I think that 2020 contains sone of my favorite visualizations, and this- the first of the year- is definitely among them.

In 2020, our main character finds herself taking a trip. We depart the north pole, and on day 11, finally make our way via air flight to our tropical destination.

The puzzle is to model a finite automata until it reaches its stable state, and we prove we’ve done so by reporting the number of “occupied” seats. As is common, part 2 complicates the rules.


Somewhat unusually, the visualization of part 1 is a lot more interesting than part 2. We get a double header today, though, and we get to see both.

Part 1

Day 11 Part 1 Visualization

Part 2

Day 11 Part 2 Visualization

New Features

From reviewing git logs, I don’t think there are any new features of note in Day 11. I was producing visualizations in 2019, and re-used that code.