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--- Day 14: Parabolic Reflector Dish ---

   You reach the place where all of the mirrors were pointing: a massive
   [16]parabolic reflector dish attached to the side of another large
   mountain.

   The dish is made up of many small mirrors, but while the mirrors
   themselves are roughly in the shape of a parabolic reflector dish, each
   individual mirror seems to be pointing in slightly the wrong direction. If
   the dish is meant to focus light, all it's doing right now is sending it
   in a vague direction.

   This system must be what provides the energy for the lava! If you focus
   the reflector dish, maybe you can go where it's pointing and use the light
   to fix the lava production.

   Upon closer inspection, the individual mirrors each appear to be connected
   via an elaborate system of ropes and pulleys to a large metal platform
   below the dish. The platform is covered in large rocks of various shapes.
   Depending on their position, the weight of the rocks deforms the platform,
   and the shape of the platform controls which ropes move and ultimately the
   focus of the dish.

   In short: if you move the rocks, you can focus the dish. The platform even
   has a control panel on the side that lets you tilt it in one of four
   directions! The rounded rocks (O) will roll when the platform is tilted,
   while the cube-shaped rocks (#) will stay in place. You note the positions
   of all of the empty spaces (.) and rocks (your puzzle input). For example:

 O....#....
 O.OO#....#
 .....##...
 OO.#O....O
 .O.....O#.
 O.#..O.#.#
 ..O..#O..O
 .......O..
 #....###..
 #OO..#....

   Start by tilting the lever so all of the rocks will slide north as far as
   they will go:

 OOOO.#.O..
 OO..#....#
 OO..O##..O
 O..#.OO...
 ........#.
 ..#....#.#
 ..O..#.O.O
 ..O.......
 #....###..
 #....#....

   You notice that the support beams along the north side of the platform are
   damaged; to ensure the platform doesn't collapse, you should calculate the
   total load on the north support beams.

   The amount of load caused by a single rounded rock (O) is equal to the
   number of rows from the rock to the south edge of the platform, including
   the row the rock is on. (Cube-shaped rocks (#) don't contribute to load.)
   So, the amount of load caused by each rock in each row is as follows:

 OOOO.#.O.. 10
 OO..#....#  9
 OO..O##..O  8
 O..#.OO...  7
 ........#.  6
 ..#....#.#  5
 ..O..#.O.O  4
 ..O.......  3
 #....###..  2
 #....#....  1

   The total load is the sum of the load caused by all of the rounded rocks.
   In this example, the total load is 136.

   Tilt the platform so that the rounded rocks all roll north. Afterward,
   what is the total load on the north support beams?

   Your puzzle answer was 108813.

--- Part Two ---

   The parabolic reflector dish deforms, but not in a way that focuses the
   beam. To do that, you'll need to move the rocks to the edges of the
   platform. Fortunately, a button on the side of the control panel labeled
   "spin cycle" attempts to do just that!

   Each cycle tilts the platform four times so that the rounded rocks roll
   north, then west, then south, then east. After each tilt, the rounded
   rocks roll as far as they can before the platform tilts in the next
   direction. After one cycle, the platform will have finished rolling the
   rounded rocks in those four directions in that order.

   Here's what happens in the example above after each of the first few
   cycles:

 After 1 cycle:
 .....#....
 ....#...O#
 ...OO##...
 .OO#......
 .....OOO#.
 .O#...O#.#
 ....O#....
 ......OOOO
 #...O###..
 #..OO#....

 After 2 cycles:
 .....#....
 ....#...O#
 .....##...
 ..O#......
 .....OOO#.
 .O#...O#.#
 ....O#...O
 .......OOO
 #..OO###..
 #.OOO#...O

 After 3 cycles:
 .....#....
 ....#...O#
 .....##...
 ..O#......
 .....OOO#.
 .O#...O#.#
 ....O#...O
 .......OOO
 #...O###.O
 #.OOO#...O

   This process should work if you leave it running long enough, but you're
   still worried about the north support beams. To make sure they'll survive
   for a while, you need to calculate the total load on the north support
   beams after 1000000000 cycles.

   In the above example, after 1000000000 cycles, the total load on the north
   support beams is 64.

   Run the spin cycle for 1000000000 cycles. Afterward, what is the total
   load on the north support beams?

   Your puzzle answer was 104533.

   Both parts of this puzzle are complete! They provide two gold stars: **

   At this point, you should [17]return to your Advent calendar and try
   another puzzle.

   If you still want to see it, you can [18]get your puzzle input.

   You can also [Shareon [19]Twitter [20]Mastodon] this puzzle.

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