Mercurial > repos > other > adventofcode2023
view day16.txt @ 24:19481b061461
Implement tilting and cycling for Day 14 part 2
Lots of false starts trying to iterate. Eventually looked for
"back in same position" to spot a loop. Then took longer to
spot that "same position" isn't necessarily "start position"
and loop can be offset!
| author | IBBoard <dev@ibboard.co.uk> |
|---|---|
| date | Sat, 16 Dec 2023 20:39:02 +0000 |
| parents | ad73a2ff3d06 |
| children |
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--- Day 16: The Floor Will Be Lava --- A laser/mirror problem - "/" and "\" are mirrors that reflect 90°. "-" and "|" are splitters - transparent in the same orientation, but TWO beams go at 90° if hit against the flat edge. "." is empty space. The laser starts in the top-right. For an example map: .|...\.... |.-.\..... .....|-... ........|. .......... .........\ ..../.\\.. .-.-/..|.. .|....-|.\ ..//.|.... The laser goes: >|<<<\.... |v-.\^.... .v...|->>> .v...v^.|. .v...v^... .v...v^..\ .v../2\\.. <->-/vv|.. .|<<<2-|.\ .v//.|.v.. Every space that the laser goes through is "energised", which gives: ######.... .#...#.... .#...##### .#...##... .#...##... .#...##... .#..####.. ########.. .#######.. .#...#.#.. The count of energised spaces is 46.