The occasional scrivener

This blog post is a work in progress

Project website: Advent of Code 2019.

Previous years: 2015, 2016, 2017, 2018.

I use Perl for all the solutions.

Most assume the input data is in a file called input.txt in the same directory as the file.

A note on scoring

I score my problems to mark where I’ve finished a solution myself or given up and looked for hints. A score of 2 means I solved both the daily problems myself, a score of 1 means I looked up a hint for one of the problems, and a zero score means I didn’t solve any of the problems myself.

My goals for this year (in descending order of priority):

• get 38 stars or more (75%)
• solve all problems within 24 hours of release

Link to Github repo.

Day 1 - Day 2 - Day 3 - Day 4 - Day 5 - Day 6 - Day 7

Day 1 - The Tyranny of the Rocket Equation

Day 1 - complete solution

A nice and simple problem to kick off this year.

Score: 2

Day 2 - 1202 Program Alarm

Day 2 - complete solution

An earlier appearance of register rodeo than expected! I think we’ll see more of this going forward.

Score: 2

Day 3 - Crossed Wires

Day 3 - complete solution

This took longer than it had to. I messed up adding the paths, and only managed to get the correct answer to part 1 by chance. Once I plotted the example data I could correct the code, then add the logic for part 2.

I’m not entirely happy with the duplicated direction subroutines. Some people have used complex numbers to simplify this but that would require a separate Perl module to implement.

Score: 2.

Day 4 - Secure Container

Day 4 - complete solution

I blanked on this one and dreaded combinatorics. Turns out brute force is eminently doable. Credits to /u/andreyrmg in the daily solutions thread, and A_D and sim642 in the IRC channels for help in inspiration.

I still think my solution is my own though (and pretty Perlish), so full score today.

Score: 2.

Day 5 - Sunny with a Chance of Asteroids

Day 5 - complete solution

After struggling with the convoluted problem description I was pleasantly surprised to find my code ran flawlessly first try. I still have some niggling issues with the test data, and need to clear that up before the inevitable next intcode problem.

Score: 2.

Day 6 - Universal Orbit Map

Day 6 - complete solution

I bailed on this one and sought inspiration in the daily solutions subreddit. Credit in source!

Score: 0.

Day 7 - Amplification Circuit

Day 7 - part 1 Day 7 - part 2

A tough, but fun one. There were a lot of subtleties in the second part, and I got some pointers from the subreddit.

I got the chance to clean up my intcode implementation, and learned a new facet of Perl.

Score: 2.

This is an excellent and entertaining view of the war between Republicans and their opponents in the years between 1870 and World War 1. It reminds the reader of the virulent anti-Semitism of French discourse at the time.

As an example, Lt. Col. Henry was instrumental in framing Alfred Dreyfus. He literally forged evidence to “prove” Dreyfus’ guilt. When he was arrested and committed suicide in prison, he was hailed a hero. A subscription was started to finance a lawsuit bought by his wife against Joseph Reinach for libel. A journalist collected the testimonials in a book, and the statements from that book, excerpted in a footnote, are among the most chilling in the entire book:

“From an antisemitic merchant in Boulogne-sur-Mer who hopes that the Hebes are blown away, above all Joseph Reinach, that unspeakable son-in-law and nephew of the Panama swindler one of whose victims I am.” “From a cook who would rejoice in roasting Yids in her oven.” “Long live Christ! Love live France! Long live the Army! A curate from a little very antisemitic village.” “One franc to pay for the cord that hangs Reinach.” “Joan of Arc, help us banish the new English.” “Two francs to buy a round of drinks for the troopers who will shoot Dreyfus, Reinach, and all the traitors.” A resident of Baccarat wanted “all the kikes” in the region—men, women, and children—thrown into the immense ovens of the famous crystal factory. Another contributor longed, prophetically, for the day that a “liberating boot” would appear over the horizon.

In these days where the ideas of sange et terre are making a resurgance, it’s instructive to look back on a time where the Right expressed itself in its true voice.

Rom: marmor och människor av Hans Furuhagen — The Storm Before the Storm - the Beginning of the End of the Roman Republic by Mike Duncan — Hos etruskerna av Alf Henrikson

Furuhagens bok är en lättläst krönika om den eviga staden, med mycket focus på dom människor som såg till att staden ser ut som den gör idag, samt själva byggnaderna och gatorna.

Med avstamp i Augustus första dagar blir det med tiden en hel del påvar, men även konstnärer. Det nordiska inslagen är naturligtvis väl täckta, med de två olika kvinnorna Birgitta och Christina som kontraster i tid och rum.

Duncan’s book has more details of the ground covered in his podcast, and I find the written word congenial in following along with the twists and turns of the violence of the late Republic.

