adventofcode/23/1.pl
Yanick Champoux 86b2028152 part1
2017-12-23 15:06:05 -05:00

53 lines
774 B
Perl

use 5.20.0;
my @commands = <>;
my $i = 0;
my %reg;
my $last_played;
use experimental qw/ signatures /;
sub valof($x) {
$x =~ /\d/ ? $x : $reg{$x};
}
my $vr = qr/(-?\d+|.)/;
my $times;
use DDP;
my $t;
while() {
last if $i < 0 or $i > $#commands;
$_ = $commands[$i++];
# say $_;
if( /set (.) $vr/ ) {
$reg{$1} = valof($2);
}
elsif( /sub (.) $vr/ ) {
$reg{$1} -= valof($2);
}
elsif( /mul (.) $vr/ ) {
$reg{$1} *= valof($2);
$times++;
die if $times > 10_000;
# say $times;
}
elsif( /jnz (.) $vr/ ) {
$i += -1 + valof($2) if valof($1) != 0;
}
else { die "wut? $_"; }
# say $_;
# p %reg ;#unless $t++ % 10_000;
# my $dummy = <STDIN>;
}
say $times;