What kind of machine are you running this on? Because my implementation is essentially the same as yours but won't go below ca 40 ms

Grrrr.... lower right hand corner != upper left hand corner. Aka "why are all my answers off by 2?!"

I don't think that you need to go beyond about 200 iterations as the resulting pattern settles to a Steady State even through it drifts rightward 1 character per iteration. After this all this does is add a score of 1 per alive plant per iteration & so you can shortcut the calculation for 50,000,000,000

I got to use

window

, so that's always a good time. 🙂

If you want to punish yourself: Heres an oscillator whose cycle starts at 2 and ends at 4, and glides off to positive infinity.

initial state: ##.##..#

..... => .
....# => .
...#. => .
...## => .
..#.. => #
..#.# => .
..##. => .
..### => .
.#... => .
.#..# => .
.#.#. => .
.#.## => .
.##.. => .
.##.# => .
.###. => .
.#### => .
#.... => #
#...# => .
#..#. => .
#..## => .
#.#.. => .
#.#.# => .
#.##. => .
#.### => .
##... => .
##..# => .
##.#. => .
##.## => #
###.. => .
###.# => .
####. => .
##### => .

I tried to optimize my code in preparation from part two but of course as it turns out that still wasn't fast enough.

Okay, I have rendering for Minecart Madness part 1, but I think I'm going to sleep before I do their movements.

Nothing special today, it was easier than expected when I first saw the input 😒imple_smile:

I got only Part B wrong, but I have no idea why. Code from @andyb works fine with different result. So maybe I didn't understand the question correctly, although for their example input for part B my result is correct.

My day 13 is here: https://github.com/jorispz/aoc-2018/blob/master/src/commonMain/kotlin/P13.kt No interesting constructs that others haven't posted earlier, though I am quite pleased with

private val turns = sequenceOf(Turn.LEFT, Turn.STRAIGHT, Turn.RIGHT).infinite().iterator()

Today's timings also nothing surprising (first/best of 25 in ms): JVM

182/13

, JS

206/75

, native

1048/995

Instant regret

Day 14: Yet another win for Kotlin Sequences 🙂 Initial solution here: https://gitlab.com/abowes/adventofcode2018/blob/master/src/main/kotlin/jfactory/day14/ChocolateCharts.kt

You can't have the stoppingpoint as an

Int

, what if it starts with

'0'

like one of the testcases?

I'm kind of stuck on the second part, all the examples work, but apparently my answer is wrong 😞

Giving up for today, still working on part 1. My code handles the examples correctly, but is terribly slow on the real input, a combination of doing too much work with way too much memory. More tomorrow, though I might do day 16 first

I feel the same. I write all these up, but since I disable comments on my blog who the heck knows if anybody even sees it.

So there's that. Maybe I don't understand how reading order works?

Oh why Slack, a platform for professionals has no syntax highlighting, and Discord, a platform for gamers, has highlighting for all languages. 😕

@Rostyslav Isn't it a little confusing that you assigned numbers to opcodes in your executing function but they are not the real opcode numbers? I couldn't figure out how did you know the opcode numbers straight away to write that function. 😄

I might give up on day 15 unless we get more test cases that are blessed as correct by Saint Nicholas himself. Right now I'm trying to debug based on comments on reddit, but some of them directly contradict each other 😖

You people need to learn how to write your lists of functions more compactly 😉

Found a nice usage of

generateSequence

for second part of Day 15:

return generateSequence(4) { it + 1 }
    .map { elfAttack -> fight(inputs, elfAttack) }
    .first { result -> result.beings.none { it.kind == BeingKind.ELF && !it.alive } }
    .score

I often want function that generates an infinite list of incrementing numbers, but I keep forgetting about

generateSequence

!

Heh that reminds me: what does the program we interpreted today actually do?

Part 1 is fine. part 2 gives wrong answer. I've had no time to work on this between moving, chores and errands associated with it, and debilitating headaches I get sometimes. I found all of the operations that seem to be singletons by removing ids from contention, but it yields the wrong answer. So either I'm doing that wrong and have the wrong instructions or I'm executing one wrong. Blah.

I'm pretty sure my Day 15 isn't working because of a) My pathfinding algorithm is the wrong choice (A*) and I should have done a more straight forward DFS, b) Constant headaches keeping me from focusing on details, c) Lack of time. Going to write up D16 and then try again later. I feel like I'm close, finding paths better is possibly it.

Finished and generated a video: https://streamable.com/i29ew

I think it's time to call it quits with AoC for now. At least on a "do it every day" basis. Puzzles have gotten too hard to 'casually' solve them, plus I'm way behind my Master's coursework (which I might bail on anyway). It was fun while the drive lasted, I'll definitely tackle the problems when I have free time again. 🙂

Maybe there's a better way, I hate the literal code duplication there.