From: Jan "Yenya" Kasprzak <kas@fi.muni.cz>
Date: Tue, 13 Dec 2022 05:42:40 +0000 (+0100)
Subject: Day 12: not very complicated BFS
X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?p=aoc.git;a=commitdiff_plain;h=6001297e1823f21b5320c1e4a596db630705f9d0

Day 12: not very complicated BFS
---

diff --git a/2022/23.pl b/2022/23.pl
new file mode 100755
index 0000000..960e3ef
--- /dev/null
+++ b/2022/23.pl
@@ -0,0 +1,51 @@
+#!/usr/bin/perl -w
+
+use v5.36;
+use strict;
+use experimental 'multidimensional';
+
+my @m = map { chomp; [ split // ] } <>;
+
+my $xmax = $#{ $m[0] };
+my $ymax = $#m;
+
+my ($sx, $sy);
+for my $y (0 .. $ymax) {
+	for my $x (0 .. $xmax) {
+		if ($m[$y][$x] eq 'S') {
+			$sx = $x; $sy = $y;
+			$m[$y][$x] = 'a';
+		}
+	}
+}
+
+my %seen;
+my @q = [ $sx, $sy ];
+
+while (@q) {
+	my $pt = shift @q;
+	my ($x, $y, @path) = @$pt;
+
+	say "walking ", join(' ', @$pt);
+
+	my $h = $m[$y][$x];
+
+	next if $seen{"$x,$y"}++;
+
+	if ($h eq 'E') {
+		say "FOUND";
+		say scalar @path, ': ', @path;
+		exit 0;
+	}
+
+	for my $pt1 ([-1, 0], [1, 0], [0, -1], [0, 1]) {
+		my ($dx, $dy) = @$pt1;
+		my ($nx, $ny) = ($x+$dx, $y+$dy);
+		next if $nx > $xmax || $nx < 0 || $ny > $ymax || $ny < 0;
+		my $h1 = $m[$ny][$nx];
+		$h1 = 'z' if $h1 eq 'E';
+		say "trying $nx $ny $h $h1";
+		next if ord($h1)-ord($h) > 1;
+		push @q, [ $nx, $ny, @path, " $nx,$ny" ];
+	}
+}
diff --git a/2022/24.pl b/2022/24.pl
new file mode 100755
index 0000000..b63091a
--- /dev/null
+++ b/2022/24.pl
@@ -0,0 +1,57 @@
+#!/usr/bin/perl -w
+
+use v5.36;
+use strict;
+use experimental 'multidimensional';
+
+my @m = map { chomp; [ split // ] } <>;
+
+my $xmax = $#{ $m[0] };
+my $ymax = $#m;
+
+my ($sx, $sy);
+for my $y (0 .. $ymax) {
+	for my $x (0 .. $xmax) {
+		if ($m[$y][$x] eq 'E') {
+			$m[$y][$x] = 'z';
+			$sx = $x; $sy = $y;
+		}
+		if ($m[$y][$x] eq 'S') {
+			$m[$y][$x] = 'a';
+		}
+	}
+}
+
+my %seen;
+my @q = [ $sx, $sy ];
+
+my $minp;
+
+while (@q) {
+	my $pt = shift @q;
+	my ($x, $y, @path) = @$pt;
+
+	say "walking ", join(' ', @$pt);
+
+	my $h = $m[$y][$x];
+
+	next if $seen{"$x,$y"}++;
+
+	if ($h eq 'a') {
+		say "FOUND";
+		say scalar @path, ': ', @path;
+		exit 0;
+	}
+
+	for my $pt1 ([-1, 0], [1, 0], [0, -1], [0, 1]) {
+		my ($dx, $dy) = @$pt1;
+		my ($nx, $ny) = ($x+$dx, $y+$dy);
+		next if $nx > $xmax || $nx < 0 || $ny > $ymax || $ny < 0;
+		my $h1 = $m[$ny][$nx];
+		say "trying $nx $ny $h $h1";
+		next if ord($h1)-ord($h) < -1;
+		push @q, [ $nx, $ny, @path, " $nx,$ny" ];
+	}
+}
+
+say "Min: $minp";