Merge pull request #7555 from polettix/polettix/pwc203

Add polettix's solution to challenge-203

6 files changed, 92 insertions, 0 deletions

diff --git a/challenge-203/polettix/blog.txt b/challenge-203/polettix/blog.txt
new file mode 100644
index 0000000000..fad6941e2b
--- /dev/null
+++ b/challenge-203/polettix/blog.txt
@@ -0,0 +1 @@
+https://etoobusy.polettix.it/2023/02/09/pwc203-special-quadruplets/
diff --git a/challenge-203/polettix/blog1.txt b/challenge-203/polettix/blog1.txt
new file mode 100644
index 0000000000..8ebf035315
--- /dev/null
+++ b/challenge-203/polettix/blog1.txt
@@ -0,0 +1 @@
+https://etoobusy.polettix.it/2023/02/10/pwc203-copy-directory/
diff --git a/challenge-203/polettix/perl/ch-1.pl b/challenge-203/polettix/perl/ch-1.pl
new file mode 100644
index 0000000000..6f799fe90a
--- /dev/null
+++ b/challenge-203/polettix/perl/ch-1.pl
@@ -0,0 +1,46 @@
+#!/usr/bin/env perl
+use v5.24;
+use warnings;
+use experimental 'signatures';
+no warnings 'experimental::signatures';
+use List::Util 'sum';
+
+say special_quadruplets(@ARGV);
+
+sub special_quadruplets (@nums) {
+   my $it = combinations_iterator(4, @nums);
+   my $count = 0;
+   while (my ($c, undef) = $it->()) {
+      ++$count if sum($c->@[0..2]) == $c->[3];
+   }
+   return $count;
+}
+
+sub combinations_iterator ($k, @items) {
+   my @indexes = (0 .. ($k - 1));
+   my $n = @items;
+   return sub {
+      return unless @indexes;
+      my (@combination, @remaining);
+      my $j = 0;
+      for my $i (0 .. ($n - 1)) {
+         if ($j < $k && $i == $indexes[$j]) {
+            push @combination, $items[$i];
+            ++$j;
+         }
+         else {
+            push @remaining, $items[$i];
+         }
+      }
+      for my $incc (reverse(-1, 0 .. ($k - 1))) {
+         if ($incc < 0) {
+            @indexes = (); # finished!
+         }
+         elsif ((my $v = $indexes[$incc]) < $incc - $k + $n) {
+            $indexes[$_] = ++$v for $incc .. ($k - 1);
+            last;
+         }
+      }
+      return (\@combination, \@remaining);
+   }
+}
diff --git a/challenge-203/polettix/perl/ch-2.pl b/challenge-203/polettix/perl/ch-2.pl
new file mode 100644
index 0000000000..ecaa623656
--- /dev/null
+++ b/challenge-203/polettix/perl/ch-2.pl
@@ -0,0 +1,26 @@
+#!/usr/bin/env perl
+use v5.24;
+use warnings;
+use English '-no_match_vars';
+use experimental 'signatures';
+no warnings 'experimental::signatures';
+
+use File::Spec::Functions qw< splitpath splitdir catdir catpath >;
+use File::Path qw< make_path >;
+
+copy_directory(@ARGV);
+
+sub copy_directory ($from, $to) {
+   my ($fv, $fds) = splitpath($from, 'no-file');
+   my ($tv, $tds) = splitpath($to, 'no-file');
+   opendir my $dh, $from or die "opendir('$from'): $OS_ERROR";
+   for my $item (readdir($dh)) {
+      next if ($item eq '.') || ($item eq '..');
+      my $source = catpath($fv, $fds, $item);
+      next unless -d $source;
+      my (undef, undef, $mode) = stat($source);
+      my $target = catpath($tv, $tds, $item);
+      make_path($target, {mode => $mode});
+      __SUB__->($source, $target);
+   }
+}
diff --git a/challenge-203/polettix/raku/ch-1.raku b/challenge-203/polettix/raku/ch-1.raku
new file mode 100644
index 0000000000..8d66579dd0
--- /dev/null
+++ b/challenge-203/polettix/raku/ch-1.raku
@@ -0,0 +1,7 @@
+#!/usr/bin/env raku
+use v6;
+sub MAIN (*@args) { put special-quadruplets(@args) }
+
+sub special-quadruplets (@nums) {
+   combinations(@nums, 4).grep({$_[0..2].sum == $_[3]}).elems
+}
diff --git a/challenge-203/polettix/raku/ch-2.raku b/challenge-203/polettix/raku/ch-2.raku
new file mode 100644
index 0000000000..c8995907ef
--- /dev/null
+++ b/challenge-203/polettix/raku/ch-2.raku
@@ -0,0 +1,11 @@
+#!/usr/bin/env raku
+use v6;
+sub MAIN ($from, $to) { copy-directory($from, $to) }
+
+sub copy-directory (IO::Path() $from, IO::Path() $to) {
+   for $from.dir -> $source {
+      next unless $source.d;
+      my $target = $to.child($source.basename).mkdir($source.mode);
+      samewith($source, $target);
+   }
+}