Solution to task 1

1 files changed, 65 insertions, 0 deletions

diff --git a/challenge-268/jo-37/perl/ch-1.pl b/challenge-268/jo-37/perl/ch-1.pl
new file mode 100755
index 0000000000..de0aa50546
--- /dev/null
+++ b/challenge-268/jo-37/perl/ch-1.pl
@@ -0,0 +1,65 @@
+#!/usr/bin/perl -s
+
+use v5.24;
+use Test2::V0 '!float';
+use PDL;
+use experimental 'signatures';
+
+our ($tests, $examples);
+
+run_tests() if $tests || $examples;	# does not return
+
+die <<EOS unless @ARGV == 2;
+usage: $0 [-examples] [-tests] [--] [ListX ListY]
+
+-examples
+    run the examples from the challenge
+ 
+-tests
+    run some tests
+
+ListX ListY
+    two lists of comma separated numbers
+
+EOS
+
+
+### Input and Output
+
+say magic_number(map [split /,/], @ARGV) // 'no magic number';
+
+
+### Implementation
+#
+# For details see:
+# https://github.sommrey.de/the-bears-den/2024/05/10/ch-268.html#task-1
+
+
+sub magic_number ($x, $y) {
+	my ($min, $max) = minmax pdl($y)->qsort - pdl($x)->qsort;
+    $min == $max ? $min : undef;
+}
+
+
+### Examples and tests
+
+sub run_tests {
+    SKIP: {
+        skip "examples" unless $examples;
+
+        is magic_number([3, 7, 5], [9, 5, 7]), 2, 'example 1';
+        is magic_number([1, 2, 1], [5, 4, 4]), 3, 'example 2';
+        is magic_number([2], [5]), 3, 'example 3';
+    }
+
+    SKIP: {
+        skip "tests" unless $tests;
+
+        is magic_number([1, 2], [3, 5]), U(), 'no magic number';
+        is magic_number([1, 2], [2, 1]), 0, 'same numbers';
+        is magic_number([4, 3], [1, 2]), -2, 'negative magic number';
+	}
+
+    done_testing;
+    exit;
+}