From ff4378f2627cbf3c3674110dbe7d27372e63d651 Mon Sep 17 00:00:00 2001
From: Jörg Sommrey <28217714+jo-37@users.noreply.github.com>
Date: Mon, 18 Oct 2021 13:10:19 +0200
Subject: Solution to task 1

---
 challenge-135/jo-37/perl/ch-1.pl | 64 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100755 challenge-135/jo-37/perl/ch-1.pl

diff --git a/challenge-135/jo-37/perl/ch-1.pl b/challenge-135/jo-37/perl/ch-1.pl
new file mode 100755
index 0000000000..e8049ba672
--- /dev/null
+++ b/challenge-135/jo-37/perl/ch-1.pl
@@ -0,0 +1,64 @@
+#!/usr/bin/perl -s
+
+use v5.16;
+use Test2::V0;
+use experimental 'signatures';
+
+our ($tests, $examples);
+
+run_tests() if $tests || $examples;	# does not return
+
+die <<EOS unless @ARGV;
+usage: $0 [-examples] [-tests] [--] [N]
+
+-examples
+    run the examples from the challenge
+ 
+-tests
+    run some tests
+
+N
+    Number. Use '-- -N' for negative numbers.
+
+EOS
+
+
+### Input and Output
+
+say middle_digits(shift);
+
+
+### Implementation
+
+sub middle_digits ($n) {
+    $n = int abs $n;
+    my $l = length $n;
+    die "even number of digits\n" unless $l % 2;
+    die "too short\n" unless $l >= 3;
+    substr $n, ($l - 3) / 2, 3;
+}
+
+
+### Examples and tests
+
+sub run_tests {
+    SKIP: {
+        skip "examples" unless $examples;
+
+        is middle_digits(1234567), 345, 'example 1';
+        is middle_digits(-123), 123, 'example 2';
+        like dies {middle_digits(1)}, qr(too short), 'example 3';
+        like dies {middle_digits(12)}, qr(even number of digits), 'example 4';
+    }
+
+    SKIP: {
+        skip "tests" unless $tests;
+
+        is middle_digits('0012345'), 234, 'ignore leading zeros';
+        is middle_digits(12345.67), 234, 'force float to integer';
+        is middle_digits(-12345.67), 234, 'force negative float to integer';
+	}
+
+    done_testing;
+    exit;
+}
-- 
cgit 


From a6a7d5953abd21a36f80e76995a34a9e8c790e30 Mon Sep 17 00:00:00 2001
From: Jörg Sommrey <28217714+jo-37@users.noreply.github.com>
Date: Mon, 18 Oct 2021 13:10:31 +0200
Subject: Solution to task 2

---
 challenge-135/jo-37/perl/ch-2.pl | 114 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 114 insertions(+)
 create mode 100755 challenge-135/jo-37/perl/ch-2.pl

diff --git a/challenge-135/jo-37/perl/ch-2.pl b/challenge-135/jo-37/perl/ch-2.pl
new file mode 100755
index 0000000000..4e501793e2
--- /dev/null
+++ b/challenge-135/jo-37/perl/ch-2.pl
@@ -0,0 +1,114 @@
+#!/usr/bin/perl -s
+
+use v5.18;
+use Test2::V0;
+use List::MoreUtils 'reduce_0';
+use experimental qw(postderef regex_sets);
+
+our ($tests, $examples);
+
+run_tests() if $tests || $examples;	# does not return
+
+die <<EOS unless @ARGV;
+usage: $0 [-examples] [-tests] [S]
+
+-examples
+    run the examples from the challenge
+ 
+-tests
+    run some tests
+
+S
+    validate SEDOL code S.
+
+EOS
+
+
+### Input and Output
+
+say 0 + validate_sedol(shift);
+
+
+### Implementation
+
+# To validate a SEDOL code, the check digit need not be calculated.  
+#
+# As the Wiki article states, all new SEDOLs start with a letter.
+# Furthermore, the formula for the checksum - always producing a digit -
+# restricts the final character.
+# Checking:
+# - seven digits
+# or
+# - no digit at start
+# - six digits or uppercase vowels
+# - followed by one digit
+# and
+# - weighted "digit" sum is a multiple of 10
+#
+# There are no special requirements for the character encoding in use.
+
+BEGIN {
+    my @weight = (1, 3, 1, 7, 3, 9, 1);
+    (\my %value)->@{0 .. 9, 'A' .. 'Z'} = (0 .. 35);
+
+    sub validate_sedol {
+        local $_ = shift;
+
+        /^ (?:
+                \p{Digit} {7}
+            |
+                (?! \p{Digit} )
+                (?[ \p{Digit} + \p{PosixUpper} - [AEIOU] ]) {6}
+                \p{Digit}
+            ) \z/ax &&
+        !((reduce_0 {$a += $weight[$_] * $value{$b}} /./g) % 10);
+    }
+}
+
+
+### Examples and tests
+
+sub run_tests {
+    SKIP: {
+        skip "examples" unless $examples;
+
+        is validate_sedol('2936921'), T(), 'example 1';
+        is validate_sedol('1234567'), F(), 'example 2';
+        is validate_sedol('B0YBKL9'), T(), 'example 3';
+    }
+
+    SKIP: {
+        skip "tests" unless $tests;
+
+        is validate_sedol('0263494'), T(), 'BAE from Wiki';
+        is validate_sedol('B000009'), T(), 'first new code';
+        is validate_sedol('100001'),  F(), 'old too short';
+        is validate_sedol('B00001'),  F(), 'new too short';
+        is validate_sedol('10000090'), F(), 'old too long';
+        is validate_sedol('B0000090'), F(), 'new too long';
+        is validate_sedol('E000006'), F(), 'invalid char';
+        is validate_sedol('B00000J'), F(), 'alpha checksum';
+        is validate_sedol('1000009'), T(), 'weight at 0';
+        is validate_sedol('0100007'), T(), 'weight at 1';
+        is validate_sedol('0010009'), T(), 'weight at 2';
+        is validate_sedol('0001003'), T(), 'weight at 3';
+        is validate_sedol('0000107'), T(), 'weight at 4';
+        is validate_sedol('0000011'), T(), 'weight at 5';
+        is validate_sedol('BB00006'), T(), 'letters';
+        is validate_sedol('B100006'), T(), 'mixed';
+        is validate_sedol('0000000'), T(), 'checksum is linear';
+        is validate_sedol('ZZZZZZ0'), T(), 'this is nice';
+        is validate_sedol('1111111'), F(), 'old counterexample';
+        is validate_sedol('BBBBBB1'), F(), 'new counterexample';
+        is validate_sedol('0B00007'), F(), 'letter with starting digit';
+        is validate_sedol('xB000009'), F(), 'anchor at beginning / old';
+        is validate_sedol('x0000000'), F(), 'anchor at beginning / new';
+        is validate_sedol('0000000x'), F(), 'anchor at end / old';
+        is validate_sedol('B000009x'), F(), 'anchor at end / new';
+        ok no_warnings {validate_sedol('Ä000000')}, 'exclude non-ASCII';
+
+	}
+
+    done_testing;
+    exit;
+}
-- 
cgit