aoc2015

commit 9759bd6a2171086377f2c22b3c412810091d7345
parent df80ef0b7cc0d9f69ab10e29c3db6460e1f85c9d
Author: Samir Parikh <noreply@samirparikh.com>
Date:   Fri,  4 Nov 2022 17:39:59 +0000

solve part 1 of day11

Diffstat:
A
day11/Day11.pm
 | 
31
+++++++++++++++++++++++++++++++
A
day11/day11.pl
 | 
25
+++++++++++++++++++++++++

2 files changed, 56 insertions(+), 0 deletions(-)
diff --git a/day11/Day11.pm b/day11/Day11.pm
@@ -0,0 +1,31 @@
+package Day11;
+
+use strict;
+use warnings;
+use v5.32;
+
+use Exporter qw( import );
+our @EXPORT = qw( is_valid_password );
+
+# create expression to match one increasing straight of at least three
+# letters, like abc, bcd, cde, and so on, up to xyz.
+my $number = ord( 'a' );
+my $inc_straight = join "|", map { chr ( $number + $_ ) .
+                                   chr ( $number + $_ + 1 ) .
+                                   chr ( $number + $_ + 2 ) } ( 0 .. 23 );
+
+sub is_valid_password {
+    my $string = shift;
+    say "checking $string...";
+    say "repeating pattern not found" if ( $string !~ m/$inc_straight/ );
+    say "contains invalid character" if ( $string =~ m/[iol]/ );
+    say "no two different, non-overlapping pairs of letters" if ( $string !~ m/(\w)\1.*(\w)\2/ );
+    say "done checking $string.";
+    return 0 if ( $string !~ m/$inc_straight/ ) ||
+                ( $string =~ m/[iol]/ )         ||
+                ( $string !~ m/(\w)\1.*(\w)\2/ );
+    return 1;
+}
+
+
+1;
diff --git a/day11/day11.pl b/day11/day11.pl
@@ -0,0 +1,25 @@
+#!/usr/local/bin/perl
+# day 2015-11
+
+use strict;
+use warnings;
+use v5.32;
+use lib '.';
+use Day11 qw( is_valid_password );
+
+my $password = 'hepxcrrq';
+
+#is_valid_password( $password );
+chomp( my $input = do { local $/; <> } );
+
+foreach ( split /\n/, $input ) {
+    print "$_ is ", is_valid_password($_) ? "" : "not ";
+    say "a valid password.";
+    say "-------------------------";
+}
+
+do { $password++ } until ( is_valid_password( $password ) );
+say "part 1: ", $password;
+
+do { $password++ } until ( is_valid_password( $password ) );
+say "part 2: ", $password;