The Weekly Challenge: 365

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: Alphabet Index Digit Sum

10. TASK #2: Valid Token Counter

HEADLINES

Welcome to the Week #365 of The Weekly Challenge.

Let us welcome Abigail back. I was pleasantly surprised to see him sharing his knowledge with us again. Thank you for sharing solutions in Awk, Bash, C, Perl, and Python.

Welcome back, beespider, and thanks for your contributions in Uiua.

Thank you, Niels van Dijke, for taking the time to share your contributions with us. Your participation in past few weeks has made a positive impact on the stats. We now have 5 weeks reaching the target in 2026 and another two weeks are very close to achieving it.

Thank you, Paulo Custodio, for your contiuous support and contributions. I can feel the energy you bring, and it motivates me to keep pushing the boundaries.

Thank you, Lubos Kolouch, for your diverse contributions. It is incredible to see such support, I am truly overwhelmed.

In the guest language rankings, I see C moving up to position #5, and giving tough competition to other guest languages. Well done and thank you all C contributors.

Sponsorship Update:

Last week I mentioned that we have a monthly prize pot sponsor but did not reveal the name at that time. Today I am very happy to share it. The sponsor is our newly joined team member Marc Perry. Although he is relatively new to the team, I have known him for a long time, even though we have never met in person. I truly appreciate his generosity and support for the project. Thank you, Marc, for helping make the monthly prizes possible.

Technically, I should have announced the monthly champion earlier, even without the prize money. Nevertheless, it is never too late. Today I am going to announce two champions: one for January and another for February. With great pride, I declare Matthew Neleigh as Champion of the Month for January and Matthias Muth as Champion of the Month for February.

Both have been champions in the past already, i.e. Matthew Neleigh in April 2022 and Matthias Muth in May 2023. Many congratulations to both dedicated team members. I will send you both a personal email regarding the prize money.

By the way, I am still waiting for a response from Mark Anderson, the Champion of the Month for December 2025. I sent the email on 6th March. I know it is very late - my apologies. Please get back to me when you can.

From next month onward, I will try to streamline everything. Promise.

Community Shout-out

Last week, I also shared the new look website with the team. I am grateful to all of you who sent me messages and said nice things about the new look. Even a single word of appreciation fills me with lots of energy. So thank you, Team PWC.

For a long time, I have been thinking about building a mobile app for The Weekly Challenge project, but I always faced obstacles, mainly because I am a hardcore Perl programmer. Unfortunately, Perl is not one of the supported languages for building mobile apps. At that time, I was thinking about making an app for iPhone, as I had the handset. Someone told me the easiest option was to learn Swift first. So I took a bootcamp course on Udemy about building iPhone apps using Swift. I even started sharing weekly challenge solutions in Swift, if you remember.

I also bought a Mac Mini so that I could start developing toy apps and learn the tricks. This was my first Mac machine. All my life, I had never touched a Mac device before. I liked the machine and built around 10 toy apps with the help of the bootcamp course. My twins (9 years old) would get excited every time I showed them the app on my iPhone. Then life took another twist, and I stopped participating completely. The Mac Mini is still sitting on my desk, switched off. Every now and then my wife reminds me about my mobile app project, and I keep avoiding the topic.

Fast forward to today. After the launch of the new look website, I decided to give the mobile app idea another try. While doing the research, I found out that to publish a mobile app for iPhone, I need to be a member of the Apple Developer Program, which costs $99 per year. That put me off immediately because I don’t have the budget for it. However, I didn’t want to scrap the idea completely. So the other option was to build an app for Android devices. Later I found out that for this I only need to make a one-off payment of $25. This is something I can easily afford.

Now the question was: how am I going to build an Android app? Do I have to learn another programming language? After doing a little research, I found that the easiest option is React Native. And it is not that difficult to learn. I am also told that the same codebase can be used to build an app for iPhone.

Now that I had finalised my plan, I started building a simple interface for the weekly challenge. The most difficult part was the chart screen, as you all know how difficult it was when I did the migration earlier. I decided to make the chart simpler for the mobile app but keep the same information.

Since this was my first time, I had to set up my development environment. I downloaded Android Studio and installed a couple of virtual devices to test the app. In five days, I had a working prototype. I used my iPhone to test the app as well. It looked nice on the virtual Android devices too. For the first release, I am only going with the easy portable features from the new look website. In the following releases, I will add more features as I am learning too in the process.

Since I am going to build and support the mobile app, I wanted a dedicated physical Android device. I looked at what was available and found Android phones that were expensive, though still cheaper than Apple phones. My objective is to test the app, not to use it as my primary phone, so I started looking at tablets instead. I found one within my budget - Samsung Galaxy Tab A11. I ordered it on Amazon and the next day the device was in my hands. I started testing the app on it and immediately found an issue: the bottom icon bar was hidden behind the device navigation icons. I quickly fixed it, and everything looked fine.

Now it was time to publish the app on the Play Store. It was not as straightforward as I initially thought. I had to jump through many hoops to get to the point where the app was ready to be reviewed by Google. At that stage, I was told I needed a minimum of 12 real human testers before Google would approve it for live listing.

My first thought was to create 12 new Gmail accounts and use them as testers. It turned out this is not acceptable. Google looks for real Android devices with each tester, and the testing period must last 14 days. If even one person stops testing during this period, the approval may fail and the process must start again.

So now the question is: where do I find 12 real people with Android devices? I have one device myself, but I still need at least 11 more. The only hope I have is to ask Team PWC if they can help me test the app.

