From 3cb2ce975524b9c6bfd18c3aa2f5061d32493f70 Mon Sep 17 00:00:00 2001
From: Lukas Mai <lukasmai.403@gmail.com>
Date: Mon, 21 Jul 2025 08:52:06 +0200
Subject: add perl solutions for 331

---
 challenge-331/mauke/perl/ch-1.pl |  2 ++
 challenge-331/mauke/perl/ch-2.pl | 28 ++++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)
 create mode 100644 challenge-331/mauke/perl/ch-1.pl
 create mode 100644 challenge-331/mauke/perl/ch-2.pl

diff --git a/challenge-331/mauke/perl/ch-1.pl b/challenge-331/mauke/perl/ch-1.pl
new file mode 100644
index 0000000000..fe86ad9f42
--- /dev/null
+++ b/challenge-331/mauke/perl/ch-1.pl
@@ -0,0 +1,2 @@
+#!/usr/bin/env -S perl -lp
+$_=/\b(\w+)\W*\z/?length$1:0
diff --git a/challenge-331/mauke/perl/ch-2.pl b/challenge-331/mauke/perl/ch-2.pl
new file mode 100644
index 0000000000..afde7757b1
--- /dev/null
+++ b/challenge-331/mauke/perl/ch-2.pl
@@ -0,0 +1,28 @@
+use v5.40;
+
+sub has_duplicate_chars($string) {
+    my %seen;
+    for my $c (split //, $string) {
+        return true
+            if $seen{$c}++;
+    }
+    false
+}
+
+sub are_buddies($source, $target) {
+    my $delta = $source ^. $target;
+    $delta =~ /[^\0]/g
+        or return has_duplicate_chars($source);
+    my $p1 = $-[0];
+    $delta =~ /[^\0]/g
+        or return false;
+    my $p2 = $-[0];
+    return substr($source, $p1, 1) eq substr($target, $p2, 1)
+        && substr($source, $p2, 1) eq substr($target, $p1, 1)
+        && scalar($delta !~ /[^\0]/g);
+}
+
+@ARGV == 2
+    or die "Usage: $0 SOURCE TARGET\n";
+my ($fst, $snd) = @ARGV;
+say are_buddies($fst, $snd) ? 'true' : 'false';
-- 
cgit