X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?p=aoc2020.git;a=blobdiff_plain;f=28.pl;fp=28.pl;h=edf339ee7a7a65cc6c6a826b75178b0c3217623f;hp=0000000000000000000000000000000000000000;hb=0c26b846783563f208ecedc83fe18f12f8f24293;hpb=b957ac325434a1623becbe1850127821a94c38fe

diff --git a/28.pl b/28.pl
new file mode 100755
index 0000000..edf339e
--- /dev/null
+++ b/28.pl
@@ -0,0 +1,39 @@
+#!/usr/bin/perl -w
+
+use strict;
+no warnings 'portable';
+
+my %mem;
+
+my ($floatm, $orm);
+while (<>) {
+	chomp;
+	if (/mask = (\S+)/) {
+		($orm, $floatm) = ($1, $1);
+		$floatm =~ s/1/0/g;
+		$orm  =~ s/X/0/g; $orm  = oct "0b$orm";
+		next;
+	}
+	if (/mem\[(\d+)\] = (\d+)/) {
+		my $data = $2;
+		for my $addr (addr2list($1|$orm, $floatm)) {
+			$mem{$addr} = $data;
+			# print "mem[$addr=", pack("b*", $addr),"] = $2\n";
+		}
+	}
+}
+
+my $sum;
+for (keys %mem) { $sum += $mem{$_} };
+print "Sum=$sum\n";
+
+sub addr2list {
+	my ($addr, $mask) = @_;
+	if ($mask =~ s/X/0/) {
+		my $off = length $';
+		return (addr2list($addr | (1 << $off), $mask),
+			addr2list($addr & ~(1 << $off), $mask));
+	} else {
+		return ($addr);
+	}
+}