Should I feel silly? I wondered how many "failing" items actually go to the real solver and the answer is 0. My challenge input has no "close calls", and pre-solver pruning check of grid area being enough for all required tiles solves the challenge in milliseconds instead of around ten minutes.

I still need to write a visualizer to better understand how it really works inside, it's that clever. And memory hungry, at its peak the solver used over 30GiB of active memory running a few in parallel. (3/3)

After a bit of research on coverage problems I ended up watching Donald Knuth explaining his Dancing Links algorithm for an hour and a half. Bit more reading and writing later I had a working solver and finally a solution. (2/3)

Advent of Code 2025 had only 12 puzzles, but the last one taught me something new. The "sample" data was solved quickly with BFS, but the real event input would have taken millions of years. (1/3)

Eräästä OneDrivestä näyttää puuttuvan yksi #Mikrobitti. Mikähän numero se on ollut?

FYI "Olympiakomitea on pyytänyt kaikkia jäsenjärjestöjään tiedottamaan jäsenilleen, että urheilun oikeusturvalautakunnan sähköposti on kaapattu. Urheilun oikeusturvalautakunnan nimissä on lähetetty kalasteluviestejä, joissa linkki johonkin asiakirjaan. Älkää missään nimessä avatko sitä!"

Sinällään jännää, miten hankalaa on ollut oppia suomennoksen sanat tuttuihin biiseihin joita on laulanut viroksi. Osansa on toki sillä, etteivät suomennoksen sanapainot istu aina luontevasti, koska sävellys on tehty todella hyvin viron sanapainoja hyödyntäen.

Vihdin kirkossa su 2.3.2025 klo 18. Vapaa pääsy.

Laskiaissunnuntaina illalla on mahdollisuus kokea Urmas Sisaskin mahtava Eestiläinen Messu (suomeksi laulettuna) ja Arvo Pärtin urkumusiikkia.

Light blue Selle SMP TRK saddle with green ribbon saying it's "E-bike ready"

I didn't know that ebikes have different reqs for saddles. I hope this is also ready for my indoor trainer...

MathML tuki riittäisi suurimpaan osaan tarpeista. Monet wikimoottoritkin tukevat sitä.

The Earth's elliptical orbit causes interesting phenomena.

Tomorrow, Dec 16th, will be this year's earliest sunset. The night is at its longest on Dec 21st, and the latest sunrise is on December 26th. The Earth's maximum orbital speed is at perihelion on Jan 4th, 2025, then to slow down again.

Traditional heatwave surrounds the #apidays Helsinki. This year has again an interesting spread of topics across few tracks.

Local ski slopes in the evening.

Two good things of the nippy weather (-20°C) is that the slopes are in excellent condition and they're not overcrowded.

Okay, had to give up on brute-forcing it. It was still only 1/4 done, so it would have taken ~34hrs.

Polyglot Notebook version of DFS with contracted edges took 12s, and AOT compiled C# native binary took 7s. Of course it used a dynamic programming cache to speed things up with a "small" factor.

ps. I did this in VScode Polyglot Notebook, and the visualization updates every 100k steps at around 2fps. Cyan is current status, green is longest known route thus far.

Visualization of depth-first search for a longest path problem.

This year I've been leisurely doing the Advent of Code challenges. They've been reasonable head-scratchers at times to figure out which non-brute-force algorithm would give a result before the heat-death of the universe.

Today's Part-2 is NP hard and you can basically just optimize the data struct.