Add 2023 solutions

README.md

@@ -98,3 +98,53 @@ written in Python.
 - Day 7: 20:15
 - Day 8: 18:35
 - Day 9:
+
+# 2022
+
+
+# 2023
+
+- Day 1: 40:00 (I don't know what I am doing.)
+- Day 2: 14:15 (Okay, but far way from leaderboard.)
+- Day 3: 1st 20:00, 2nd 70:00... (I had a logic error that took me a while to
+  find.)
+- Day 4: 1st 9:06, 2nd 22:31; it wasn't hard but I didn't think quick enough :/
+- Day 5: 1st 25:00, 2nd 1:55:00; Required patience and accuracy
+- Day 6: 13:54; I was slow because I thought it is much harder?
+- Day 7: 75:00; leaderboard 16:00... that was just bad; no excuse
+- Day 8: 25:00; I was doing pretty decent here.
+- Day 9: 57:00; my input parse function did not consider negative values...
+- Day 10: 180:00; this one was hard for me.
+- Day 11: 68:00; okay but not elegant and way too slow ofc; x-ray solution
+  would have been neat
+- Day 12: 52:00 and 22:00 for leaderboard; had the right idea and I am good at
+  this type of problem
+- Day 13: 90:00; pretty straightforward  but way too slow
+- Day 14: 5:55 for first and then 48:00; straightforward but slow, ofc
+- Day 15: 4:30 and 31:20; more reading comprehension than programming
+- Day 16: 00:27:30 745; best placement so far, of course still horribly slow
+- Day 17: a couple of hours; I realized that I need A* after a while; reused
+  implementation from Project Euler but improved with heapq which was super fun
+- Day 18: a couple of hours; I realized that I need shoelace algo for part two
+  but didn't realize that I have to compute the outer edges for a while and
+  after I did, I still got clockwise/counter-clockwise issues. They could have
+  made it meaner by using different clock directions for example and input.
+- Day 19: This one was pretty straightforward and required the interval
+  technique we applied earlier.
+- Day 20: Part 2 was tough. I had the right idea of printing out the periods of
+  the input conjunction gate pretty early, but then messed up the
+  implementation and thought it wasn't gonna work. Spent a half day thinking up
+  something else before returning to the idea and it worked flawlessly.
+- Day 21: Part 1 was straightforward, but part 2 maybe the hardest problem this
+  year.
+- Day 22: Not too hard, but definitely way too slow for leaderboard.
+- Day 23: I found this fun because it required some creativity for part 2. Slow
+  af, of course.
+- Day 24: Solve problem with sympy. I first used numpy to solve part 1 and it
+  was much faster than using sympy, but I lost that solution when switching to
+  sympy. Takes about three minutes to run for part 1 and then part 2 is under a
+  second.
+- Day 25: I cheeky solved this by plotting the graph and manually removing the
+  nodes. I should probably try to write an algorith that does that, but meh.
+  Manually plotting requires matplotlib and networkx packages.
+