]> www.fi.muni.cz Git - aoc.git/blobdiff - 2020/2.pl
Moved 2020 to a subdir
[aoc.git] / 2020 / 2.pl
diff --git a/2020/2.pl b/2020/2.pl
new file mode 100755 (executable)
index 0000000..d950fae
--- /dev/null
+++ b/2020/2.pl
@@ -0,0 +1,20 @@
+#!/usr/bin/perl -w
+
+use strict;
+
+my @nums = sort { $a <=> $b } <>;
+chomp @nums;
+
+my %is_listed = map { $_ => 1 } @nums;
+
+for my $i (0 .. $#nums-1) {
+       for my $j ($i .. $#nums) {
+               my $rest = 2020-$nums[$i]-$nums[$j];
+               if ($rest > 0 && $is_listed{$rest} && $rest != $nums[$i]
+                       && $rest != $nums[$j]) {
+                       print "$nums[$i]*$nums[$j]*$rest=", $nums[$i]*$nums[$j]*$rest, "\n";
+                       last;
+               }
+       }
+}
+