- Added solutions by Robbie Hatley.

- Added solutions by Luca Ferrari.
- Added solutions by PokGoPun.
- Added solutions by Roger Bell_West.
- Added solutions by Jan Krnavek.
- Added solutions by Jorg Sommrey.
- Added solutions by Adam Russell.
- Added solutions by Reinier Maliepaard.

4 files changed, 130 insertions, 0 deletions

diff --git a/challenge-272/reinier-maliepaard/blog.txt b/challenge-272/reinier-maliepaard/blog.txt
new file mode 100644
index 0000000000..7d54963077
--- /dev/null
+++ b/challenge-272/reinier-maliepaard/blog.txt
@@ -0,0 +1 @@
+https://reiniermaliepaard.nl/perl/pwc/index.php?id=pwc272
diff --git a/challenge-272/reinier-maliepaard/perl/ch-1.pl b/challenge-272/reinier-maliepaard/perl/ch-1.pl
new file mode 100644
index 0000000000..1c6542cc84
--- /dev/null
+++ b/challenge-272/reinier-maliepaard/perl/ch-1.pl
@@ -0,0 +1,53 @@
+#!/usr/bin/perl
+use strict;
+use warnings;
+
+=begin
+  Here my solution TASK #1 along with alternatives from Niels van Dijke and James Curtis-Smith.
+  I did some benchmark (https://metacpan.org/pod/Benchmark) with 'timethese':
+  James' join+split is the fastest solution, even when the validation in Niels' and my
+  solution is removed
+=cut
+
+use Data::Validate::IP qw(is_ipv4);
+
+sub defangIP {
+
+    if (is_ipv4($_[0])) {
+        $_[0] =~ s/\./[.]/g;
+    }
+    else {
+        print("No valid IP address!");
+    }
+
+# Inspired by Niels van Dijke's oneliner which uses the necessary /r switch
+# (Niels uses for validation another module Net::IP)
+#    (is_ipv4($_[0])) ? $_[0] =~ s/\./[.]/gr : "No valid IP address!";
+
+# James Curtis-Smith solution:
+#    join '[.]', split /\./, $_[0];
+}
+
+# TESTS
+my $ip;
+
+# Example 1
+$ip = "1.1.1.1";
+print(defangIP($ip), "\n"); # Output: 1[.]1[.]1[.]1
+
+# Example 2
+$ip = "255.101.1.0";
+print(defangIP($ip), "\n"); # Output: 255[.]101[.]1[.]0
+
+# Example 3
+$ip = "123.234.345.001";
+print(defangIP($ip), "\n"); # Output: "No valid IP address!
+
+# Example 4
+# From: https://metacpan.org/pod/Data::Validate::IP
+# There are security implications to this around certain oddly formed addresses.
+# Notably, an address like "010.0.0.1" is technically valid, but the operating
+# system will treat '010' as an octal number: '010.0.0.1' is interpreted as '8.0.0.1'
+# James' solution and Niels' original do not take that into account.
+$ip = "010.0.0.1";
+print(defangIP($ip), "\n"); # Output: "No valid IP address!
diff --git a/challenge-272/reinier-maliepaard/perl/ch-2.pl b/challenge-272/reinier-maliepaard/perl/ch-2.pl
new file mode 100644
index 0000000000..e67813f50c
--- /dev/null
+++ b/challenge-272/reinier-maliepaard/perl/ch-2.pl
@@ -0,0 +1,60 @@
+#!/usr/bin/perl
+use strict;
+use warnings;
+use Benchmark qw(:all);
+
+=begin
+  Here is my solution for TASK #2, along with alternatives from
+  Niels van Dijke and James Curtis-Smith. I shared the benchmark results,
+  which show some variability when run multiple times. Nonetheless, James's
+  solution is the fastest.
+=cut
+
+# Reinier Maliepaard: function to calculate total sum using split and for
+sub ascii_differences_sum_split_1 {
+    my @chars = split(//, $_[0]);
+    my $total_sum = 0;
+
+    for my $i (0 .. $#chars - 1) {
+        $total_sum += abs(ord($chars[$i]) - ord($chars[$i + 1]));
+    }
+
+    return($total_sum);
+}
+
+# James Curtis-Smith: function to calculate total sum using split and for
+sub ascii_differences_sum_split_2 {
+    my ($t, @l) = (0, split //, $_[0]);
+
+    my $f = ord shift @l;
+
+    ($t += abs($f - ord)), $f=ord for @l;
+
+    $t;
+}
+
+# Niels van Dijke: function to calculate total sum using sum0 and slide
+use List::Util qw(sum0);
+use List::MoreUtils qw(slide);
+
+sub ascii_differences_sum_slide {
+  sum0 slide {abs(ord($b) - ord($a))} split '',$_[0]
+}
+
+# A fanciful creation by fans, combining various Elvish elements from Tolkien's work.
+my $input_string = "Aearenuialinorosinaiantirnoitisirsiensinoit";
+
+# Benchmark all three methods
+timethese(1000000, {
+    'Using split_1' => sub { ascii_differences_sum_split_1($input_string) },
+    'Using split_2' => sub { ascii_differences_sum_split_2($input_string) },
+    'Using slide'   => sub { ascii_differences_sum_slide($input_string) },
+});
+
+=begin
+Results:
+  Benchmark: timing 1000000 iterations of Using slide, Using split_1, Using split_2...
+  Using slide:   7 wallclock secs ( 6.55 usr +  0.00 sys =  6.55 CPU) @ 152671.76/s (n=1000000)
+  Using split_1: 7 wallclock secs ( 6.87 usr +  0.00 sys =  6.87 CPU) @ 145560.41/s (n=1000000)
+  Using split_2: 6 wallclock secs ( 5.76 usr +  0.00 sys =  5.76 CPU) @ 173611.11/s (n=1000000)
+=cut
diff --git a/challenge-272/reinier-maliepaard/perl/ch-2a.pl b/challenge-272/reinier-maliepaard/perl/ch-2a.pl
new file mode 100644
index 0000000000..5c2b34ddce
--- /dev/null
+++ b/challenge-272/reinier-maliepaard/perl/ch-2a.pl
@@ -0,0 +1,16 @@
+#!/usr/bin/perl
+use strict;
+use warnings;
+
+sub ascii_differences_sum_split_2_alt
+{
+    my ( $t, @list ) = ( 0, split(//, $_[0]) );
+
+    my $f = ord( shift(@list) );
+
+    for (@list) {
+        $t += abs( $f - ord($_) );
+        $f = ord($_);
+    }
+    return($t);
+}