I have created a dedicated Google Group email as suggested by the process, just for this purpose. Ideally, I would like 20+ volunteers, in case someone stops halfway through. Please write to me, mohammad.anwar@yahoo.com, if you are willing to be a tester for two weeks. I will then send you a personal invitation from the Google Group email so that Google can monitor how many testers are using the app. Once you become an official tester, you will receive the link to download the app on your Android device.

I request you to please keep the app installed on your device for at least 14 days. You don’t need to use it every hour, but opening it occasionally to browse recent challenges or recaps will help show Google that the app has active engagement.

Thank you all in advance for helping make the first Weekly Challenge mobile app a reality.

Now that I am done with the app development, I feel really tired. I already had a lot of admin work even before the new look website went live. Now I have added more processes to feed additional data into the new look website. On top of that, I now have to manage the mobile app as well. I am excited, but also a little scared. It is still early days, but I am sure with time everything will become smoother.

Below is my contributions to the Task #1 of Week #364.

Perl: source code

sub decrypt_string {
    my $str = shift;

    $str =~ s/(\d{2})#|(\d)/ chr(($1 || $2) + 96) /ge;
    return $str;
}

Raku: source code

sub decrypt-string(Str $str --> Str) {
    return $str.subst(/(\d**2)'#' | (\d)/, { chr(($0 // $1).Int + 96) }, :g);
}

Python: source code

def decrypt_string(s: str) -> str:
    return re.sub(r'(\d{2})#|(\d)', lambda m: chr(int(m.group(1) or m.group(2)) + 96), s)

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     (4215)
 2. Rust       (1119)
 3. Ruby       (877)
 4. Haskell    (873)
 5. C          (863)
 6. Lua        (856)
 7. C++        (700)
 8. Go         (658)
 9. JavaScript (626)
10. Java       (528)

Blogs with Creative Title

1. String Goal by Arne Sommer.

2. Alternate Codes by Jorg Sommrey.

3. substituting strings! by Luca Ferrari.

4. Decrypted “715#15#15#112#": goooal! by Matthias Muth.

5. Andrés Cantor Goes West by Packy Anderson.

6. Weird encodings by Peter Campbell Smith.

7. Decrypted Goals by Roger Bell_West.

8. It’s all about the translation by Simon Green.

GitHub Repository Stats

1. Commits: 48,367 (+140)

2. Pull Requests: 13,741 (+43)

3. Contributors: 275

4. Fork: 349

5. Stars: 211 (+1)

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 - 364 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

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 #364.

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

Task 1: Alphabet Index Digit Sum

Submitted by: Mohammad Sajid Anwar

You are given a string $str consisting of lowercase English letters, and an integer $k.

Write a script to convert a lowercase string into numbers using alphabet positions (a=1 … z=26), concatenate them to form an integer, then compute the sum of its digits repeatedly $k times, returning the final value.

Example 1

Input: $str = "abc", $k = 1
Output: 6

Conversion: a = 1, b = 2, c = 3 -> 123
Digit sum: 1 + 2 + 3 = 6

Example 2

Input: $str = "az", $k = 2
Output: 9

Conversion: a = 1, z = 26 -> 126
1st sum: 1 + 2 + 6 = 9
2nd sum: 9

Example 3

Input: $str = "cat", $k = 1
Output: 6

Conversion: c = 3, a = 1, t = 20 -> 3120
Digit sum: 3 + 1 + 2 + 0 = 6

Example 4

Input: $str = "dog", $k = 2
Output: 8

Conversion: d = 4, o = 15, g = 7 -> 4157
1st sum: 4 + 1 + 5 + 7 = 17
2nd sum: 1 + 7 = 8

Example 5

Input: $str = "perl", $k = 3
Output: 6

Conversion: p = 16, e = 5, r = 18, l = 12 -> 1651812
1st sum: 1 + 6 + 5 + 1 + 8 + 1 + 2 = 24
2nd sum: 2+4 = 6
3rd sum: 6

Task 2: Valid Token Counter

Submitted by: Mohammad Sajid Anwar

You are given a sentence.

Write a script to split the given sentence into space-separated tokens and count how many are valid words. A token is valid if it contains no digits, has at most one hyphen surrounded by lowercase letters, and at most one punctuation mark (!, ., ,) appearing only at the end.

Example 1

Input: $str = "cat and dog"
Output: 3

Tokens: "cat", "and", "dog"

Example 2

Input: $str = "a-b c! d,e"
Output: 2

Tokens: "a-b", "c!", "d,e"
"a-b" -> valid (one hyphen between letters)
"c!"  -> valid (punctuation at end)
"d,e" -> invalid (punctuation not at end)

Example 3

Input: $str = "hello-world! this is fun"
Output: 4

Tokens: "hello-world!", "this", "is", "fun"
All satisfy the rules.

Example 4

Input: $str = "ab- cd-ef gh- ij!"
Output: 2

Tokens: "ab-", "cd-ef", "gh-", "ij!"
"ab-"   -> invalid (hyphen not surrounded by letters)
"cd-ef" -> valid
"gh-"   -> invalid
"ij!"   -> valid

Example 5

Input: $str = "wow! a-b-c nice."
Output: 2

Tokens: "wow!", "a-b-c", "nice."
"wow!"  -> valid
"a-b-c" -> invalid (more than one hyphen)
"nice." -> valid

Last date to submit the solution 23:59 (UK Time) Sunday 22nd March 2026.