Merge pull request #5761 from polettix/polettix/pwc155

Add polettix's solution to challenge-155

8 files changed, 150 insertions, 0 deletions

diff --git a/challenge-155/polettix/blog.txt b/challenge-155/polettix/blog.txt
new file mode 100644
index 0000000000..7ae6c3035b
--- /dev/null
+++ b/challenge-155/polettix/blog.txt
@@ -0,0 +1 @@
+https://github.polettix.it/ETOOBUSY/2022/03/09/pwc155-fortunate-numbers/
diff --git a/challenge-155/polettix/blog1.txt b/challenge-155/polettix/blog1.txt
new file mode 100644
index 0000000000..68c1c1e8a3
--- /dev/null
+++ b/challenge-155/polettix/blog1.txt
@@ -0,0 +1 @@
+https://github.polettix.it/ETOOBUSY/2022/03/10/pisano-period/
diff --git a/challenge-155/polettix/perl/ch-1.pl b/challenge-155/polettix/perl/ch-1.pl
new file mode 100644
index 0000000000..f1995e598e
--- /dev/null
+++ b/challenge-155/polettix/perl/ch-1.pl
@@ -0,0 +1,39 @@
+#!/usr/bin/env perl
+use v5.24;
+use warnings;
+use experimental 'signatures';
+no warnings 'experimental::signatures';
+
+use FindBin '$Bin';
+use lib "$Bin/local/lib/perl5";
+use ntheory qw< is_prime next_prime >;
+use List::MoreUtils 'uniq';
+use bigint;
+
+say join ', ', first_fortunate_numbers(shift || 8);
+
+sub first_fortunate_numbers ($n) {
+   my $it = fortunate_numbers_it();
+   my (@cleared, @seen);
+   while (@cleared < $n) {
+      my ($prime, $fn) = $it->();
+      @seen = uniq sort { $a <=> $b } (@seen, $fn);
+      push @cleared, shift @seen while @seen && $seen[0] < $prime;
+   }
+   return @cleared[0 .. $n - 1];
+}
+
+sub fortunate_numbers_it {
+   my $primorial = 1;
+   my $prime = 1; # bear with me please...
+   return sub {
+      $prime = next_prime($prime);
+      $primorial *= $prime;
+      return (2, 3) if $prime == 2;
+      my $n = $prime;
+      while ('necessary') {
+         $n += 2;
+         return ($prime, $n) if is_prime($primorial + $n);
+      }
+   };
+}
diff --git a/challenge-155/polettix/perl/ch-2.pl b/challenge-155/polettix/perl/ch-2.pl
new file mode 100644
index 0000000000..a52fab6cbd
--- /dev/null
+++ b/challenge-155/polettix/perl/ch-2.pl
@@ -0,0 +1,17 @@
+#!/usr/bin/env perl
+use v5.24;
+use warnings;
+use experimental 'signatures';
+no warnings 'experimental::signatures';
+
+say pisano_period(shift // 3);
+
+sub pisano_period ($n) {
+   my ($fl, $fh) = (0, 1 % $n);
+   my $pp = 0;
+   while ('necessary') {
+      ($fl, $fh) = ($fh, ($fl + $fh) % $n);
+      ++$pp;
+      return $pp if $fl == 0 && $fh == 1 % $n;
+   }
+}
diff --git a/challenge-155/polettix/perl/cpanfile b/challenge-155/polettix/perl/cpanfile
index 91dda9616f..aa20fef593 100644
--- a/challenge-155/polettix/perl/cpanfile
+++ b/challenge-155/polettix/perl/cpanfile
@@ -1 +1,2 @@
 requires 'Math::Prime::Util';
+requires 'List::MoreUtils';
diff --git a/challenge-155/polettix/perl/cpanfile.snapshot b/challenge-155/polettix/perl/cpanfile.snapshot
index 2fd600a3af..4927cf8387 100644
