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diff --git a/challenge-339/robbie-hatley/blog.txt b/challenge-339/robbie-hatley/blog.txt
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+https://hatley-software.blogspot.com/2025/09/robbie-hatleys-solutions-in-perl-for_16.html
diff --git a/challenge-339/robbie-hatley/perl/ch-1.pl b/challenge-339/robbie-hatley/perl/ch-1.pl
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+#!/usr/bin/env perl
+
+=pod
+
+--------------------------------------------------------------------------------------------------------------
+TITLE AND ATTRIBUTION:
+Solutions in Perl for The Weekly Challenge 339-1,
+written by Robbie Hatley on Mon Sep 15, 2025.
+
+--------------------------------------------------------------------------------------------------------------
+PROBLEM DESCRIPTION:
+Task 339-1: Max Diff
+Submitted by: Mohammad Sajid Anwar
+You are given an array of integers having four or more elements.
+Write a script to find two pairs of numbers from this list (WITH
+4 DISTINCT INDEXES WITHIN THE ARRAY) so that the difference
+between their products is maximum. Return the max difference.
+
+With Two pairs (a, b) and (c, d), the product difference is
+(a * b) - (c * d).
+
+Example 1
+Input:  (5, 9, 3, 4, 6)
+Output: 42
+Pair 1: (9, 6)
+Pair 2: (3, 4)
+Product Diff: (9 * 6) - (3 * 4) => 54 - 12 => 42
+
+Example 2
+Input:  (1, -2, 3, -4)
+Output: 10
+Pair 1: (1, -2)
+Pair 2: (3, -4)
+
+Example 3
+Input:  (-3, -1, -2, -4)
+Output: 10
+Pair 1: (-1, -2)
+Pair 2: (-3, -4)
+
+Example 4
+Input:  (10, 2, 0, 5, 1)
+Output: 50
+Pair 1: (10, 5)
+Pair 2: (0, 1)
+
+Example 5
+Input: @ints = (7, 8, 9, 10, 10)
+Output: 44
+Pair 1: (10, 10)
+Pair 2: (7, 8)
+
+--------------------------------------------------------------------------------------------------------------
+PROBLEM NOTES:
+To solve this problem, I generate all possible "pairs of pairs" of numbers from the array such that all four
+numbers have unique indexes. I compute the difference of the products of the pairs, and keep track of the
+maximum difference seen, then return the maximum.
+
+--------------------------------------------------------------------------------------------------------------
+IO NOTES:
+Input is via either built-in variables or via @ARGV. If using @ARGV, provide one argument which must be a
+single-quoted array of arrays of 4-or-more numbers, in proper Perl syntax, like so:
+
+./ch-1.pl '([3,82,-47,56,8],[3.13,7.41,3.62,7.85])'
+
+Output is to STDOUT and will be each input followed by the corresponding output.
+
+=cut
+
+# ------------------------------------------------------------------------------------------------------------
+# PRAGMAS, MODULES, AND SUBS:
+
+   use v5.36;
+   use utf8::all;
+   use POSIX 'Inf';
+
+   # What is the maximum difference of products
+   # of any two pairs of numbers from an array?
