From 27a42b2c0c633a11815ea027b69bd8b63a6296e6 Mon Sep 17 00:00:00 2001
From: "Kian-Meng, Ang" <kianmeng@cpan.org>
Date: Sun, 1 Sep 2019 21:00:05 +0800
Subject: Add task 1 & 2 for challenge 023

---
 challenge-023/kian-meng-ang/perl5/ch-1.pl | 47 +++++++++++++++++++++++++++++++
 challenge-023/kian-meng-ang/perl5/ch-2.pl | 36 +++++++++++++++++++++++
 2 files changed, 83 insertions(+)
 create mode 100644 challenge-023/kian-meng-ang/perl5/ch-1.pl
 create mode 100644 challenge-023/kian-meng-ang/perl5/ch-2.pl

diff --git a/challenge-023/kian-meng-ang/perl5/ch-1.pl b/challenge-023/kian-meng-ang/perl5/ch-1.pl
new file mode 100644
index 0000000000..06b7e92295
--- /dev/null
+++ b/challenge-023/kian-meng-ang/perl5/ch-1.pl
@@ -0,0 +1,47 @@
+#!/usr/bin/env perl
+# vi:et:sw=4 ts=4 ft=perl
+
+use strict;
+use warnings;
+use utf8;
+use feature qw(say);
+use constant USAGE => qq|USAGE: perl $0 <order> <n1,n2,...,nN>|;
+use Carp;
+
+my $order = $ARGV[0] || croak USAGE;
+my @seq = split /,/, $ARGV[1] || croak USAGE;
+scalar @seq > $order || croak q|ERROR: Total sequence of number must larger than order|;
+
+my @trace;
+foreach my $o (1 .. $order) {
+    my @nseq;
+    foreach my $s (1 .. scalar @seq - 1) {
+        push @nseq, $seq[$s] - $seq[$s - 1];
+    }
+    push @trace, \@nseq;
+    @seq = @nseq;
+}
+
+foreach (0 .. scalar @trace - 1) {
+    say sprintf q|order:%s seq:%s|, $_ + 1, join q|,|, @{$trace[$_]};
+}
+
+1;
+
+__END__
+
+$ perl ch-1.pl
+USAGE: perl ch-1.pl <order> <n1,n2,...,nN> at ch-1.pl line 10
+
+$ perl ch-1.pl 1
+USAGE: perl ch-1.pl <order> <n1,n2,...,nN> at ch-1.pl line 11.
+
+$ perl ch-1.pl 1 5
+ERROR: Total sequence of number must larger than order at ch-1.pl line 12.
+
+$ perl ch-1.pl 5 5,9,2,8,1,6
+order:1 seq:4,-7,6,-7,5
+order:2 seq:-11,13,-13,12
+order:3 seq:24,-26,25
+order:4 seq:-50,51
+order:5 seq:101
diff --git a/challenge-023/kian-meng-ang/perl5/ch-2.pl b/challenge-023/kian-meng-ang/perl5/ch-2.pl
new file mode 100644
index 0000000000..f3e61b8716
--- /dev/null
+++ b/challenge-023/kian-meng-ang/perl5/ch-2.pl
@@ -0,0 +1,36 @@
+#!/usr/bin/env perl
+# vi:et:sw=4 ts=4 ft=perl
+
+use strict;
+use warnings;
+use utf8;
+use feature qw(say signatures);
+no warnings 'experimental::signatures';
+
+use Carp;
+use ntheory qw(primes);
+
+MAIN: {
+    my $number =  $ARGV[0] || croak 'ERROR: missing number';
+    say sprintf q|Number: %s have prime factors: %s|,
+        $number, join q|,|, prime_factors($number);
+}
+
+sub prime_factors($number) {
+    my $primes = primes(2, $number);
+    my @factors;
+    foreach my $prime (@{$primes}) {
+        while ($number % $prime == 0) {
+            $number = $number / $prime;
+            push @factors, $prime;
+            next if $number == 1;
+        }
+    }
+    return @factors;
+}
+
+1;
+
+__END__
+$ perl ch-2.pl 228
+Number: 228 have prime factors: 2,2,3,19
-- 
cgit