Advent of Code

--- Day 23: Experimental Emergency Teleportation ---

   Using your torch to search the darkness of the rocky cavern, you finally
   locate the man's friend: a small reindeer.

   You're not sure how it got so far in this cave. It looks sick - too sick to
   walk - and too heavy for you to carry all the way back. Sleighs won't be
   invented for another 1500 years, of course.

   The only option is experimental emergency teleportation.

   You hit the "experimental emergency teleportation" button on the device and
   push I accept the risk on no fewer than 18 different warning messages.
   Immediately, the device deploys hundreds of tiny nanobots which fly around
   the cavern, apparently assembling themselves into a very specific formation.
   The device lists the X,Y,Z position (pos) for each nanobot as well as its
   signal radius (r) on its tiny screen (your puzzle input).

   Each nanobot can transmit signals to any integer coordinate which is a
   distance away from it less than or equal to its signal radius (as measured
   by Manhattan distance). Coordinates a distance away of less than or equal to
   a nanobot's signal radius are said to be in range of that nanobot.

   Before you start the teleportation process, you should determine which
   nanobot is the strongest (that is, which has the largest signal radius) and
   then, for that nanobot, the total number of nanobots that are in range of
   it, including itself.

   For example, given the following nanobots:

 pos=<0,0,0>, r=4 pos=<1,0,0>, r=1 pos=<4,0,0>, r=3 pos=<0,2,0>, r=1
 pos=<0,5,0>, r=3 pos=<0,0,3>, r=1 pos=<1,1,1>, r=1 pos=<1,1,2>, r=1
 pos=<1,3,1>, r=1

   The strongest nanobot is the first one (position 0,0,0) because its signal
   radius, 4 is the largest. Using that nanobot's location and signal radius,
   the following nanobots are in or out of range:

     • The nanobot at 0,0,0 is distance 0 away, and so it is in range. • The
     nanobot at 1,0,0 is distance 1 away, and so it is in range. • The nanobot
     at 4,0,0 is distance 4 away, and so it is in range. • The nanobot at 0,2,0
     is distance 2 away, and so it is in range. • The nanobot at 0,5,0 is
     distance 5 away, and so it is not in range. • The nanobot at 0,0,3 is
     distance 3 away, and so it is in range. • The nanobot at 1,1,1 is distance
     3 away, and so it is in range. • The nanobot at 1,1,2 is distance 4 away,
     and so it is in range. • The nanobot at 1,3,1 is distance 5 away, and so
     it is not in range.

   In this example, in total, 7 nanobots are in range of the nanobot with the
   largest signal radius.

   Find the nanobot with the largest signal radius. How many nanobots are in
   range of its signals?

   Your puzzle answer was 599.

--- Part Two ---

   Now, you just need to figure out where to position yourself so that you're
   actually teleported when the nanobots activate.

   To increase the probability of success, you need to find the coordinate
   which puts you in range of the largest number of nanobots. If there are
   multiple, choose one closest to your position (0,0,0, measured by manhattan
   distance).

   For example, given the following nanobot formation:

 pos=<10,12,12>, r=2 pos=<12,14,12>, r=2 pos=<16,12,12>, r=4 pos=<14,14,14>,
 r=6 pos=<50,50,50>, r=200 pos=<10,10,10>, r=5

   Many coordinates are in range of some of the nanobots in this formation.
   However, only the coordinate 12,12,12 is in range of the most nanobots: it
   is in range of the first five, but is not in range of the nanobot at
   10,10,10. (All other coordinates are in range of fewer than five nanobots.)
   This coordinate's distance from 0,0,0 is 36.

   Find the coordinates that are in range of the largest number of nanobots.
   What is the shortest manhattan distance between any of those points and
   0,0,0?

   Your puzzle answer was 94481130.

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

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

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

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