diff --git a/2024/Day_16/README.md b/2024/Day_16/README.md index fc866f9..c3d0993 100644 --- a/2024/Day_16/README.md +++ b/2024/Day_16/README.md @@ -98,3 +98,57 @@ In this maze, the best paths cost **`11048`** points; following one such path wo Note that the path shown above includes one 90 degree turn as the very first move, rotating the Reindeer from facing East to facing North. Analyze your map carefully. **What is the lowest score a Reindeer could possibly get?** + +--- + +## --- Part Two --- + +Now that you know what the best paths look like, you can figure out the best spot to sit. + +Every non-wall tile (`S`, `.`, or `E`) is equipped with places to sit along the edges of the tile. While determining which of these tiles would be the best spot to sit depends on a whole bunch of factors (how comfortable the seats are, how far away the bathrooms are, whether there's a pillar blocking your view, etc.), the most important factor is **whether the tile is on one of the best paths through the maze**. If you sit somewhere else, you'd miss all the action! + +So, you'll need to determine which tiles are part of **any** best path through the maze, including the `S` and `E` tiles. + +In the first example, there are **`45`** tiles (marked `O`) that are part of at least one of the various best paths through the maze: + +``` +############### +#.......#....O# +#.#.###.#.###O# +#.....#.#...#O# +#.###.#####.#O# +#.#.#.......#O# +#.#.#####.###O# +#..OOOOOOOOO#O# +###O#O#####O#O# +#OOO#O....#O#O# +#O#O#O###.#O#O# +#OOOOO#...#O#O# +#O###.#.#.#O#O# +#O..#.....#OOO# +############### +``` + +In the second example, there are **`64`** tiles that are part of at least one of the best paths: + +``` +################# +#...#...#...#..O# +#.#.#.#.#.#.#.#O# +#.#.#.#...#...#O# +#.#.#.#.###.#.#O# +#OOO#.#.#.....#O# +#O#O#.#.#.#####O# +#O#O..#.#.#OOOOO# +#O#O#####.#O###O# +#O#O#..OOOOO#OOO# +#O#O###O#####O### +#O#O#OOO#..OOO#.# +#O#O#O#####O###.# +#O#O#OOOOOOO..#.# +#O#O#O#########.# +#O#OOO..........# +################# +``` + +Analyze your map further. **How many tiles are part of at least one of the best paths through the maze?**