use experimental qw/
signatures
postderef
/;
my @marbles;
my $next_marble = 0;
my $index = 0;
my $nbr_elves = 419;
my $current_elf = 0;
my $last_marble = 72164 * 100;
my %score;
while() {
warn $next_marble if 0 == $next_marble % 10_000;
last if $next_marble > $last_marble;
if( $next_marble > 0 and 0 == $next_marble % 23 ) {
$index = ( $index - 7 + @marbles ) % @marbles;
my $score = $next_marble + splice @marbles, $index, 1;
$score{$current_elf} += $score;
}
else {
$index = ( $index + 2 ) % ( @marbles || 1 );
splice @marbles, $index, 0, $next_marble;
}
# say join ' ', @marbles;
# my $x = <>;
$next_marble++;
$current_elf++;
$current_elf %= $nbr_elves;
}
use List::UtilsBy qw/ max_by /;
use List::AllUtils qw/ pairs max /;
say max values %score;