--- Day 2: Dive! ---
Now, you need to figure out how to pilot this thing.
It seems like the submarine can take a series of commands like forward 1
, down 2
, or up 3
:
forward X
increases the horizontal position byX
units.down X
increases the depth byX
units.up X
decreases the depth byX
units.
Note that since you're on a submarine, down
and up
affect your depth, and so they have the opposite result of what you might expect.
The submarine seems to already have a planned course (your puzzle input). You should probably figure out where it's going. For example:
forward 5
down 5
forward 8
up 3
down 8
forward 2
Your horizontal position and depth both start at 0
. The steps above would then modify them as follows:
forward 5
adds5
to your horizontal position, a total of5
.down 5
adds5
to your depth, resulting in a value of5
.forward 8
adds8
to your horizontal position, a total of13
.up 3
decreases your depth by3
, resulting in a value of2
.down 8
adds8
to your depth, resulting in a value of10
.forward 2
adds2
to your horizontal position, a total of15
.
After following these instructions, you would have a horizontal position of 15
and a depth of 10
. (Multiplying these together produces 150
.)
Calculate the horizontal position and depth you would have after following the planned course. What do you get if you multiply your final horizontal position by your final depth?