copy pasting the rules from last year’s thread:
Rules: no spoilers.
The other rules are made up aswe go along.
Share code by link to a forge, home page, pastebin (Eric Wastl has one here) or code section in a comment.
1 point
Yay, day 3 with Regexp magic.
Day 3
open(FH, '<', $ARGV[0]) or die $!;
my $sum = 0;
my $sum2 = 0;
my $enabled = 1;
while (<FH>) {
while ($_ =~ /(?:mul\((\d{1,3}),(\d{1,3})\)|(do)\(\)|(don\'t)\(\))/g) {
$enabled = 1 if $3;
$enabled = 0 if $4;
$sum += $1 * $2 if $1 && $2;
$sum2 += $1 * $2 if $enabled && $1 && $2;
}
}
close(FH);
print "Part 1: $sum\n";
print "Part 2: $sum2\n";
