yfangzhe
2020-12-20 18:35:07

Just finish part 2. Find that in those test and input file, rule 0 is always “0: 8 11”. As we know rule 8 is 42+, and rule 11 is 42+ 31+ (same number of 42s and 31s). So rule 0 is 42+ 31+ where the number of 42s should more than 31s.


hoshom
2020-12-20 19:20:54

I finally got a successful, thread-per-cell based version of day 11 part 1 working. It’s quite slow, but it works :smile: https://github.com/hashimmm/adventofcode/blob/master/2020/day11.rkt If the idea interests anyone enough to give it a look, comments/suggestions are welcome :slightly_smiling_face:


badkins
2020-12-21 02:11:59

Yikes. Day 20 was fun, and I’m glad I did Part 1 in such a way as to make Part 2 not overly hard, but it definitely took me longer than the 25.5 minutes for the day’s leader :)


badkins
2020-12-21 02:13:17

I’m curious about one aspect. I’ll ask in a thread to avoid spoilers.


me1890
2020-12-21 02:15:32

I am having a very hard time on today’s problem. I’m not done with part 2 yet, but i’ve been working on it for a while


badkins
2020-12-21 02:16:12

I’m curious about the approaches used to handle the various rotations and flip. My first thought was to leave the tiles alone, and simply use a different getter for each orientation. See lines 9–15 <https://github.com/lojic/LearningRacket/blob/master/advent-of-code–2020/day20.rkt|in my solution> . It made some things easy, but having to keep track of the orientation per tile so I could use the appropriate getter made other things harder. I’m a little too burned out on it to try the other approach. Probably just different tradeoffs re: convenience.


badkins
2020-12-21 02:16:45

I won’t tell you how long I spent on it - too embarrassing :)


badkins
2020-12-21 02:17:27

I think the person that submitted in 25.5 minutes must’ve had something very similar that could be tweaked.


me1890
2020-12-21 06:13:35

Today’s problem was much more doable and fun


jonathanhwchan
2020-12-21 06:23:48

:sparkles:ingredience:sparkles:


haskal
2020-12-21 06:40:09

yeah this was a big step down in difficulty tbh, but i took forever on part 2 due to a bug x___x


haskal
2020-12-21 06:40:55

so i ended up with places 109 and 1085 i nearly broke 100 again on part 1 though if i was just a little faster….


haskal
2020-12-21 06:41:15

solution in thread >>


haskal
2020-12-21 06:41:44

https://git.lain.faith/haskal/aoc2020/src/branch/aoc2020/21.rkt

i use the old friend maximum-bipartite-matching again


haskal
2020-12-21 06:47:22

“anyway so maximum-bipartite-matching is OP as [heck]” ~ hazel


me1890
2020-12-21 06:47:55

It seems very useful, but i haven’t used graph at all yet


me1890
2020-12-21 06:48:05

I solved today’s problem with mostly set operations