Mercurial > repos > other > adventofcode2023
view day21.txt @ 30:6de4f4d5404d
Implement Day 21 "possible spaces in a maze"
Part 2 needs something like "find the repeats
and lowest common multiple" that I'm not bothering with
| author | IBBoard <dev@ibboard.co.uk> |
|---|---|
| date | Wed, 03 Jan 2024 12:01:18 +0000 |
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--- Day 21: Step Counter --- You are in a maze. `S` is your starting position. `.` is open. `#` is blocked. How many spaces can you get to in N steps? e.g. for this map: ........... .....###.#. .###.##..#. ..#.#...#.. ....#.#.... .##..S####. .##..#...#. .......##.. .##.#.####. .##..##.##. ........... You can be in any of 16 spaces after 6 steps. ........... .....###.#. .###.##.O#. .O#O#O.O#.. O.O.#.#.O.. .##O.O####. .##.O#O..#. .O.O.O.##.. .##.#.####. .##O.##.##. ........... How many spaces are there after 64 steps? -- Part 2 -- The map tiles infinitely and you need to take 26501365 steps. How many spaces can you reach now? And does anyone care?