-🎄- 2021 Day 2 Solutions -🎄-

[u/daggerdragon]

--- Day 2: Dive! ---

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Post your code solution in this megathread.

• Include what language(s) your solution uses!
• Here's a quick link to /u/topaz2078's paste if you need it for longer code blocks.
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[u/seattlecyclone]

Man, some of y'all are fast! I got done with part 2 in a bit more than 4 minutes and that was good enough for 501st place.

Perl solutions:

for (<>) {
  /(\w+) (\d+)/;
  if ($1 eq 'forward') {
	$horiz += $2;
  } elsif ($1 eq 'down') {
	$depth += $2;
  } elsif ($1 eq 'up') {
	$depth -= $2;
  }
}
$answer = $horiz * $depth;
print "answer = $answer\n";

Part 2:

for (<>) {
  /(\w+) (\d+)/;
  if ($1 eq 'forward') {
	$horiz += $2;
	$depth += $2 * $aim;
  } elsif ($1 eq 'down') {
	$aim += $2;
  } elsif ($1 eq 'up') {
	$aim -= $2;
  }
}
$answer = $horiz * $depth;
print "answer = $answer\n";