From: Jan "Yenya" Kasprzak <kas@fi.muni.cz>
Date: Sun, 7 Dec 2025 05:18:05 +0000 (+0100)
Subject: Day 07: beams
X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?a=commitdiff_plain;h=656976ee2da9d29fbb1cd7c2c3d015369acf2459;p=aoc.git

Day 07: beams
---

diff --git a/2025/13.pl b/2025/13.pl
new file mode 100755
index 0000000..615836c
--- /dev/null
+++ b/2025/13.pl
@@ -0,0 +1,23 @@
+#!/usr/bin/perl -w
+
+use v5.42;
+
+my %beams;
+($_ = <>) =~ /S/g;
+$beams{pos()-1}++;
+
+my $splits;
+while (<>) {
+	my %newb;
+	for my $b (keys %beams) {
+		if (substr($_, $b, 1) eq '^') {
+			$newb{$b-1}++ if $b > 0;
+			$newb{$b+1}++ if $b < length;
+			$splits++;
+		} else {
+			$newb{$b}++;
+		}
+	}
+	%beams = %newb;
+}
+say $splits;
diff --git a/2025/14.pl b/2025/14.pl
new file mode 100755
index 0000000..7648cb4
--- /dev/null
+++ b/2025/14.pl
@@ -0,0 +1,22 @@
+#!/usr/bin/perl -w
+
+use v5.42;
+use List::Util qw(sum);
+
+my %beams;
+($_ = <>) =~ /S/g;
+$beams{pos()-1}++;
+
+while (<>) {
+	my %newb;
+	for my $b (keys %beams) {
+		if (substr($_, $b, 1) eq '^') {
+			$newb{$b-1} += $beams{$b} if $b > 0;
+			$newb{$b+1} += $beams{$b} if $b < length;
+		} else {
+			$newb{$b} += $beams{$b};
+		}
+	}
+	%beams = %newb;
+}
+say sum values %beams;