From a3569417753c3b16944ef66851d248ffd0bdb507 Mon Sep 17 00:00:00 2001
From: arnesom <arne@bbop.org>
Date: Sat, 23 Jul 2022 23:58:33 +0200
Subject: Arne Sommer

---
 challenge-174/arne-sommer/blog.txt                 |  1 +
 challenge-174/arne-sommer/raku/ch-1.raku           | 20 +++++++++++++++++
 challenge-174/arne-sommer/raku/ch-2.raku           | 25 ++++++++++++++++++++++
 challenge-174/arne-sommer/raku/disarium-sequence   | 20 +++++++++++++++++
 challenge-174/arne-sommer/raku/permutation-ranking | 25 ++++++++++++++++++++++
 5 files changed, 91 insertions(+)
 create mode 100644 challenge-174/arne-sommer/blog.txt
 create mode 100755 challenge-174/arne-sommer/raku/ch-1.raku
 create mode 100755 challenge-174/arne-sommer/raku/ch-2.raku
 create mode 100755 challenge-174/arne-sommer/raku/disarium-sequence
 create mode 100755 challenge-174/arne-sommer/raku/permutation-ranking

diff --git a/challenge-174/arne-sommer/blog.txt b/challenge-174/arne-sommer/blog.txt
new file mode 100644
index 0000000000..61ccca2765
--- /dev/null
+++ b/challenge-174/arne-sommer/blog.txt
@@ -0,0 +1 @@
+https://raku-musings.com/disarmed-ranking.html
diff --git a/challenge-174/arne-sommer/raku/ch-1.raku b/challenge-174/arne-sommer/raku/ch-1.raku
new file mode 100755
index 0000000000..bd434dddaf
--- /dev/null
+++ b/challenge-174/arne-sommer/raku/ch-1.raku
@@ -0,0 +1,20 @@
+#! /usr/bin/env raku
+
+unit sub MAIN (Int $count where $count > 0 = 19);
+
+my $ds := (^Inf).grep( *.&is-disarium );
+
+say $ds[^$count].join(", ");
+
+sub is-disarium ($number)
+{
+  my $position = 0;
+  my $sum      = 0;
+
+  for $number.comb -> $digit
+  {
+    $sum += $digit ** ++$position;
+  }
+
+  return $sum == $number;
+}
diff --git a/challenge-174/arne-sommer/raku/ch-2.raku b/challenge-174/arne-sommer/raku/ch-2.raku
new file mode 100755
index 0000000000..4e4fc36cad
--- /dev/null
+++ b/challenge-174/arne-sommer/raku/ch-2.raku
@@ -0,0 +1,25 @@
+#! /usr/bin/env raku
+
+unit sub MAIN (*@i where all(@i) ~~ Int && ! @i.repeated, :$r, :v(:$verbose));
+
+say permutation2rank(@i);
+say rank2permutation(@i, $r);
+
+sub permutation2rank(@list)
+{
+  my @p = @list.sort.permutations;
+
+  for ^@p.elems -> $index
+  {
+    say ": $index -> @p[$index]" if $verbose;
+    return $index if @p[$index] cmp @list == 0;
+  }
+}
+
+sub rank2permutation(@list, $index)
+{
+  my @p = @list.sort.permutations;
+
+  return @p[$index];
+
+}
\ No newline at end of file
diff --git a/challenge-174/arne-sommer/raku/disarium-sequence b/challenge-174/arne-sommer/raku/disarium-sequence
new file mode 100755
index 0000000000..bd434dddaf
--- /dev/null
+++ b/challenge-174/arne-sommer/raku/disarium-sequence
@@ -0,0 +1,20 @@
+#! /usr/bin/env raku
+
+unit sub MAIN (Int $count where $count > 0 = 19);
+
+my $ds := (^Inf).grep( *.&is-disarium );
+
+say $ds[^$count].join(", ");
+
+sub is-disarium ($number)
+{
+  my $position = 0;
+  my $sum      = 0;
+
+  for $number.comb -> $digit
+  {
+    $sum += $digit ** ++$position;
+  }
+
+  return $sum == $number;
+}
diff --git a/challenge-174/arne-sommer/raku/permutation-ranking b/challenge-174/arne-sommer/raku/permutation-ranking
new file mode 100755
index 0000000000..4e4fc36cad
--- /dev/null
+++ b/challenge-174/arne-sommer/raku/permutation-ranking
@@ -0,0 +1,25 @@
+#! /usr/bin/env raku
+
+unit sub MAIN (*@i where all(@i) ~~ Int && ! @i.repeated, :$r, :v(:$verbose));
+
+say permutation2rank(@i);
+say rank2permutation(@i, $r);
+
+sub permutation2rank(@list)
+{
+  my @p = @list.sort.permutations;
+
+  for ^@p.elems -> $index
+  {
+    say ": $index -> @p[$index]" if $verbose;
+    return $index if @p[$index] cmp @list == 0;
+  }
+}
+
+sub rank2permutation(@list, $index)
+{
+  my @p = @list.sort.permutations;
+
+  return @p[$index];
+
+}
\ No newline at end of file
-- 
cgit