perl5 solution for task2

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diff --git a/challenge-023/randy-lauen/perl5/ch-2.pl b/challenge-023/randy-lauen/perl5/ch-2.pl
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+#!/usr/bin/env perl
+
+=head1 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:
+    $ perl ch-2.pl 228
+
+Notes:
+I used the algorithm described here: https://www.geeksforgeeks.org/print-all-prime-factors-of-a-given-number/ 
+
+=cut
+
+use strict;
+use warnings;
+use feature 'say';
+
+my $num = $ARGV[0] // '';
+die "Must pass an integer > 0 as the first argument\n" unless $num && $num =~ /^\d+$/;
+
+say $num == 1
+    ? "No prime factors for 1"
+    : join(', ', prime_factors( $num ) )
+;
+
+exit 0;
+
+sub prime_factors {
+    my $n = shift;
+
+    my @factors;
+    while ( $n % 2 == 0 ) {
+        push @factors, 2;
+        $n /= 2;
+    }
+    for ( my $i = 3; $i <= sqrt($n); $i += 2 ) {
+        while ( $n % $i == 0 ) {
+            push @factors, $i;
+            $n /= $i;
+        }
+    }
+    push @factors, $n if $n > 2;
+
+    return @factors;
+}
+