Day 10: Pipe Maze

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  • cacheson@kbin.social
    2·
    1 year ago

    Nim

    I got a late start on part 1, and then had to sleep on part 2. Just finished everything up with a little time to spare before day 11.

    Part 2 probably would have been easier if I knew more about image processing, but I managed:

    • Made a copy of the grid and filled it with . tiles
    • Copied all of the path tiles that I had calculated in part 1
    • Flood-filled all the . tiles that are connected to the outside edges of the grid with O tiles
    • Walked along the path, looking for an adjacent O tile at each step. Stopped when one was found, and recorded whether it was to the left or right of the path.
    • Walked the path again, flood-filling any adjacent inside . tiles with I, and counted them

    Code: