Add code and description for D2P1 and D2P1

day_02/info.md

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+https://adventofcode.com/2021/day/2
+
+---
+
+## --- 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 by X units.
+ - `down X` increases the depth by X units.
+ - `up X` decreases the depth by X 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` adds `5` to your horizontal position, a total of `5`.
+ - `down 5` adds `5` to your depth, resulting in a value of `5`.
+ - `forward 8` adds `8` to your horizontal position, a total of `13`.
+ - `up 3` decreases your depth by `3`, resulting in a value of `2`.
+ - `down 8` adds `8` to your depth, resulting in a value of `10`.
+ - `forward 2` adds `2` to your horizontal position, a total of `15`.
+
+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?
+
+## --- Part Two ---
+Based on your calculations, the planned course doesn't seem to make any sense.
+You find the submarine manual and discover that the process is actually slightly
+more complicated.
+
+In addition to horizontal position and depth, you'll also need to track a third
+value, `aim`, which also starts at `0`. The commands also mean something entirely
+different than you first thought:
+
+ - `down X` increases your aim by X units.
+ - `up X` decreases your aim by X units.
+ - `forward X` does two things:
+   - It increases your horizontal position by X units.
+   - It increases your depth by your aim multiplied by X.
+
+Again note that since you're on a submarine, down and up do the opposite of what
+you might expect: "down" means aiming in the positive direction.
+
+Now, the above example does something different:
+
+ - `forward 5` adds `5` to your horizontal position, a total of `5`. Because your aim is `0`, your depth does not change.
+ - `down 5` adds `5` to your aim, resulting in a value of `5`.
+ - `forward 8` adds `8` to your horizontal position, a total of `13`. Because your aim is `5`, your depth increases by `8*5=40`.
+ - `up 3` decreases your aim by `3`, resulting in a value of `2`.
+ - `down 8` adds `8` to your aim, resulting in a value of `10`.
+ - `forward 2` adds `2` to your horizontal position, a total of `15`. Because your aim is `10`, your depth increases by `2*10=20` to a total of `60`.
+
+After following these new instructions, you would have a horizontal position of
+`15` and a depth of `60`. (Multiplying these produces `900`.)
+
+Using this new interpretation of the commands, 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?

day_02/python/part_1.py

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+depth = 0
+distance = 0
+
+with open("../input", "r") as file:
+	instructions = file.read().split("\n")
+
+# Follow each instruction
+for instruction in instructions:
+
+	# Parse the instruction into usable data
+	direction, magnitude = instruction.split(" ")
+	magnitude = int(magnitude)
+
+	# Modify the submarine coordinates as needed
+	if direction == "forward": distance += magnitude
+	elif direction == "up": depth -= magnitude
+	else: depth += magnitude
+
+print(f"""Distance: {distance}m
+Depth: {depth}m
+
+Puzzle Answer: {distance * depth}""")

day_02/python/part_2.py

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+depth = 0
+distance = 0
+aim = 0
+
+with open("../input", "r") as file:
+	instructions = file.read().split("\n")
+
+# Follow each instruction
+for instruction in instructions:
+
+	# Parse the instruction into usable data
+	direction, magnitude = instruction.split(" ")
+	magnitude = int(magnitude)
+
+	# Modify the submarine coordinates as needed
+	if direction == "forward":
+		distance += magnitude
+		depth += aim * magnitude
+	elif direction == "up":
+		aim -= magnitude
+	else:
+		aim += magnitude
+
+print(f"""Distance: {distance}m
+Depth: {depth}m
+Aim: {aim}
+
+Puzzle Answer: {distance * depth}""")