Year 2016, days 1-10: so far pretty interesting

[aoc.git] / 2016 / 01.pl

diff --git a/2016/01.pl b/2016/01.pl
new file mode 100755 (executable)
index 0000000..42982f0
--- /dev/null
+++ b/2016/01.pl
@@ -0,0 +1,23 @@
+#!/usr/bin/perl -w
+
+use strict;
+use v5.30;
+
+my @dir = ([0, -1], [1, 0], [0, 1], [-1, 0]);
+my $d = 0;
+
+my ($x, $y) = (0, 0);
+
+$_ = <>;
+while (/([LR])(\d+)/g) {
+       if ($1 eq 'L') {
+               $d = $#dir if --$d < 0;
+       } else {
+               $d = 0 if ++$d > $#dir;
+       }
+       $x += $2 * $dir[$d]->[0];
+       $y += $2 * $dir[$d]->[1];
+}
+
+say abs($x)+abs($y);
+