From: Jan "Yenya" Kasprzak <kas@fi.muni.cz>
Date: Thu, 19 Dec 2024 07:19:25 +0000 (+0100)
Subject: Day 19: regex for part1, cached recursion for part 2
X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?a=commitdiff_plain;h=3c9919e728dfe8649301d19d874b7b5675247678;p=aoc.git

Day 19: regex for part1, cached recursion for part 2
---

diff --git a/2024/37.pl b/2024/37.pl
new file mode 100755
index 0000000..420dbd7
--- /dev/null
+++ b/2024/37.pl
@@ -0,0 +1,10 @@
+#!/usr/bin/perl -w
+
+use v5.40;
+
+chomp($_ = <>);
+my $re = s/, /|/gr;
+my $sum;
+$sum += /^($re)+$/ while <>;
+say $sum;
+
diff --git a/2024/38.pl b/2024/38.pl
new file mode 100755
index 0000000..f79a572
--- /dev/null
+++ b/2024/38.pl
@@ -0,0 +1,26 @@
+#!/usr/bin/perl -w
+
+use v5.40;
+
+my @towels = <> =~ /\w+/g;
+$_ = <>;
+
+my %seen;
+sub walk($rest) {
+	return 1 if !$rest;
+	return $seen{$rest} if exists $seen{$rest};
+	my $count = 0;
+	for my $t (@towels) {
+		next if (my $r1 = $rest) !~ s/^$t//;
+		$count += walk($r1);
+	}
+	return $seen{$rest} = $count;
+}
+
+my $sum;
+while (<>) {
+	chomp;
+	$sum += walk($_);
+}
+say $sum;
+