The Weekly Challenge: 371

TABLE OF CONTENTS

  1. HEADLINES

  2. SPONSOR

  3. RECAP

  4. PERL REVIEW

  5. RAKU REVIEW

  6. CHART

  7. NEW MEMBERS

  8. GUESTS

  9. TASK #1: Missing Letter

10. TASK #2: Subset Equilibrium

HEADLINES

Welcome to the Week #371 of The Weekly Challenge.

Welcome aboard, John Chambers, and thanks for your first contributions in Perl.

Thank you, Abigail, for the contributions and blog posts: Popular Word and Scramble String.

Below is my contributions to the Task #1 of Week #370.

Perl: source code

sub most_popular {
    my ($para, @banned) = @_;

    my %b = map { lc $_ => 1 } @banned;
    my %f;
    $f{$_}++ for grep { !$b{$_} } map { lc } $para =~ /[a-zA-Z]+/g;
    return reduce { $f{$b} > $f{$a} ? $b : $a } keys %f;
}

Raku: source code

sub most-popular($para, *@banned) {
    my $b = @banned.map(*.lc).Set;
    my %f = $para.lc.comb(/<[a..z]>+/).grep({ $_ ∉ $b }).Bag;
    return %f.pairs.sort({ -.value }).head.key;
}

Python: source code

def most_popular(paragraph, banned):
    banned_set = {word.lower() for word in banned}
    words = re.findall(r'[a-z]+', paragraph.lower())
    counts = Counter(w for w in words if w not in banned_set)
    return counts.most_common(1)[0][0]

Thank you Team PWC, once again.

Happy Hacking!!

Last 5 weeks mainstream contribution stats. Thank you Team PWC for your support and encouragements.

Last 5 weeks guest contribution stats. Thank you each and every guest contributors for your time and efforts.

TOP 10 Guest Languages

Do you see your favourite language in the Top #10? If not then why not contribute regularly and make it to the top.

 1. Python     (4345)
 2. Rust       (1143)
 3. C          (1018)
 3. Ruby       (895)
 5. Haskell    (889)
 6. Lua        (882)
 7. C++        (712)
 8. Go         (680)
 9. JavaScript (635)
10. Java       (532)

Blogs with Creative Title

1. Popular Scramble by Arne Sommer.

2. Scramble On, Scramblin’ Man by Bob Lied.

3. Scrambled Bans by Jorg Sommrey.

4. Scrambling Back and Forth by Matthias Muth.

5. The scramble can not stop you / from becoming popu-ler… lar by Packy Anderson.

6. Words and more words by Peter Campbell Smith.

7. Popular Scramble by Roger Bell_West.

8. Popular Scrambling by Simon Green.

GitHub Repository Stats

1. Commits: 49,284 (+141)

2. Pull Requests: 14,004 (+39)

3. Contributors: 278 (+1)

4. Fork: 348 (+2)

5. Stars: 212 (+2)

SPONSOR

With start of Week #355, we have a new sponsor Marc Perry until the end of year 2026. Having said we are looking for more sponsors so that we can go back to weekly winner. If anyone interested please get in touch with us at perlweeklychallenge@yahoo.com. Thanks for your support in advance. You can find more informations here.

RECAP

Quick recap of The Weekly Challenge - 370 by Mohammad Sajid Anwar.

PERL REVIEW

If you missed any past reviews then please check out the collection.

RAKU REVIEW

If you missed any past reviews then please check out the collection.

CHART

Please take a look at the charts showing interesting data.

I would like to THANK every member of the team for their valuable suggestions. Please do share your experience with us.

NEW MEMBERS

John Chambers, an experienced Perl hacker joined Team PWC.

Please find out How to contribute?, if you have any doubts.

Please try the excellent tool EZPWC created by respected member Saif Ahmed of Team PWC.

GUESTS

Please check out the guest contributions for the Week #370.

Please find past solutions by respected guests. Please share your creative solutions in other languages.

Task 1: Missing Letter

Submitted by: Reinier Maliepaard

You are given a sequence of 5 lowercase letters, with one letter replaced by ‘?’. Each letter maps to its position in the alphabet (‘a = 1’, ‘b = 2’, …, ‘z = 26’). The sequence follows a repeating pattern of step sizes between consecutive letters. The pattern is either a constant step (e.g., ‘+2, +2, +2, +2’) or a simple alternating pattern of two distinct steps (e.g., ‘+2, +3, +2, +3’).

Example 1

Input: $seq = qw(a c ? g i)
Output: e

The pattern of the sequence is +2,+2,+2,+2.
1: a
3: c
5: e
7: g
9: i

Example 2

Input: $seq = qw(a d ? j m)
Output: g

The pattern of the sequence is +3,+3,+3,+3.
1: a
4: d
7: g
10: j
13: m

Example 3

Input: $seq = qw(a e ? m q)
Output: i

The pattern of the sequence is +4,+4,+4,+4.
1: a
5: e
9: i
13: m
17: q

Example 4

Input: $seq = qw(a c f ? k)
Output: h

The pattern of the sequence is +2,+3,+2,+3.
1: a
3: c
6: f
8: h
11: k

Example 5

Input: $seq = qw(b e g ? l)
Output: j

The pattern of the sequence is +3,+2,+3,+2.
2: b
5: e
7: g
10: j
12: l

Task 2: Subset Equilibrium

Submitted by: Mohammad Sajid Anwar

You are given an array of numbers.

Write a script to find all subsets where the sum of elements equals the sum of their indices.

Example 1

Input: @nums = (2, 1, 4, 3)
Output: (2, 1), (1, 4), (4, 3), (2, 3)

Subset 1: (2, 1)
Values: 2 + 1 = 3
Positions: 1 + 2 = 3

Subset 2: (1, 4)
Values: 1 + 4 = 5
Positions: 2 + 3 = 5

Subset 3: (4, 3)
Values: 4 + 3 = 7
Positions: 3 + 4 = 7

Subset 4: (2, 3)
Values: 2 + 3 = 5
Positions: 1 + 4 = 5

Example 2

Input: @nums = (3, 0, 3, 0)
Output: (3, 0), (3, 0, 3)

Subset 1: (3, 0)
Values: 3 + 0 = 3
Positions: 1 + 2 = 3

Subset 2: (3, 0, 3)
Values: 3 + 0 + 3 = 6
Positions: 1 + 2 + 3 = 6

Example 3

Input: @nums = (5, 1, 1, 1)
Output: (5, 1, 1)

Subset 1: (5, 1, 1)
Values: 5 + 1 + 1 = 7
Positions: 1 + 2 + 4 = 7

Example 4

Input: @nums = (3, -1, 4, 2)
Output: (3, 2), (3, -1, 4)

Subset 1: (3, 2)
Values: 3 + 2 = 5
Positions: 1 + 4 = 5

Subset 2: (3, -1, 4)
Values: 3 + (-1) + 4 = 6
Positions: 1 + 2 + 3 = 6

Example 5

Input: @nums = (10, 20, 30, 40)
Output: ()

By submitting a response to the challenge you agree that your name or pseudonym, any photograph you supply and any other personal information contained in your submission may be published on this website and the associated mobile app. Last date to submit the solution 23:59 (UK Time) Sunday 3rd May 2026.