## --- Day 10: Elves Look, Elves Say ---

Today, the Elves are playing a game called look-and-say. They take turns making sequences by reading aloud the previous sequence and using that reading as the next sequence. For example, `211`

is read as "one two, two ones", which becomes `1221`

(`1`

`2`

, `2`

`1`

s).

Look-and-say sequences are generated iteratively, using the previous value as input for the next step. For each step, take the previous value, and replace each run of digits (like `111`

) with the number of digits (`3`

) followed by the digit itself (`1`

).

For example:

`1`

becomes`11`

(`1`

copy of digit`1`

).`11`

becomes`21`

(`2`

copies of digit`1`

).`21`

becomes`1211`

(one`2`

followed by one`1`

).`1211`

becomes`111221`

(one`1`

, one`2`

, and two`1`

s).`111221`

becomes`312211`

(three`1`

s, two`2`

s, and one`1`

).

Starting with the digits in your puzzle input, apply this process 40 times. What is *the length of the result*?