From 6afc92bb1d9f1a4444bda22f20bbb173ab2a02aa Mon Sep 17 00:00:00 2001
From: Randy Lauen <randy.lauen@gmail.com>
Date: Tue, 27 Aug 2019 23:01:08 -0500
Subject: some solutions

---
 challenge-023/randy-lauen/perl5/ch-1.pl | 30 +++++++++++++++++++
 challenge-023/randy-lauen/perl6/ch-1.p6 | 27 +++++++++++++++++
 challenge-023/randy-lauen/perl6/ch-2.p6 | 53 +++++++++++++++++++++++++++++++++
 3 files changed, 110 insertions(+)
 create mode 100644 challenge-023/randy-lauen/perl5/ch-1.pl
 create mode 100644 challenge-023/randy-lauen/perl6/ch-1.p6
 create mode 100644 challenge-023/randy-lauen/perl6/ch-2.p6

diff --git a/challenge-023/randy-lauen/perl5/ch-1.pl b/challenge-023/randy-lauen/perl5/ch-1.pl
new file mode 100644
index 0000000000..2b8533c330
--- /dev/null
+++ b/challenge-023/randy-lauen/perl5/ch-1.pl
@@ -0,0 +1,30 @@
+#!/usr/bin/env perl
+
+=head1 SYNOPSIS
+
+Task:
+Create a script that prints nth order forward difference series. You should be a 
+able to pass the list of numbers and order number as command line parameters.
+
+Usage:
+    $ perl ch-1.pl --order=1 5 9 2 8 1 6
+
+=cut
+
+use strict;
+use warnings;
+use feature 'say';
+
+use Getopt::Long;
+
+my $order;
+GetOptions( 'order=i' => \$order ) or die;
+
+my @numbers = @ARGV;
+
+foreach my $order ( 1 .. $order ) {
+    @numbers = map { $numbers[ $_ ] - $numbers[ $_ - 1 ] } 1 .. $#numbers;
+    say "$order: " . join(', ', @numbers);
+    last if @numbers == 1;
+}
+
diff --git a/challenge-023/randy-lauen/perl6/ch-1.p6 b/challenge-023/randy-lauen/perl6/ch-1.p6
new file mode 100644
index 0000000000..a239b28586
--- /dev/null
+++ b/challenge-023/randy-lauen/perl6/ch-1.p6
@@ -0,0 +1,27 @@
+#!/usr/bin/env perl6
+
+=begin SYNOPSIS
+
+Task:
+Create a script that prints nth order forward difference series. You should be a 
+able to pass the list of numbers and order number as command line parameters.
+
+Usage:
+    $ perl6 ch-1.p6 --order=1 5 9 2 8 1 6
+
+Notes:
+I don't really understand all the intricacies of the << hyper operator and what 
+the different pointy directions mean, especially when the lists are different 
+sizes. But, after fiddling with it in the perl6 REPL, I managed to find the 
+behavior I was looking for.
+
+=end SYNOPSIS
+
+sub MAIN( Int :$order!, *@numbers where *.elems > 0 ) {
+    for 1 .. $order -> $i {
+        @numbers = @numbers.tail(*-1) >>->> @numbers;
+        say "$i: @numbers.join(', ')";
+        last if @numbers.elems == 1;
+    }
+}
+
diff --git a/challenge-023/randy-lauen/perl6/ch-2.p6 b/challenge-023/randy-lauen/perl6/ch-2.p6
new file mode 100644
index 0000000000..3669bfafa6
--- /dev/null
+++ b/challenge-023/randy-lauen/perl6/ch-2.p6
@@ -0,0 +1,53 @@
+#!/usr/bin/env perl6
+
+=begin SYNOPSIS
+
+Task:
+Create a script that prints Prime Decomposition of a given number. The prime decomposition of a number is 
+defined as a list of prime numbers which when all multiplied together, are equal to that number. For example, 
+the Prime decomposition of 228 is 2,2,3,19 as 228 = 2 * 2 * 3 * 19.
+
+Usage:
+    $ perl6 ch-2.p6 228
+    $ perl6 ch-2.p6 --test
+
+Notes:
+I used the algorithm described here: https://www.geeksforgeeks.org/print-all-prime-factors-of-a-given-number/ 
+
+=end SYNOPSIS
+
+sub my-prime-factors( $n is copy ) {
+    my @factors;
+    while $n %% 2 {
+        @factors.push: 2;
+        $n /= 2;
+    }
+    for 3, 5 ... sqrt($n) -> $i {
+        while $n %% $i {
+            @factors.push: $i;
+            $n /= $i;
+        }
+    }
+    @factors.push: $n if $n > 2;
+
+    return @factors;
+}
+
+
+multi MAIN( Int $input where * > 0 ) {
+    my @factors = my-prime-factors( $input );
+    say @factors.elems
+        ?? @factors.join(', ')
+        !! "No prime factors for: $input";
+    ;
+}
+
+
+multi MAIN( Bool :$test! ) {
+    use Test;
+    for 1 .. 1000 -> $n {
+        say "$n: " ~ my-prime-factors($n).join(', ');
+    }
+}
+
+
-- 
cgit