1 files changed, 148 insertions, 0 deletions
diff --git a/challenge-081/athanasius/raku/ch-2.raku b/challenge-081/athanasius/raku/ch-2.raku
new file mode 100644
index 0000000000..c5d2bc7774
--- /dev/null
+++ b/challenge-081/athanasius/raku/ch-2.raku
@@ -0,0 +1,148 @@
+use v6d;
+
+###############################################################################
+=begin comment
+
+Perl Weekly Challenge 081
+=========================
+
+Task #2
+-------
+*Frequency Sort*
+
+Submitted by: Mohammad S Anwar
+
+You are given file named input.
+
+Write a script to find the frequency of all the words.
+
+It should print the result as first column of each line should be the frequency
+of the the word followed by all the words of that frequency arranged in lexico-
+graphical order. Also sort the words in the ascending order of frequency.
+
+INPUT file
+
+ West Side Story
+
+ The award-winning adaptation of the classic romantic tragedy "Romeo and
+ Juliet". The feuding families become two warring New York City gangs, the
+ white Jets led by Riff and the Latino Sharks, led by Bernardo. Their hatred
+ escalates to a point where neither can coexist with any form of understanding.
+ But when Riff's best friend (and former Jet) Tony and Bernardo's younger
+ sister Maria meet at a dance, no one can do anything to stop their love. Maria
+ and Tony begin meeting in secret, planning to run away. Then the Sharks and
+ Jets plan a rumble under the highway--whoever wins gains control of the
+ streets. Maria sends Tony to stop it, hoping it can end the violence. It goes
+ terribly wrong, and before the lovers know what's happened, tragedy strikes
+ and doesn't stop until the climactic and heartbreaking ending.
+
+NOTE
+
+For the sake of this task, please ignore the following in the input file:
+
+ . " ( ) , 's --
+
+OUTPUT
+
+ 1 But City It Jet Juliet Latino New Romeo Side Story Their Then West York
+ adaptation any anything at award-winning away become before begin best classic
+ climactic coexist control dance do doesn't end ending escalates families
+ feuding form former friend gains gangs goes happened hatred heartbreaking
+ highway hoping in know love lovers meet meeting neither no one plan planning
+ point romantic rumble run secret sends sister streets strikes terribly their
+ two under understanding until violence warring what when where white whoever
+ wins with wrong younger
+
+ 2 Bernardo Jets Riff Sharks The by it led tragedy
+
+ 3 Maria Tony a can of stop
+
+ 4 to
+
+ 9 and the
+
+=end comment
+###############################################################################
+
+#--------------------------------------#
+# Copyright © 2020 PerlMonk Athanasius #
+#--------------------------------------#
+
+my constant $DEFAULT-INPUT-FILE = 'WestSideStory.txt';
+
+#------------------------------------------------------------------------------
+BEGIN
+#------------------------------------------------------------------------------
+{
+    "\nChallenge 081, Task #2: Frequency Sort (Raku)".put;
+}
+
+##=============================================================================
+sub MAIN
+(
+    Str:D $input where *.IO.f = $DEFAULT-INPUT-FILE          #= Input file name
+)
+##=============================================================================
+{
+    # (1) Read in and edit the input text
+
+    my Str $text = $input.IO.slurp;
+
+    # The text is first edited by replacing trailing 's and _ with spaces, then
+    # any remaining apostrophes are converted to underscores. This is done
+    # because \w matches the underscore character but not the apostrophe: which
+    # makes it easy to identify "words" using the zero-width assertions « and »
+    # that match on word boundaries (\W\w and \w\W). Note: It is not necessary
+    # to remove the other non-word characters [."(),] from the text, as these
+    # are automatically excluded by the match logic of the regex below.
+
+    $text ~~ s:g/ \'s » / /;
+    $text ~~ s:g/  _    / /;
+    $text ~~ s:g/ \'    /_/;
+
+    # (2) Create a dictionary of words (keys) and their frequencies (values)
+
+    my UInt %by-word;
+
+    for $text ~~ m:g/ « (\w+?) » / -> Match $match
+    {
+        my Str $word =  $match.Str;
+
+        # Once a word has been identified, its apostrophes (if any) are
+        # restored, then it is recorded in the dictionary
+
+        $word ~~ s:g/ _ /'/;
+
+        ++%by-word{ $word };
+    }
+
+    # (3) Create a reverse dictionary of frequencies (keys) and arrays of words
+    #     (values)
+
+    my Array[Str] %by-freq;
+
+    for %by-word.kv -> Str $word, UInt $freq
+    {
+        %by-freq{ $freq }.push: $word;
+    }
+
+    # (4) Output frequencies (in ascending numerical order) together with their
+    #     associated words (in ascending lexicographical order)
+
+    for %by-freq.keys.map( { .UInt }).sort -> UInt $freq
+    {
+        "\n%d %s\n".printf: $freq, %by-freq{ $freq }.sort.join: ' ';
+    }
+}
+
+#------------------------------------------------------------------------------
+sub USAGE()
+#------------------------------------------------------------------------------
+{
+    my Str $usage = $*USAGE;
+
+    $usage ~~ s/ ($*PROGRAM-NAME) /raku $0/;
+    $usage.put;
+}
+
+###############################################################################