Add solution for challenge-141 task 2

1 files changed, 49 insertions, 0 deletions

diff --git a/challenge-141/alexander-pankoff/perl/ch-2.pl b/challenge-141/alexander-pankoff/perl/ch-2.pl
new file mode 100644
index 0000000000..a2d1d0bea6
--- /dev/null
+++ b/challenge-141/alexander-pankoff/perl/ch-2.pl
@@ -0,0 +1,49 @@
+use strict;
+use warnings;
+use feature qw'say signatures';
+no warnings 'experimental::signatures';
+
+use List::Util qw(reduce);
+
+use constant DEBUG => $ENV{DEBUG} // 0;
+
+run() unless caller();
+
+sub run() {
+    my $m = prompt_for_integer('m');
+    my $n = prompt_for_integer('n');
+
+    my @possible_integers = numbers_from_digits($m);
+    my @divisible_by_n    = grep { $_ % $n == 0 } @possible_integers;
+    say scalar @divisible_by_n;
+}
+
+sub numbers_from_digits($x) {
+    my @digits  = split( '', $x );
+    my $numbers = reduce(
+        sub {
+            my $digit = $digits[$b];
+            return [
+                @$a,    #
+                $digit,
+                ( grep { length $_ < @digits } map { $_ . $digit } @$a ),
+            ];
+        },
+        [],
+        0 .. $#digits
+    );
+
+    return @$numbers;
+}
+
+sub prompt_for_integer($name) {
+    say "Enter positive integer '$name'";
+    chomp( my $number = <STDIN> );
+
+    if ( $number !~ m/^\d+$/ || $number < 1 ) {
+        say "Invalid integer.";
+        return prompt_for_integer($name);
+    }
+
+    return $number;
+}