Antingen älskar man Henrikson eller så tycker man han är mossigare än antiken han skiver om. Jag tillhör de förstnämnda.

Ett smakprov (s. 34):

[Etruskerna] utbildade ett legitemerat prästerskap med särskilda haruspices med långvarig skolning i framför all leverns topografi. Levern är ju ett stort organ och kan även hos friska djur förete stora individuella olikheter, upplyser länsveterinären Garmer på särskild förfrågan; det bör alltså ha varit möjligt för den troende att ur dess uppsyn ärligt utläsa både ditt och datt. […] På levern liksom på himlen finns en gynnsam pars familiaris och en motig pars hostilis. Gränslinjen dem emellan kallas fissum och en eventuell upphöjning på leverytan heter caput iocinoris, om det kan intressera någon nutida levande människa.

Björn Bergs illustrationer förstärker den mysiga mossiga stämningen.

Oct 2018 | Oct 2017 | Oct 2016 | Oct 2015 | Oct 2014 | Oct 2013 | Oct 2012 | Oct 2011 | Oct 2010 | Oct 2009 | Oct 2008

I caught the movie adaptation of this book on a flight, and wanted to get some more background. Honestly, the movie does a good job of summarizing the contents, but also adds some humanizing touches such as the visit to the ground zero of the housing market: Florida. Both are recommended.

Sep 2018 | Sep 2017 | Sep 2016 | Sep 2015 | Sep 2014 | Sep 2013 | Sep 2012 | Sep 2011 | Sep 2010 | Sep 2009 | Sep 2008 |

Aug 2018 | Aug 2017 | Aug 2016 | Aug 2015 | Aug 2014 | Aug 2013 | Aug 2012 | Aug 2011 | Aug 2010 | Aug 2009

HN&&LO is a web page that scrapes the APIs of Hacker News and Lobste.rs and collates those entries that share a URL.

This lets you easily follow the discussion on both sites for these links.

I wrote this tool because I’m much more active on Lobste.rs than on HN, but I would like to keep “tabs” on both sites. I’m especially interested in how the information is disseminated between the sites.

“Slow webapps”

I’ve long liked to grab stuff via a web API, stuff it into a DB, and output a web page based on the data. This project was a first attempt to use a templating engine in Perl, and I’m ashamed to say I’ve taken so long to understand the greatness of this approach.

The data updates hourly, there’s rarely more than a couple of new entries on Lobste.rs per hour.

In fact, this can illustrate the difference in scale between the two sites.

Time period: 5 Jul 2019 11:19 to 8 Aug 2019 23:59 (both times in UTC).

• Number of submissions with URLS on Hacker News: 26,974
• Number of submissions on Lobste.rs: 899

Average number of submissions per hour: 33 for HN, 1 for Lobste.rs.

Once updated, a static web page is generated. This keeps overhead low.

Differences between Hacker News and Lobste.rs

Coincidentally, while I was writing this post, an article was published in the New Yorker about the moderators (all two of them) of Hacker News. This sparked a discussion on HN (obviously) but also on Lobster.rs (see both linked here).

To me, what makes Lobste.rs better is that it’s much smaller (one can easily catch up with a day’s worth of comments), the editing tools are more sophisticated, and the tag system allows one to determine whether a post is interesting or not. HN is much harder to grasp.

I think the tendencies noted in the article are common to both sites - male, youngish software developers with a rationalist bent. But I think Lobste.rs is a bit more self-aware of this fact (or rather, critiques are more visible there). In some ways, Lobste.rs, being a reaction to HN, defines itself culturally both for and against the bigger site.

Source and TODO

If you’re interested in pedestrian Perl code, source is here.

TODO list is here

Jul 2018 | Jul 2017 | Jul 2016 | Jul 2015 | Jul 2014 | Jul 2013 | Jul 2012 | Jul 2011 | Jul 2010 | Jul 2009

Mandy Barker - Sea of Artifacts

An earnest exploration of plastic in seas and waterways. For some reason this exhibit was in a room even more dimly lit than usual at Fotografiska - and that’s saying something. Sadly nothing that’s not been said or done many times before.

Scarlett Hooft Graafland - Vanishing Traces

This grew on me. Staged images in different environments with surreal components (yet of course it’s all “analog” and there’s no manipulation). Impressive for the visuals and conceptions alone.

Vincent Peters - Light Within

Peters photographs our modern Hollywood idols like they where 1940s Hollywood idols.

James Nachtwey - Memoria

A visual onslaught of images from famines, wars, catastrophes and field hospitals. Almost unbearable in its intensity. I became numb after just a few walls. It depresses me that future epigones will have no shortage of similar subjects, all without having to travel that far.