10 files changed, 244 insertions, 132 deletions
diff --git a/challenge-261/ash/raku/ch-1.raku b/challenge-261/ash/raku/ch-1.raku
new file mode 100644
index 0000000000..1c6a73c9ac
--- /dev/null
+++ b/challenge-261/ash/raku/ch-1.raku
@@ -0,0 +1,19 @@
+# Solution to the Task 1 of The Weekly Challenge 261
+# https://theweeklychallenge.org/blog/perl-weekly-challenge-261/#TASK1
+
+# Test run:
+# $ raku ch-1.raku
+# 36
+# 9
+# 0
+
+my @tests = 
+    (1, 2, 3, 45),
+    (1, 12, 3),
+    (1, 2, 3, 4);
+
+for @tests -> @test {
+    my $sum = [+] @test;
+    my $dig = [+]((@test.map: *.comb).flat);
+    say ($dig - $sum).abs;
+}
diff --git a/challenge-261/ash/raku/ch-2.raku b/challenge-261/ash/raku/ch-2.raku
new file mode 100644
index 0000000000..6864850b42
--- /dev/null
+++ b/challenge-261/ash/raku/ch-2.raku
@@ -0,0 +1,20 @@
+# Solution to the Task 2 of The Weekly Challenge 261
+# https://theweeklychallenge.org/blog/perl-weekly-challenge-261/#TASK2
+
+# Test run:
+# $ raku ch-2.raku
+# 24
+# 8
+# 2
+
+my @tests = 
+    ((5,3,6,1,12), 3),
+    ((1,2,4,3), 1),
+    ((5,6,7), 2);
+
+for @tests -> (@ints, $start is copy) {
+    my $ints = @ints.Bag;
+
+    $start *= 2 while $ints{$start};
+    say $start;
+}
diff --git a/challenge-261/feng-chang/raku/ch-1.raku b/challenge-261/feng-chang/raku/ch-1.raku
new file mode 100755
index 0000000000..b913f2f35c
--- /dev/null
+++ b/challenge-261/feng-chang/raku/ch-1.raku
@@ -0,0 +1,5 @@
+#!/bin/env raku
+
+unit sub MAIN(*@ints);
+
+put @ints.sum - @ints».comb».sum.sum;
diff --git a/challenge-261/feng-chang/raku/ch-2.raku b/challenge-261/feng-chang/raku/ch-2.raku
new file mode 100755
index 0000000000..fbb2ac591f
--- /dev/null
+++ b/challenge-261/feng-chang/raku/ch-2.raku
@@ -0,0 +1,7 @@
+#!/bin/env raku
+
+unit sub MAIN(*@ints);
+
+my $start = @ints.pop;
+$start *= 2 while @ints.grep($start);
+put $start;
diff --git a/challenge-261/feng-chang/raku/test.raku b/challenge-261/feng-chang/raku/test.raku
new file mode 100755
index 0000000000..d78a96d7db
--- /dev/null
+++ b/challenge-261/feng-chang/raku/test.raku
@@ -0,0 +1,25 @@
+#!/bin/env raku
+
+# The Weekly Challenge 261
+use Test;
+
+sub pwc-test(Str:D $script, Bool :$deeply? = False, *@input) {
+    my ($expect, $assertion) = @input.splice(*-2, 2);
+    my $p = run $script, |@input, :out;
+    if $deeply {
+        is-deeply $p.out.slurp(:close).chomp.words.Bag, $expect, $assertion;
+    } else {
+        is $p.out.slurp(:close).chomp, $expect, $assertion;
+    }
+}
+
+# Task 1, Element Digit Sum
+pwc-test './ch-1.raku', <1 2 3 45>,          36, 'Element Digit Sum: (1,2,3,45)           => 36';
+pwc-test './ch-1.raku', <1 12 3>,             9, 'Element Digit Sum: (1,12,3)             => 9';
+pwc-test './ch-1.raku', <1 2 3 4>,            0, 'Element Digit Sum: (1,2,3,4)            => 0';
+pwc-test './ch-1.raku', <236 416 336 350>, 1296, 'Element Digit Sum: (236, 416, 336, 350) => 1296';
+
+# Task 2, Multiply by Two
+pwc-test './ch-2.raku', <5 3 6 1 12>, 3, 24, 'Multiply by Two: @ints=(5,3,6,1,12), $start=3 => 24';
+pwc-test './ch-2.raku', <1 2 4 3>,    1,  8, 'Multiply by Two: @ints=(1,2,4,3),    $start=1 => 8';
+pwc-test './ch-2.raku', <5 6 7>,      2,  2, 'Multiply by Two: @ints=(5,6,7),      $start=2 => 2';
diff --git a/challenge-261/mark-anderson/blog-2.md b/challenge-261/mark-anderson/blog-2.md
deleted file mode 100644
index 55b5699cf5..0000000000
--- a/challenge-261/mark-anderson/blog-2.md
+++ /dev/null
@@ -1,132 +0,0 @@
-# Weekly Challenge #260
-
-### Task 2: Dictionary Rank
-**Submitted by: Mark Anderson**
-
-You are given a word, ```$word```.
