Perl Weekly Challenge

HEADLINES

Today is the first Monday of the July 2020 and you guessed it correctly. It is time to announce the Champion of the Month. With great pleasure, we announce the Champion of last month, Mark Anderson, currently ranked #027 with score of 122. He joined the Team PWC in the Week #018. As of today, he has contributed Perl (19) and Raku (42).

After a long gap, we have Perl and Raku reviews together in one week. I would like to thank Colin Crain and Laurent Rosenfeld for the quality work they have done. We are still looking for volunteer to help with Raku. I don’t expect one person to do it all. Even if you do one or two that would be a great help to clear the backlog,

A gentle reminder about Early Bird Club, if you want to check out the weekly challenge before Monday for whatever reason then please join the club. By joining the club, you get to review the task before it goes public. Also you get extra time to work on your solutions. Joining is very easy, just drop me a line at perlweeklychallenge@yahoo.com and that’s it.

I don’t know why but I keep adding more work for myself every now and then. As you must have noticed, I am currently hooked into Live Coding fun. I find it hard to find the time where I can be left alone to do the video. Mostly it is late night, not sure if you noticed the system time in the video. I hate doing late night but I am left with no choice. Monday to Friday daytime belongs to the regular day job. Evening time is for Family. So you see, either I do it late night or do it during weekends. But most weekends, I am busy with the admin work of Perl Weekly Challenge. Anyway, here is my videos for the two tasks. Please don’t forget to subscribe my YouTube Channel if you like the videos,

a) Number Combinations

b) Letter Phone

Also have a look at Richard Park‘s video, the source of inspiration for me,

Last but not the least, I would like to thank each and every member for their support and encouragement.

RECAP

Quick recap of the “Perl Weekly Challenge - 067” by Mohammad S Anwar.

PERL REVIEW

Please checkout Perl solutions review of the “Perl Weekly Challenge - 066” by Colin Crain.

If you missed any past reviews then please checkout the collection.

RAKU REVIEW

Please checkout Raku solutions review of the “Perl Weekly Challenge - 058” by Laurent Rosenfeld.

If you missed any past reviews then please checkout 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 give it a try to an excellent tool EZPWC created by respected member Saif Ahmed of Team PWC.

GUESTS

Leo Manfredi shared solution to Task #1 in Python.

Richard Park shared solutions to Task #1 and Task #2 in APL.

Ulrich Rieke shared solution to Task #2 in C++.

Walt Mankowski shared solutions to Task #1 and Task #2 in Python.

Wanderdoc shared solutions to Task #1 and Task #2 in R.

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

TASK #1 › Zero Matrix

Submitted by: Mohammad S Anwar

You are given a matrix of size M x N having only 0s and 1s.

Write a script to set the entire row and column to 0 if an element is 0.

Example 1

Input: [1, 0, 1]
       [1, 1, 1]
       [1, 1, 1]

Output: [0, 0, 0]
        [1, 0, 1]
        [1, 0, 1]

Example 2

Input: [1, 0, 1]
       [1, 1, 1]
       [1, 0, 1]

Output: [0, 0, 0]
        [1, 0, 1]
        [0, 0, 0]

TASK #2 › Reorder List

Submitted by: Mohammad S Anwar

You are given a singly linked list $L as below:

L0 →  L1 →  … →  Ln-1 →  Ln

Write a script to reorder list as below:

L0 →  Ln →  L1 →  Ln-1 →  L2 →  Ln-2 →

You are ONLY allowed to do this in-place without altering the nodes’ values.

Example

Input:  1 →  2 →  3 →  4
Output: 1 →  4 →  2 →  3

Last date to submit the solution 23:59 (UK Time) Sunday 12th July 2020.