Moved 2020 to a subdir

[aoc.git] / 2020 / 1.pl

diff --git a/2020/1.pl b/2020/1.pl
new file mode 100755 (executable)
index 0000000..2052140
--- /dev/null
+++ b/2020/1.pl
@@ -0,0 +1,20 @@
+#!/usr/bin/perl -w
+
+use strict;
+
+my @nums = sort { $a <=> $b } <>;
+chomp @nums;
+
+while (@nums > 1) {
+       print "Nums: ", join(' ', @nums), "\n";
+       my $cmp = $nums[0] + $nums[-1] <=> 2020;
+       if ($cmp < 0) {
+               shift @nums;
+       } elsif ($cmp == 0) {
+               print "$nums[0]*$nums[-1]=", $nums[0]*$nums[-1], "\n";
+               last;
+       } else {
+               pop @nums;
+       }
+}
+