Advent of Code

--- Day 1: No Time for a Taxicab ---

   Santa's sleigh uses a very high-precision clock to guide its movements, and
   the clock's oscillator is regulated by stars. Unfortunately, the stars have
   been stolen... by the Easter Bunny. To save Christmas, Santa needs you to
   retrieve all fifty stars by December 25th.

   Collect stars by solving puzzles. Two puzzles will be made available on each
   day in the advent calendar; the second puzzle is unlocked when you complete
   the first. Each puzzle grants one star. Good luck!

   You're airdropped near Easter Bunny Headquarters in a city somewhere.
   "Near", unfortunately, is as close as you can get - the instructions on the
   Easter Bunny Recruiting Document the Elves intercepted start here, and
   nobody had time to work them out further.

   The Document indicates that you should start at the given coordinates (where
   you just landed) and face North. Then, follow the provided sequence: either
   turn left (L) or right (R) 90 degrees, then walk forward the given number of
   blocks, ending at a new intersection.

   There's no time to follow such ridiculous instructions on foot, though, so
   you take a moment and work out the destination. Given that you can only walk
   on the street grid of the city, how far is the shortest path to the
   destination?

   For example:

     • Following R2, L3 leaves you 2 blocks East and 3 blocks North, or 5
       blocks away.

     • R2, R2, R2 leaves you 2 blocks due South of your starting position,
       which is 2 blocks away.

     • R5, L5, R5, R3 leaves you 12 blocks away.

   How many blocks away is Easter Bunny HQ?

   Your puzzle answer was 243.

--- Part Two ---

   Then, you notice the instructions continue on the back of the Recruiting
   Document. Easter Bunny HQ is actually at the first location you visit twice.

   For example, if your instructions are R8, R4, R4, R8, the first location you
   visit twice is 4 blocks away, due East.

   How many blocks away is the first location you visit twice?

   Your puzzle answer was 142.

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

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