X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?a=blobdiff_plain;f=2023%2F30.pl;fp=2023%2F30.pl;h=8e813c625615e219c3183356dc2c6795f90c98ea;hb=f141c1ae1581135db4bc9f68aa677c7c499f4956;hp=0000000000000000000000000000000000000000;hpb=ab399e76f3712a096b87cd5a019c6981c3fde323;p=aoc.git

diff --git a/2023/30.pl b/2023/30.pl
new file mode 100755
index 0000000..8e813c6
--- /dev/null
+++ b/2023/30.pl
@@ -0,0 +1,49 @@
+#!/usr/bin/perl -w
+
+use v5.38;
+use experimental 'for_list', 'builtin';
+use builtin 'indexed';
+
+chomp (my $line = <>);
+
+sub hash {
+	$_ = shift;
+	my $n = 0;
+	for (split //) {
+		$n += ord($_);
+		$n *= 17;
+		$n %= 256;
+	}
+	$n;
+}
+
+my @slot;
+
+for (split /,/, $line) {
+	my ($name, $op, $num) = /(\w+)(\W)(\d*)/;
+	my $id = hash($name);
+	my $sl = $slot[$id];
+	if ($op eq '=') {
+		my $found;
+		for my $s (@$sl) {
+			if ($s->[0] eq $name) {
+				$found = 1;
+				$s->[1] = $num;
+			}
+		}
+		if (!$found) {
+			push @$sl, [ $name, $num ];
+		}
+	} elsif ($op eq '-') {
+		@$sl = grep { $_->[0] ne $name } @{ $slot[$id] };
+	}
+}
+
+my $sum;
+for my ($i, $s) (indexed @slot) {
+	for my ($j, $p) (indexed @$s) {
+		$sum += ($i+1) * ($j+1) * $p->[1];
+	}
+}
+say $sum;
+