Challenge 006 task 1

1 files changed, 57 insertions, 0 deletions

diff --git a/challenge-006/jo-37/perl/ch-1.pl b/challenge-006/jo-37/perl/ch-1.pl
new file mode 100755
index 0000000000..a54df67b3c
--- /dev/null
+++ b/challenge-006/jo-37/perl/ch-1.pl
@@ -0,0 +1,57 @@
+#!/usr/bin/perl -s
+
+use v5.16;
+use Test2::V0;
+
+our ($tests, $examples);
+
+run_tests() if $tests || $examples;	# does not return
+
+die <<EOS unless @ARGV;
+usage: $0 [-examples] [-tests] [--] [N...]
+
+-examples
+    run the examples from the challenge
+ 
+-tests
+    run some tests
+
+N...
+    sorted list of numbers
+
+EOS
+
+
+### Input and Output
+
+say compact(@ARGV);
+
+
+### Implementation
+
+# Join list elements with commas, replace commas between successive
+# numbers with hyphens, remove elements enclosed with hyphens and
+# finally replace hyphens between successive numbers with commas.
+sub compact {
+    join(',',  @_) =~ s/(\d+)\K,(?=(\d+))/$2 == $1 + 1 ? '-' : ','/egr
+    =~ s/-\d+(?=-)//gr
+    =~ s/(\d+)\K-(?=(\d+))/$2 == $1 + 1 ? ',' : '-'/egr;
+}
+
+
+### Examples and tests
+
+sub run_tests {
+    SKIP: {
+        skip "examples" unless $examples;
+
+        is compact(1,2,3,4,9,10,14,15,16), '1-4,9,10,14-16', 'example';
+    }
+
+    SKIP: {
+        skip "tests" unless $tests;
+	}
+
+    done_testing;
+    exit;
+}