From: Jan "Yenya" Kasprzak <kas@fi.muni.cz>
Date: Sun, 22 Dec 2024 05:29:27 +0000 (+0100)
Subject: Day 22: walls of incomprehensible text
X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?a=commitdiff_plain;h=d95cb8df14f1bb2a7b262d3ac26651622bb51412;p=aoc.git

Day 22: walls of incomprehensible text
---

diff --git a/2024/43.pl b/2024/43.pl
new file mode 100755
index 0000000..477ea8c
--- /dev/null
+++ b/2024/43.pl
@@ -0,0 +1,19 @@
+#!/usr/bin/perl -w
+
+use v5.40;
+
+my $sum;
+while (<>) {
+	chomp;
+	my $n=$_;
+	for (1 .. 2000) {
+		$n ^= $n << 6;
+		$n &= (1 << 24) - 1;
+		$n ^= $n >> 5;
+		$n &= (1 << 24) - 1;
+		$n ^= $n << 11;
+		$n &= (1 << 24) - 1;
+	}
+	$sum += $n;
+}
+say $sum;
diff --git a/2024/44.pl b/2024/44.pl
new file mode 100755
index 0000000..3d7faa3
--- /dev/null
+++ b/2024/44.pl
@@ -0,0 +1,37 @@
+#!/usr/bin/perl -w
+
+use v5.40;
+use List::Util qw(max);
+
+my %segs;
+while (<>) {
+	chomp;
+	my $n=$_;
+	my $prev = $n;
+	my %seen;
+	my @seq;
+	for (1 .. 2000) {
+		$n ^= $n << 6;
+		$n &= (1 << 24) - 1;
+		$n ^= $n >> 5;
+		$n &= (1 << 24) - 1;
+		$n ^= $n << 11;
+		$n &= (1 << 24) - 1;
+		my $p = $n % 10;
+		if (defined $prev) {
+			push @seq, $p - $prev;
+			shift @seq if @seq > 4;
+			if (@seq == 4) {
+				my $k = join(',', @seq);
+				$seen{$k} //= $p;
+			}
+		}
+		$prev = $p;
+	}
+	for my $k (keys %seen) {
+		$segs{$k} += $seen{$k};
+	}
+}
+say max values %segs;
+
+# BEGIN { t; }