aoc-2021-rust

Advent of Code 2021 Solutions in Rust
git clone https://git.sinitax.com/sinitax/aoc-2021-rust
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part1 (1507B)

      1--- Day 2: Dive! ---
      2
      3Now, you need to figure out how to pilot this thing.
      4
      5It seems like the submarine can take a series of commands like forward 1, down 2, or up 3:
      6
      7
      8 - forward X increases the horizontal position by X units.
      9
     10 - down X increases the depth by X units.
     11
     12 - up X decreases the depth by X units.
     13
     14
     15Note that since you're on a submarine, down and up affect your depth, and so they have
     16the opposite result of what you might expect.
     17
     18The submarine seems to already have a planned course (your puzzle input). You should probably figure
     19out where it's going. For example:
     20
     21forward 5
     22down 5
     23forward 8
     24up 3
     25down 8
     26forward 2
     27
     28Your horizontal position and depth both start at 0. The steps above would then modify them as
     29follows:
     30
     31
     32 - forward 5 adds 5 to your horizontal position, a total of 5.
     33
     34 - down 5 adds 5 to your depth, resulting in a value of 5.
     35
     36 - forward 8 adds 8 to your horizontal position, a total of 13.
     37
     38 - up 3 decreases your depth by 3, resulting in a value of 2.
     39
     40 - down 8 adds 8 to your depth, resulting in a value of 10.
     41
     42 - forward 2 adds 2 to your horizontal position, a total of 15.
     43
     44
     45After following these instructions, you would have a horizontal position of 15 and a depth of 10.
     46(Multiplying these together produces 150.)
     47
     48Calculate the horizontal position and depth you would have after following the planned course.
     49What do you get if you multiply your final horizontal position by your final depth?
     50
     51