-
-Write a script to compute the dictionary rank of the given word.
-
-#### Example 1
-```
-Input: $word = 'CAT'
-Output: 3
-
-All possible combinations of the letters:
-CAT, CTA, ATC, TCA, ACT, TAC
-
-Arrange them in alphabetical order:
-ACT, ATC, CAT, CTA, TAC, TCA
-
-CAT is the 3rd in the list.
-Therefore the dictionary rank of CAT is 3.
-```
-
-#### Example 2
-```
-Input: $word = 'GOOGLE'
-Output: 88
-```
-
-#### Example 3
-```
-Input: $word = 'SECRET'
-Output: 255
-```
-
----
-
-### Solution
-
-One approach is to create all permutations, sort them, and find the index of ```$word```.
-
-This is fine for short words but there's a better solution for long words.
-
-There are numerous videos on youtube explaining the algorithm - I think this a good one [https://www.youtube.com/watch?v=-MpL0X3AHAs](https://www.youtube.com/watch?v=-MpL0X3AHAs)
-
-Here's the gist of the algorithm:
-
-1. Find the rank of each letter.
-
-   ```
-   G O O G L E
-   1 3 3 1 2 0
-   ```
-
-2. For each letter, find the number of letters to its right that have a lower rank.
-
-   ```
-   G O O G L E
-   1 3 3 1 1 0
-   ```
-
-3. For each letter, take the number of repeating letters from that letter to the end of the string.
-   Take the factorial of each result and multiply them together.
-   
-   ```  
-     G    O   O  G  L  E
-   2!*2!  2!  1! 1! 1! 1!
-   ```
-
-   Starting with the first letter, there are 2 Gs and 2 Os so we end up with 2!*2!.
-   The next letter is O. From that letter to the end of the string there is just the repeating O so we end up with 2!
-   and so on.
-   
-4. Take the terms from step 2 and divide them by the terms from step 3.
- 
-   ```
-    G    O    O   G   L    E
-   1/4  3/2  3/1 1/1 1/1  0/1
-   ```
-
-5. Create the sequence ```$word```.end...0 and take the factorial of each term.
-
-   ```
-   G  O  O  G  L  E
-   5! 4! 3! 2! 1! 0!
-   ```
-   
-6. Multipy the terms from step 4 with the terms from step 5.
-
-   ```
-     G       O       O     G    L    E
-   120/4  (3*24)/2  3*6   1*2  1*1  0*1
-   ```
-   
-7. Sum the terms from step 6 and add 1 for a result of 88.
-   ```
-   G    O    O    G   L   E
-   30 + 36 + 18 + 2 + 1 + 0 + 1 = 88
-   ```
-### My translation to Raku:
-
-```
-#!/usr/bin/env raku
-use experimental :cached;
-
-say rank('google');
-
-sub postfix:<!>($n) is cached { [*] 1..$n }
-
-sub rank($word)
-{
-    my @w = $word.comb;
-    my @ranks = @w.sort.squish.antipairs.Map{@w}; 
-    my $bag = @ranks.BagHash;
-
-    my @n = gather for @ranks -> $r
-    {
-        my @less-than = $bag.keys.grep(* < $r);
-        take ([+] $bag{@less-than}) / ([*] $bag.values>>!);
-        $bag{$r}--
-    }
-        
-    1 + [+] @n Z* (@ranks.end...0)>>!
-}
-```
-
-[The full program.](https://github.com/manwar/perlweeklychallenge-club/blob/master/challenge-260/mark-anderson/raku/ch-2.raku)
-
-Thank you for reading my solution to the [Weekly Challenge #260 Task #2.](https://theweeklychallenge.org/blog/perl-weekly-challenge-260/)
-
-*-Mark Anderson*
diff --git a/challenge-261/mark-anderson/raku/ch-1.raku b/challenge-261/mark-anderson/raku/ch-1.raku
new file mode 100644
index 0000000000..c1144ce45b
--- /dev/null
+++ b/challenge-261/mark-anderson/raku/ch-1.raku
@@ -0,0 +1,12 @@
+#!/usr/bin/env raku
+use Test;
+
+is element-digit-sum(1,2,3,45),             36;
+is element-digit-sum(1,12,3),                9;
+is element-digit-sum(1,2,3,4),               0;
+is element-digit-sum(236,416,336,350),    1296;
+
+sub element-digit-sum(+@ints)
+{
+    abs ([+] @ints) - [+] @ints.comb(/<digit>/)
+}
diff --git a/challenge-261/mark-anderson/raku/ch-2.raku b/challenge-261/mark-anderson/raku/ch-2.raku
new file mode 100644
index 0000000000..8254214c62
--- /dev/null
+++ b/challenge-261/mark-anderson/raku/ch-2.raku
@@ -0,0 +1,10 @@
+#!/usr/bin/env raku
+use Test;
+
+is multiply-by-two([5,3,6,1,12], 3), 24;
+is multiply-by-two([1,2,4,3], 1),     8;
+is multiply-by-two([5,6,7], 2),       2;
+
+multi multiply-by-two(@i, $s)               { samewith(@i.BagHash, $s)               }
+multi multiply-by-two($b, $s)               { return $s                              }
+multi multiply-by-two($b, $s where ?$b{$s}) { $b{(0..$s)}:delete; samewith($b, $s*2) }
diff --git a/challenge-261/peter-meszaros/perl/ch-1.pl b/challenge-261/peter-meszaros/perl/ch-1.pl
new file mode 100755
index 0000000000..976027a7f6
--- /dev/null
+++ b/challenge-261/peter-meszaros/perl/ch-1.pl
@@ -0,0 +1,74 @@
+#!/usr/bin/env perl
+#
+#
+# You are given an array of integers, @ints.
