From 4238efb2ed473fbb06b912b3c2c0eac7652d82cf Mon Sep 17 00:00:00 2001
From: Steven Wilson <steven1170@zoho.eu>
Date: Wed, 3 Jul 2019 22:25:27 +0100
Subject: add blog and benchmarking

---
 challenge-015/steven-wilson/blog.txt           |  1 +
 challenge-015/steven-wilson/perl5/bmark-ch2.pl | 58 ++++++++++++++++++++++++++
 2 files changed, 59 insertions(+)
 create mode 100644 challenge-015/steven-wilson/blog.txt
 create mode 100644 challenge-015/steven-wilson/perl5/bmark-ch2.pl

diff --git a/challenge-015/steven-wilson/blog.txt b/challenge-015/steven-wilson/blog.txt
new file mode 100644
index 0000000000..ede4c2e597
--- /dev/null
+++ b/challenge-015/steven-wilson/blog.txt
@@ -0,0 +1 @@
+http://tilde.town/~wlsn/pwc015.html
diff --git a/challenge-015/steven-wilson/perl5/bmark-ch2.pl b/challenge-015/steven-wilson/perl5/bmark-ch2.pl
new file mode 100644
index 0000000000..734bed0017
--- /dev/null
+++ b/challenge-015/steven-wilson/perl5/bmark-ch2.pl
@@ -0,0 +1,58 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+use List::MoreUtils qw/ first_index /;;
+use Benchmark::Forking qw/ cmpthese /;
+
+my @alphabet = ("A".."Z");
+
+cmpthese(-10, {
+    'initial_encode' => sub{
+        my ( $plaintext, $keyword ) = ("MMEZQTBJDGNQKYPURWZMWOIUOC", "LEMON");
+        my $cyphertext;
+        for my $i (0..((length $plaintext) - 1)){
+            (my $mi) = grep { $alphabet[$_] eq substr($plaintext, $i, 1) } (0..@alphabet-1);
+            (my $ki) = grep { $alphabet[$_] eq substr($keyword, ($i % length $keyword), 1)} (0..@alphabet-1);
+            $cyphertext .= $alphabet[($mi + $ki) % 26];
+        }
+        return $cyphertext;
+    },
+
+    'substr_out_grep' => sub{
+        my ( $plaintext, $keyword ) = ("MMEZQTBJDGNQKYPURWZMWOIUOC", "LEMON");
+        my $cyphertext;
+        for my $i (0..((length $plaintext) - 1)){
+            my $plaintext_chr = substr($plaintext, $i, 1);
+            my $keyword_chr   = substr($keyword, ($i % length $keyword), 1);
+            (my $mi) = grep { $alphabet[$_] eq $plaintext_chr } (0..@alphabet-1);
+            (my $ki) = grep { $alphabet[$_] eq $keyword_chr } (0..@alphabet-1);
+            $cyphertext .= $alphabet[($mi + $ki) % 26];
+        }
+        return $cyphertext;
+    },
+
+    'use_first_index' => sub{
+        my ( $plaintext, $keyword ) = ("MMEZQTBJDGNQKYPURWZMWOIUOC", "LEMON");
+        my $cyphertext;
+        for my $i (0..((length $plaintext) - 1)){
+            my $plaintext_chr = substr($plaintext, $i, 1);
+            my $keyword_chr   = substr($keyword, ($i % length $keyword), 1);
+            (my $mi) = first_index { $alphabet[$_] eq $plaintext_chr } (0..@alphabet-1);
+            (my $ki) = first_index { $alphabet[$_] eq $keyword_chr } (0..@alphabet-1);
+            $cyphertext .= $alphabet[($mi + $ki) % 26];
+        }
+        return $cyphertext;
+    },
+
+    'use_ord_chr' => sub{
+        my ( $plaintext, $keyword ) = ("MMEZQTBJDGNQKYPURWZMWOIUOC", "LEMON");
+        my $cyphertext;
+        for my $i (0..((length $plaintext) - 1)){
+            my $mi = ord( substr( $plaintext, $i, 1 ) ) - 65;
+            my $ki = ord( substr( $keyword, ($i % length $keyword), 1)) - 65;
+            $cyphertext .= chr((($mi + $ki) % 26) + 65);
+        }
+        return $cyphertext;
+    },
+});
-- 
cgit