const day22a = @import("day22a.zig");
const day22b = @import("day22b.zig");

    _ = try day22a.first();
    _ = try day22b.second();

const days = 21;

const days = 22;

## Day 20
I keep the lit items in a `std.AutoHashMap`, but generally the picture grid is
just an array of coordinates.

## Day 22

The first part is fast, as we only have to check the items in `-50..50` range.
The second part is much harder: We use coordinate compression: Each cube
switches on and off a range of coordinates, but we do not check them one-by-one,
just keeep track of the start and end of each range. This makes this solution
much faster.
TODO: C++ version takes 220ms, but the zig one is 9s. Why?