This December I participated in Advent of Code.

So. Looking back. Days 1-10 were fun, because it was fun to code again. Day 16 (1 point for walking forwards, 1000 to turn) was fun, after the fact, because I found an elegant way (with a nice diagram) to represent the labyrinth as a graph, and finally just implemented Dijkstra fully. Day 17 (build a small programming language) was very satisfying to solve, even if it involved a lot of paper. For day 19 (towels) I had to learn memoization. (I never learned this before?) Day 20 (a labyrinth that turns out just to be one long path, and it’s possible to walk through walls) it was an epiphany, that (part 1 of route) + (part 2 of route) – (discarded part in the middle) + (shortcut) was a way to solve the puzzle. Day 24 (a lot of gates) required some paperwork.

This is my attempt to fill out the complete personal times for me. I’m a little sad, that it simply says “more than 24 hours” officially.

Part 1 of days 17, 22 and 23 must have been easy, I spent minutes getting them right (just 2 or 7 or 8 days late). As I remember it, day 25 didn’t take a long time either, but I wanted to be well rested before I attempted it, so, happy surprise.

      --------Part 1--------   --------Part 2--------
Day       Time   Rank  Score       Time   Rank  Score
 25 8:03:01     22113      0 8:03:02     14148      0
 24 7:10:58     23368      0 8:11:00     15862      0
 23 7:20:30     23812      0 8:10:15     21472      0
 22 8:17:59     25204      0 8:20:00     21799      0
 21 9:10:07     19594      0 9:17:22     16355      0
 20 5:05:00     24815      0 6:02:28     21577      0
 19 4:06:00     28005      0 4:08:12     25333      0
 18 4:11:11     27991      0 4:11:49     27338      0
 17 2:09:34     28700      0 3:08:04     20591      0
 16 2:06:05     24090      0 3:08:50     25303      0
 15   01:19:07   5843      0   07:18:20   8861      0
 14   01:28:12   7258      0   02:13:42   6000      0
 13   03:04:50  11545      0   03:08:52   7714      0
 12   03:55:52  14298      0   04:04:26   7259      0
 11   00:24:58   6479      0   01:09:10   5330      0
 10   00:44:34   6515      0   00:48:19   6013      0
  9   01:26:25   9059      0   02:59:32   8039      0
  8   01:53:25  10087      0   02:04:40   9294      0
  7   17:55:39  47349      0   18:02:03  44377      0
  6   00:45:55   8375      0   02:18:28   8078      0
  5   13:07:46  55110      0   13:13:45  44839      0
  4   01:51:36  15622      0   02:06:52  13570      0
  3   16:51:27  91593      0   17:04:46  80436      0
  2   12:11:26  78108      0   13:30:49  60978      0
  1   17:12:43  92846      0   17:24:33  87414      0

This is, for completeness, based on these timestamps:

-rw-rw-r-- 1 slimbook slimbook      6773 Dec 19 14:50 d16c.php
-rw-rw-r-- 1 slimbook slimbook      4921 Dec 19 15:34 d17a.php
-rw-rw-r-- 1 slimbook slimbook     93787 Dec 20 14:04 day17b.ods
-rw-rw-r-- 1 slimbook slimbook      6166 Dec 22 17:11 d18a.php
-rw-rw-r-- 1 slimbook slimbook      6679 Dec 22 17:49 d18b.php
-rw-rw-r-- 1 slimbook slimbook      2092 Dec 23 08:43 d19a.php not right!!!
                                                12:00 ?
-rw-rw-r-- 1 slimbook slimbook      1075 Dec 23 16:12 d19b.php
-rw-rw-r-- 1 slimbook slimbook      4482 Dec 25 11:00 d20b.php
-rw-rw-r-- 1 slimbook slimbook      4393 Dec 26 08:28 d20c.php
-rw-rw-r-- 1 slimbook slimbook      9763 Dec 30 16:07 d21c.php
-rw-rw-r-- 1 slimbook slimbook     10164 Dec 30 23:22 d21e.php
-rw-rw-r-- 1 slimbook slimbook      1371 Dec 30 23:59 d22a.php
-rw-rw-r-- 1 slimbook slimbook      1951 Dec 31 02:00 d22b.php
-rw-rw-r-- 1 slimbook slimbook      1645 Dec 31 02:30 d23a.php
-rw-rw-r-- 1 slimbook slimbook       783 Dec 31 16:15 d23tmp.txt

-rw-rw-r-- 1 slimbook slimbook      1878 Dec 31 16:58 d24a.php
-rw-rw-r-- 1 slimbook slimbook      7940 Jan  1 17:00 d24mermaid3.txt
-rw-rw-r-- 1 slimbook slimbook      1217 Jan  2 09:01 d25a.php
                                                09:02