+   sub max_diff ($aref) {
+      my $n = scalar(@$aref);
+      my $max = -Inf;
+      for          my $i (0..$n-1) {
+         for       my $j (0..$n-1) {
+            for    my $k (0..$n-1) {
+               for my $l (0..$n-1) {
+                  next if $i==$j || $i==$k || $i==$l
+                       || $j==$k || $j==$l || $k==$l;
+                  my $a = $$aref[$i]; my $b = $$aref[$j];
+                  my $c = $$aref[$k]; my $d = $$aref[$l];
+                  my $diff = $a*$b - $c*$d;
+                  if ($diff > $max) {$max = $diff}}}}}
+      $max}
+
+# ------------------------------------------------------------------------------------------------------------
+# INPUTS:
+my @arrays = @ARGV ? eval($ARGV[0]) :
+(
+   [5, 9, 3, 4, 6]   , # Expected output: 42
+   [1, -2, 3, -4]    , # Expected output: 10
+   [-3, -1, -2, -4]  , # Expected output: 10
+   [10, 2, 0, 5, 1]  , # Expected output: 50
+   [7, 8, 9, 10, 10] , # Expected output: 44
+);
+
+# ------------------------------------------------------------------------------------------------------------
+# MAIN BODY OF PROGRAM:
+$"=', ';
+for my $aref (@arrays) {
+   say '';
+   say "Array = (@$aref)";
+   my $md = max_diff($aref);
+   say "Maximum different of pair products = $md";
+}
diff --git a/challenge-339/robbie-hatley/perl/ch-2.pl b/challenge-339/robbie-hatley/perl/ch-2.pl
new file mode 100755
index 0000000000..3eb92e680a
--- /dev/null
+++ b/challenge-339/robbie-hatley/perl/ch-2.pl
@@ -0,0 +1,91 @@
+#!/usr/bin/env perl
+
+=pod
+
+--------------------------------------------------------------------------------------------------------------
+TITLE AND ATTRIBUTION:
+Solutions in Perl for The Weekly Challenge 339-2,
+written by Robbie Hatley on Mon Sep 15, 2025.
+
+--------------------------------------------------------------------------------------------------------------
+PROBLEM DESCRIPTION:
+Task 339-2: Peak Point
+Submitted by: Mohammad Sajid Anwar
+You are given an array of altitude changes. Write a script to
+find the maximum altitude attained, assuming that one starts
+at altitude 0.
+
+Example 1
+Input:  [-5, 1, 5, -9, 2]
+Output: 1
+
+
+Example 2
+Input:  [10, 10, 10, -25]
+Output: 30
+
+Example 3
+Input:  [3, -4, 2, 5, -6, 1]
+Output: 6
+
+Example 4
+Input:  [-1, -2, -3, -4]
+Output: 0
+
+Example 5
+Input:  [-10, 15, 5]
+Output: 10
+
+--------------------------------------------------------------------------------------------------------------
+PROBLEM NOTES:
+To solve this problem, I keep track of "current" and and "max" altitudes reached after each altitude change,
+then return max.
+
+--------------------------------------------------------------------------------------------------------------
+IO NOTES:
+Input is via either built-in variables or via @ARGV. If using @ARGV, provide one argument which must be a
+single-quoted array of arrays of numbers, in proper Perl syntax, like so:
+
+./ch-2.pl '([-35.2, 38.7, -14.9, 13.9],[1,2,3,4,-1,-2,-3,-4])'
+
+Output is to STDOUT and will be each input followed by the corresponding output.
+
+=cut
+
+# ------------------------------------------------------------------------------------------------------------
+# PRAGMAS, MODULES, AND SUBS:
+
+   use v5.36;
+   use utf8::all;
+
+   # What is the maximum
+   # altitude attained?
+   sub max_alt ($aref) {
+      my $cur = 0;
+      my $max = 0;
+      for my $change (@$aref) {
+         $cur += $change;
+         if ($cur > $max) {
+            $max = $cur}}
+      $max}
+
+# ------------------------------------------------------------------------------------------------------------
+# INPUTS:
+my @arrays = @ARGV ? eval($ARGV[0]) :
+(
+   [-5, 1, 5, -9, 2]    , # Expected output: 1
+   [10, 10, 10, -25]    , # Expected output: 30
+   [3, -4, 2, 5, -6, 1] , # Expected output: 6
+   [-1, -2, -3, -4]     , # Expected output: 0
+   [-10, 15, 5]         , # Expected output: 10
+);
+
+# ------------------------------------------------------------------------------------------------------------
+# MAIN BODY OF PROGRAM:
+$"=', ';
+for my $aref (@arrays) {
+   say '';
+   say "Altitude changes = (@$aref)";
+   my $tac = max_alt($aref);
+   say "Maximum altitude = $tac";
+}