Add solutions to 242: Missing Numbers & Flip Matrix by E. Choroba

In Missing Numbers, I added the [] for no missing elements. The added
test case shows why I think it's needed.

2 files changed, 52 insertions, 0 deletions

diff --git a/challenge-242/e-choroba/perl/ch-1.pl b/challenge-242/e-choroba/perl/ch-1.pl
new file mode 100755
index 0000000000..93b46b9b45
--- /dev/null
+++ b/challenge-242/e-choroba/perl/ch-1.pl
@@ -0,0 +1,26 @@
+#!/usr/bin/perl
+use warnings;
+use strict;
+use experimental qw( signatures );
+
+use Tie::IxHash;
+
+sub missing_members($arr1, $arr2) {
+    tie my %seen, 'Tie::IxHash';
+    for my $i (0, 1) {
+        $seen{$_}[$i] = 1 for @{ ($arr1, $arr2)[$i] };
+    }
+    my @missing = ([], []);
+    for my $e (keys %seen) {
+        push @{ $missing[ ! $seen{$e}[0] ] }, $e
+            unless 2 == grep $_, @{ $seen{$e} };
+    }
+    return \@missing
+}
+
+use Test2::V0;
+plan 2 + 1;
+
+is missing_members([1, 2, 3], [2, 4, 6]), [[1, 3], [4, 6]], 'Example 1';
+is missing_members([1, 2, 3, 3], [1, 1, 2, 2]), [[3], []], 'Example 2';
+is missing_members([1, 1, 2, 2], [1, 2, 3, 3]), [[], [3]], 'First empty';
diff --git a/challenge-242/e-choroba/perl/ch-2.pl b/challenge-242/e-choroba/perl/ch-2.pl
new file mode 100755
index 0000000000..199eb685ce
--- /dev/null
+++ b/challenge-242/e-choroba/perl/ch-2.pl
@@ -0,0 +1,26 @@
+#!/usr/bin/perl
+use warnings;
+use strict;
+use experimental qw( signatures );
+
+use PDL;
+
+sub flip_matrix($m) {
+    ! pdl($m)->slice('-1:0:0')
+}
+
+use Test::More tests => 3;
+
+is_deeply flip_matrix("[1 1 0]\n[0 1 1]\n[0 0 1]")->unpdl,
+    [[1, 0, 0], [0, 0, 1], [0, 1, 1]],
+    'Unnamed example';
+
+is_deeply flip_matrix([[1, 1, 0], [1, 0, 1], [0, 0, 0]])->unpdl,
+    [[1, 0, 0], [0, 1, 0], [1, 1, 1]],
+    'Example 1';
+
+is_deeply flip_matrix(
+    [[1, 1, 0, 0], [1, 0, 0, 1], [0, 1, 1, 1], [1, 0, 1, 0]]
+)->unpdl,
+    [[1, 1, 0, 0], [0, 1, 1, 0], [0, 0, 0, 1], [1, 0, 1, 0]],
+    'Example 2';