day_8

Day 8

Things starting to get a bit weird now...

Some nice stuff with calculating gradients and euclidian distance that was fun though.

Part 1

1. Iterate through grid storing all points associated with a char in a hash map.
2. Perform a nested loop through each char's associated points calculating the distance between the current location (a) and all other locations in the vector (b).
3. With the distance between locations a and b move away from a by this distance and away from b by the same distance. These locations are the antinodes.

Part 2

1. Using the same approach as Part 1, except now continue moving away from points a and b until the point becomes invalid, e.g., outside of the grid.