+# 
+# Write a script to evaluate the absolute difference between element and digit
+# sum of the given array.
+# Example 1
+# 
+# Input: @ints = (1,2,3,45)
+# Output: 36
+# 
+# Element Sum: 1 + 2 + 3 + 45 = 51
+# Digit Sum: 1 + 2 + 3 + 4 + 5 = 15
+# Absolute Difference: | 51 - 15 | = 36
+# 
+# Example 2
+# 
+# Input: @ints = (1,12,3)
+# Output: 9
+# 
+# Element Sum: 1 + 12 + 3 = 16
+# Digit Sum: 1 + 1 + 2 + 3 = 7
+# Absolute Difference: | 16 - 7 | = 9
+# 
+# Example 3
+# 
+# Input: @ints = (1,2,3,4)
+# Output: 0
+# 
+# Element Sum: 1 + 2 + 3 + 4 = 10
+# Digit Sum: 1 + 2 + 3 + 4 = 10
+# Absolute Difference: | 10 - 10 | = 0
+# 
+# Example 4
+# 
+# Input: @ints = (236, 416, 336, 350)
+# Output: 1296
+# 
+
+use strict;
+use warnings;
+use Test2::V0 -no_srand => 1;
+use Data::Dumper;
+
+my $cases = [
+	[1, 2, 3, 45],
+	[1, 12, 3],
+	[1, 2, 3, 4],
+	[236, 416, 336, 350],
+];
+
+sub element_digit_sum
+{
+	my $l = shift;
+
+	my $elem_sum = 0;
+	my $digi_sum = 0;
+
+	for my $e (@$l) {
+		$elem_sum += $e;
+		$digi_sum += $_ for split('', $e);
+	}
+
+	return abs($elem_sum - $digi_sum);
+}
+
+is(element_digit_sum($cases->[0]),   36, 'Example 1');
+is(element_digit_sum($cases->[1]),    9, 'Example 2');
+is(element_digit_sum($cases->[2]),    0, 'Example 3');
+is(element_digit_sum($cases->[3]), 1296, 'Example 4');
+done_testing();
+
+exit 0;
diff --git a/challenge-261/peter-meszaros/perl/ch-2.pl b/challenge-261/peter-meszaros/perl/ch-2.pl
new file mode 100755
index 0000000000..1cc344c748
--- /dev/null
+++ b/challenge-261/peter-meszaros/perl/ch-2.pl
@@ -0,0 +1,72 @@
+#!/usr/bin/env perl
+#
+# You are given an array of integers, @ints and an integer $start..
+# 
+# Write a script to do the followings:
+# 
+# a) Look for $start in the array @ints, if found multiply the number by 2
+# b) If not found stop the process otherwise repeat
+# 
+# In the end return the final value.
+# Example 1
+# 
+# Input: @ints = (5,3,6,1,12) and $start = 3
+# Output: 24
+# 
+# Step 1: 3 is in the array so 3 x 2 = 6
+# Step 2: 6 is in the array so 6 x 2 = 12
+# Step 3: 12 is in the array so 12 x 2 = 24
+# 
+# 24 is not found in the array so return 24.
+# 
+# Example 2
+# 
+# Input: @ints = (1,2,4,3) and $start = 1
+# Output: 8
+# 
+# Step 1: 1 is in the array so 1 x 2 = 2
+# Step 2: 2 is in the array so 2 x 2 = 4
+# Step 3: 4 is in the array so 4 x 2 = 8
+# 
+# 8 is not found in the array so return 8.
+# 
+# Example 3
+# 
+# Input: @ints = (5,6,7) and $start = 2
+# Output: 2
+# 
+# 2 is not found in the array so return 2.
+# 
+
+use strict;
+use warnings;
+use Test2::V0 -no_srand => 1;
+use Data::Dumper;
+
+my $cases = [
+	[[5, 3, 6, 1, 12], 3],
+	[[1, 2, 4, 3],     1],
+	[[5, 6, 7],        2],
+];
+
+sub multiply_by_two
+{
+	my ($l, $s) = $_[0]->@*;
+
+	START:
+	for my $i (@$l) {
+		if ($i == $s) {
+			$s *= 2;
+ 			goto START;
+		}
+	}
+	return $s;
+}
+
+is(multiply_by_two($cases->[0]), 24, 'Example 1');
+is(multiply_by_two($cases->[1]),  8, 'Example 2');
+is(multiply_by_two($cases->[2]),  2, 'Example 3');
+done_testing();
+
+exit 0;
+