- Added solutions by PokGoPun.

- Added solutions by Feng Chang.
- Added solutions by Niels van Dijke.
- Added solutions by Simon Proctor.
- Added solutions by Mohammad Anwar.

3 files changed, 42 insertions, 0 deletions

diff --git a/challenge-339/mohammad-anwar/perl/ch-1.pl b/challenge-339/mohammad-anwar/perl/ch-1.pl
new file mode 100644
index 0000000000..265579d0a8
--- /dev/null
+++ b/challenge-339/mohammad-anwar/perl/ch-1.pl
@@ -0,0 +1,42 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+use Test::More;
+use List::Util qw/max/;
+
+sub max_diff {
+    my @nums = @_;
+
+    # For 4 elements, there are only 3 possible pairings
+    if (@nums == 4) {
+        my ($a, $b, $c, $d) = @nums;
+        return max(
+            $a*$b - $c*$d,
+            $a*$c - $b*$d,
+            $a*$d - $b*$c,
+        );
+    }
+
+    # For larger arrays, we need to consider extreme values
+    my @s = sort {$a <=> $b} @nums;
+
+    # The maximum difference will likely come from:
+    # Option 1: (two largest) vs (two smallest)
+    # Option 2: (largest*smallest) vs (second largest*second smallest)
+    # Option 3: (largest*second smallest) vs (second largest*smallest)
+
+    my $opt1 = $s[-1]*$s[-2] -  $s[0]*$s[1];
+    my $opt2 = $s[-1]*$s[0]  - $s[-2]*$s[1];
+    my $opt3 = $s[-1]*$s[1]  - $s[-2]*$s[0];
+
+    return max($opt1, $opt2, $opt3);
+}
+
+is(max_diff(5,9,3,4,6),   42);
+is(max_diff(1,-2,3,-4),   10);
+is(max_diff(-3,-1,-2,-4), 10);
+is(max_diff(10,2,0,5,1),  50);
+is(max_diff(7,8,9,10,10), 44);
+
+done_testing;
diff --git a/challenge-339/perlboy1967/perl/ch1.pl b/challenge-339/perlboy1967/perl/ch-1.pl
index ed0a6212b0..ed0a6212b0 100755
--- a/challenge-339/perlboy1967/perl/ch1.pl
+++ b/challenge-339/perlboy1967/perl/ch-1.pl
diff --git a/challenge-339/perlboy1967/perl/ch2.pl b/challenge-339/perlboy1967/perl/ch-2.pl
index 63c29a8dc8..63c29a8dc8 100755
--- a/challenge-339/perlboy1967/perl/ch2.pl
+++ b/challenge-339/perlboy1967/perl/ch-2.pl