--- a/challenge-155/polettix/perl/cpanfile.snapshot
+++ b/challenge-155/polettix/perl/cpanfile.snapshot
@@ -1,5 +1,36 @@
 # carton snapshot format: version 1.0
 DISTRIBUTIONS
+  Exporter-Tiny-1.002002
+    pathname: T/TO/TOBYINK/Exporter-Tiny-1.002002.tar.gz
+    provides:
+      Exporter::Shiny 1.002002
+      Exporter::Tiny 1.002002
+    requirements:
+      ExtUtils::MakeMaker 6.17
+      perl 5.006001
+  List-MoreUtils-0.430
+    pathname: R/RE/REHSACK/List-MoreUtils-0.430.tar.gz
+    provides:
+      List::MoreUtils 0.430
+      List::MoreUtils::PP 0.430
+    requirements:
+      Exporter::Tiny 0.038
+      ExtUtils::MakeMaker 0
+      List::MoreUtils::XS 0.430
+  List-MoreUtils-XS-0.430
+    pathname: R/RE/REHSACK/List-MoreUtils-XS-0.430.tar.gz
+    provides:
+      List::MoreUtils::XS 0.430
+    requirements:
+      Carp 0
+      ExtUtils::MakeMaker 0
+      File::Basename 0
+      File::Copy 0
+      File::Path 0
+      File::Spec 0
+      IPC::Cmd 0
+      XSLoader 0.22
+      base 0
   Math-Prime-Util-0.73
     pathname: D/DA/DANAJ/Math-Prime-Util-0.73.tar.gz
     provides:
diff --git a/challenge-155/polettix/raku/ch-1.raku b/challenge-155/polettix/raku/ch-1.raku
new file mode 100644
index 0000000000..5c6d5bb3fd
--- /dev/null
+++ b/challenge-155/polettix/raku/ch-1.raku
@@ -0,0 +1,45 @@
+#!/usr/bin/env raku
+
+sub MAIN (Int:D $n = 8) {
+   first-fortunate-numbers($n).join(', ').put;
+   return 0;
+}
+
+sub first-fortunate-numbers($n) {
+   my &it = fortunate-numbers-it();
+   my @cleared;
+   my @seen;
+   while @cleared < $n {
+      my ($prime, $fn) = &it();
+      @seen = (@seen.Slip, $fn).sort.unique;
+      @cleared.push: @seen.shift while @seen && @seen[0] < $prime;
+   }
+   return @cleared[^$n];
+}
+
+sub fortunate-numbers-it() {
+   my $primorial = 1;
+   my &pit = primes-it();
+   return sub {
+      my $prime = &pit();    # get next prime
+      $primorial *= $prime;  # update the primorial
+      return 2, 3 if $prime == 2;
+      my $n = $prime;
+      loop {
+         $n += 2;
+         return $prime, $n if ($primorial + $n).is-prime;
+      }
+   }
+}
+
+sub primes-it() {
+   my @cache = 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47;
+   my $last;
+   return sub {
+      return $last = @cache.shift if @cache;
+      loop {
+         $last += 2;
+         return $last if $last.is-prime;
+      }
+   }
+}
diff --git a/challenge-155/polettix/raku/ch-2.raku b/challenge-155/polettix/raku/ch-2.raku
new file mode 100644
index 0000000000..0c9d8b4565
--- /dev/null
+++ b/challenge-155/polettix/raku/ch-2.raku
@@ -0,0 +1,15 @@
+#!/usr/bin/env raku
+use v6;
+
+sub MAIN (Int:D $n = 3) { put pisano-period($n) }
+
+multi sub pisano-period (1)  { return 1 }
+multi sub pisano-period ($n) {
+   my ($fl, $fh) = 0, 1;
+   my $pp = 0;
+   loop {
+      ($fl, $fh) = $fh, ($fl + $fh) % $n;
+      ++$pp;
+      return $pp if $fl == 0 && $fh == 1;
+   }
+}