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--- Day 22: Reactor Reboot ---
Operating at these extreme ocean depths has overloaded the submarine's reactor; it needs to be
rebooted.
The reactor core is made up of a large 3-dimensional grid made up entirely of cubes, one cube per
integer 3-dimensional coordinate (x,y,z). Each cube can be either [1m[97mon[0m or [1m[97moff[0m; at the start of the
reboot process, they are all [1m[97moff[0m. (Could it be an old model of a reactor you've seen before?)
To reboot the reactor, you just need to set all of the cubes to either [1m[97mon[0m or [1m[97moff[0m by following a list
of [1m[97mreboot steps[0m (your puzzle input). Each step specifies a cuboid (the set of all cubes that have
coordinates which fall within ranges for x, y, and z) and whether to turn all of the cubes in that
cuboid [1m[97mon[0m or [1m[97moff[0m.
For example, given these reboot steps:
on x=10..12,y=10..12,z=10..12
on x=11..13,y=11..13,z=11..13
off x=9..11,y=9..11,z=9..11
on x=10..10,y=10..10,z=10..10
The first step (on x=10..12,y=10..12,z=10..12) turns [1m[97mon[0m a 3x3x3 cuboid consisting of 27 cubes:
- 10,10,10
- 10,10,11
- 10,10,12
- 10,11,10
- 10,11,11
- 10,11,12
- 10,12,10
- 10,12,11
- 10,12,12
- 11,10,10
- 11,10,11
- 11,10,12
- 11,11,10
- 11,11,11
- 11,11,12
- 11,12,10
- 11,12,11
- 11,12,12
- 12,10,10
- 12,10,11
- 12,10,12
- 12,11,10
- 12,11,11
- 12,11,12
- 12,12,10
- 12,12,11
- 12,12,12
The second step (on x=11..13,y=11..13,z=11..13) turns [1m[97mon[0m a 3x3x3 cuboid that overlaps with the
first. As a result, only 19 additional cubes turn on; the rest are already on from the previous
step:
- 11,11,13
- 11,12,13
- 11,13,11
- 11,13,12
- 11,13,13
- 12,11,13
- 12,12,13
- 12,13,11
- 12,13,12
- 12,13,13
- 13,11,11
- 13,11,12
- 13,11,13
- 13,12,11
- 13,12,12
- 13,12,13
- 13,13,11
- 13,13,12
- 13,13,13
The third step (off x=9..11,y=9..11,z=9..11) turns [1m[97moff[0m a 3x3x3 cuboid that overlaps partially with
some cubes that are on, ultimately turning off 8 cubes:
- 10,10,10
- 10,10,11
- 10,11,10
- 10,11,11
- 11,10,10
- 11,10,11
- 11,11,10
- 11,11,11
The final step (on x=10..10,y=10..10,z=10..10) turns [1m[97mon[0m a single cube, 10,10,10. After this last
step, [1m[97m39[0m cubes are [1m[97mon[0m.
The initialization procedure only uses cubes that have x, y, and z positions of at least -50 and at
most 50. For now, ignore cubes outside this region.
Here is a larger example:
on x=-20..26,y=-36..17,z=-47..7
on x=-20..33,y=-21..23,z=-26..28
on x=-22..28,y=-29..23,z=-38..16
on x=-46..7,y=-6..46,z=-50..-1
on x=-49..1,y=-3..46,z=-24..28
on x=2..47,y=-22..22,z=-23..27
on x=-27..23,y=-28..26,z=-21..29
on x=-39..5,y=-6..47,z=-3..44
on x=-30..21,y=-8..43,z=-13..34
on x=-22..26,y=-27..20,z=-29..19
off x=-48..-32,y=26..41,z=-47..-37
on x=-12..35,y=6..50,z=-50..-2
off x=-48..-32,y=-32..-16,z=-15..-5
on x=-18..26,y=-33..15,z=-7..46
off x=-40..-22,y=-38..-28,z=23..41
on x=-16..35,y=-41..10,z=-47..6
off x=-32..-23,y=11..30,z=-14..3
on x=-49..-5,y=-3..45,z=-29..18
off x=18..30,y=-20..-8,z=-3..13
on x=-41..9,y=-7..43,z=-33..15
on x=-54112..-39298,y=-85059..-49293,z=-27449..7877
on x=967..23432,y=45373..81175,z=27513..53682
The last two steps are fully outside the initialization procedure area; all other steps are fully
within it. After executing these steps in the initialization procedure region, [1m[97m590784[0m cubes are
[1m[97mon[0m.
Execute the reboot steps. Afterward, considering only cubes in the region
x=-50..50,y=-50..50,z=-50..50, [1m[97mhow many cubes are on?[0m
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