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+** --- Day 23: Crab Cups ---
+The small crab challenges /you/ to a game! The crab is going to mix up
+some cups, and you have to predict where they'll end up.
+
+The cups will be arranged in a circle and labeled /clockwise/ (your
+puzzle input). For example, if your labeling were =32415=, there would
+be five cups in the circle; going clockwise around the circle from the
+first cup, the cups would be labeled =3=, =2=, =4=, =1=, =5=, and then
+back to =3= again.
+
+Before the crab starts, it will designate the first cup in your list as
+the /current cup/. The crab is then going to do /100 moves/.
+
+Each /move/, the crab does the following actions:
+
+- The crab picks up the /three cups/ that are immediately /clockwise/ of
+  the /current cup/. They are removed from the circle; cup spacing is
+  adjusted as necessary to maintain the circle.
+- The crab selects a /destination cup/: the cup with a /label/ equal to
+  the /current cup's/ label minus one. If this would select one of the
+  cups that was just picked up, the crab will keep subtracting one until
+  it finds a cup that wasn't just picked up. If at any point in this
+  process the value goes below the lowest value on any cup's label, it
+  /wraps around/ to the highest value on any cup's label instead.
+- The crab places the cups it just picked up so that they are
+  /immediately clockwise/ of the destination cup. They keep the same
+  order as when they were picked up.
+- The crab selects a new /current cup/: the cup which is immediately
+  clockwise of the current cup.
+
+For example, suppose your cup labeling were =389125467=. If the crab
+were to do merely 10 moves, the following changes would occur:
+
+#+BEGIN_EXAMPLE
+  -- move 1 --
+  cups: (3) 8  9  1  2  5  4  6  7
+  pick up: 8, 9, 1
+  destination: 2
+
+  -- move 2 --
+  cups:  3 (2) 8  9  1  5  4  6  7
+  pick up: 8, 9, 1
+  destination: 7
+
+  -- move 3 --
+  cups:  3  2 (5) 4  6  7  8  9  1
+  pick up: 4, 6, 7
+  destination: 3
+
+  -- move 4 --
+  cups:  7  2  5 (8) 9  1  3  4  6
+  pick up: 9, 1, 3
+  destination: 7
+
+  -- move 5 --
+  cups:  3  2  5  8 (4) 6  7  9  1
+  pick up: 6, 7, 9
+  destination: 3
+
+  -- move 6 --
+  cups:  9  2  5  8  4 (1) 3  6  7
+  pick up: 3, 6, 7
+  destination: 9
+
+  -- move 7 --
+  cups:  7  2  5  8  4  1 (9) 3  6
+  pick up: 3, 6, 7
+  destination: 8
+
+  -- move 8 --
+  cups:  8  3  6  7  4  1  9 (2) 5
+  pick up: 5, 8, 3
+  destination: 1
+
+  -- move 9 --
+  cups:  7  4  1  5  8  3  9  2 (6)
+  pick up: 7, 4, 1
+  destination: 5
+
+  -- move 10 --
+  cups: (5) 7  4  1  8  3  9  2  6
+  pick up: 7, 4, 1
+  destination: 3
+
+  -- final --
+  cups:  5 (8) 3  7  4  1  9  2  6
+#+END_EXAMPLE
+
+In the above example, the cups' values are the labels as they appear
+moving clockwise around the circle; the /current cup/ is marked with
+=( )=.
+
+After the crab is done, what order will the cups be in? Starting /after
+the cup labeled =1=/, collect the other cups' labels clockwise into a
+single string with no extra characters; each number except =1= should
+appear exactly once. In the above example, after 10 moves, the cups
+clockwise from =1= are labeled =9=, =2=, =6=, =5=, and so on, producing
+/=92658374=/. If the crab were to complete all 100 moves, the order
+after cup =1= would be /=67384529=/.
+
+Using your labeling, simulate 100 moves. /What are the labels on the
+cups after cup =1=?/
+
+Your puzzle answer was =75893264=.
+
+** --- Part Two ---
+Due to what you can only assume is a mistranslation (you're not exactly
+fluent in Crab), you are quite surprised when the crab starts arranging
+/many/ cups in a circle on your raft - /one million/ (=1000000=) in
+total.
+
+Your labeling is still correct for the first few cups; after that, the
+remaining cups are just numbered in an increasing fashion starting from
+the number after the highest number in your list and proceeding one by
+one until one million is reached. (For example, if your labeling were
+=54321=, the cups would be numbered =5=, =4=, =3=, =2=, =1=, and then
+start counting up from =6= until one million is reached.) In this way,
+every number from one through one million is used exactly once.
+
+After discovering where you made the mistake in translating Crab
+Numbers, you realize the small crab isn't going to do merely 100 moves;
+the crab is going to do /ten million/ (=10000000=) moves!
+
+The crab is going to hide your /stars/ - one each - under the /two cups
+that will end up immediately clockwise of cup =1=/. You can have them if
+you predict what the labels on those cups will be when the crab is
+finished.
+
+In the above example (=389125467=), this would be =934001= and then
+=159792=; multiplying these together produces /=149245887792=/.
+
+Determine which two cups will end up immediately clockwise of cup =1=.
+/What do you get if you multiply their labels together?/
+
+Your puzzle answer was =38162588308=.
+
+Both parts of this puzzle are complete! They provide two gold stars: **