From: Jan "Yenya" Kasprzak <kas@fi.muni.cz>
Date: Mon, 23 Dec 2024 05:48:29 +0000 (+0100)
Subject: Day 23: strongly connected graph components
X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?a=commitdiff_plain;h=e662a2b0d9a7a037b9911d83477039be4583fda2;p=aoc.git

Day 23: strongly connected graph components
---

diff --git a/2024/45.pl b/2024/45.pl
new file mode 100755
index 0000000..97a4351
--- /dev/null
+++ b/2024/45.pl
@@ -0,0 +1,22 @@
+#!/usr/bin/perl -w
+
+use v5.40;
+
+my %conn;
+while (<>) {
+	my ($x, $y) = /\w+/g;
+	$conn{$x}{$y}++;
+	$conn{$y}{$x}++;
+}
+
+my $count;
+for my $x (keys %conn) {
+	for my $y (keys $conn{$x}->%*) {
+		for my $z (keys $conn{$x}->%*) {
+			next if $z eq $y;
+			next if !$conn{$z}{$y};
+			$count++ if $x =~ /^t/ || $y =~ /^t/ || $z =~ /^t/;
+		}
+	}
+}
+say $count / 6;
diff --git a/2024/46.pl b/2024/46.pl
new file mode 100755
index 0000000..7310847
--- /dev/null
+++ b/2024/46.pl
@@ -0,0 +1,27 @@
+#!/usr/bin/perl -w
+
+use v5.40;
+
+my %conn;
+while (<>) {
+	my ($x, $y) = /\w+/g;
+	$conn{$x}{$y}++;
+	$conn{$y}{$x}++;
+}
+
+sub walk {
+	my ($set, @todo) = @_;
+	my @max = @$set;
+	X:
+	while (my $x = shift @todo) {
+		for my $y (@$set) {
+			next X if !$conn{$x}{$y};
+		}
+		my @nset = walk([ @$set, $x ], @todo);
+		@max = @nset
+			if @nset > @max;
+	}
+	return @max;
+}
+say join(',', walk([], sort keys %conn));
+