Merge branch 'master' of https://github.com/manwar/perlweeklychallenge-club

9 files changed, 78 insertions, 40 deletions

diff --git a/challenge-150/polettix/raku/ch-2.raku b/challenge-150/polettix/raku/ch-2.raku
index 35a29749b0..a7f858a3e1 100644
--- a/challenge-150/polettix/raku/ch-2.raku
+++ b/challenge-150/polettix/raku/ch-2.raku
@@ -18,7 +18,7 @@ sub is-square-free ($N is copy) {
    return False if $N %% 4;
    my $divisor = 3;
    while $N > $divisor {
-      if $N %% $divisor == 0 {
+      if $N %% $divisor {
          $N = ($N / $divisor).Int;
          return False if $N %% $divisor;
       }
diff --git a/challenge-159/polettix/blog.txt b/challenge-159/polettix/blog.txt
new file mode 100644
index 0000000000..a7d0f36761
--- /dev/null
+++ b/challenge-159/polettix/blog.txt
@@ -0,0 +1 @@
+https://github.polettix.it/ETOOBUSY/2022/04/05/pwc159-farey-sequence/
diff --git a/challenge-159/polettix/blog1.txt b/challenge-159/polettix/blog1.txt
new file mode 100644
index 0000000000..98e41e86c3
--- /dev/null
+++ b/challenge-159/polettix/blog1.txt
@@ -0,0 +1 @@
+https://github.polettix.it/ETOOBUSY/2022/04/06/pwc159-moebius-number/
diff --git a/challenge-159/polettix/perl/ch-1.pl b/challenge-159/polettix/perl/ch-1.pl
new file mode 100644
index 0000000000..960834ecd9
--- /dev/null
+++ b/challenge-159/polettix/perl/ch-1.pl
@@ -0,0 +1,19 @@
+#!/usr/bin/env perl
+use v5.24;
+use warnings;
+use experimental 'signatures';
+no warnings 'experimental::signatures';
+
+say join ', ', farey_sequence(shift || 4);
+
+sub farey_sequence ($n) {
+   my @retval;
+   my @cache = (0, 1, 1, $n);
+   while ($cache[2] < $n) {
+      my $k = int(($n + $cache[1]) / $cache[3]);
+      push @cache, $k * $cache[2] - $cache[0], $k * $cache[3] - $cache[1];
+      push @retval, join '/', splice @cache, 0, 2;
+   }
+   push @retval, '1/1';
+   return @retval;
+}
diff --git a/challenge-159/polettix/perl/ch-2.pl b/challenge-159/polettix/perl/ch-2.pl
new file mode 100644
index 0000000000..19dea2a0b9
--- /dev/null
+++ b/challenge-159/polettix/perl/ch-2.pl
@@ -0,0 +1,23 @@
+#!/usr/bin/env perl
+use v5.24;
+use warnings;
+use experimental 'signatures';
+no warnings 'experimental::signatures';
+
+say $_, ' ', moebius_number($_) for (@ARGV ? @ARGV : (1 .. 10));
+
+sub moebius_number ($n) {
+   return 0 unless $n % 4;
+   ($n, my $n_divisors) = $n % 2 ? ($n, 0) : ($n / 2, 1);
+   my $divisor = 3;
+   while ($n >= $divisor) {
+      if ($n % $divisor == 0) {
+         ++$n_divisors;
+         $n /= $divisor;
+         return 0 unless $n % $divisor;
+      }
+      $divisor += 2; # go through odd candidates only
+   }
+   return 1 - 2 * ($n_divisors % 2);
+}
+
diff --git a/challenge-159/polettix/perl/cpanfile b/challenge-159/polettix/perl/cpanfile
deleted file mode 100644
index 91dda9616f..0000000000
--- a/challenge-159/polettix/perl/cpanfile
+++ /dev/null
@@ -1 +0,0 @@
-requires 'Math::Prime::Util';
diff --git a/challenge-159/polettix/perl/cpanfile.snapshot b/challenge-159/polettix/perl/cpanfile.snapshot
deleted file mode 100644
index 2fd600a3af..0000000000
--- a/challenge-159/polettix/perl/cpanfile.snapshot
+++ /dev/null
@@ -1,38 +0,0 @@
-# carton snapshot format: version 1.0
-DISTRIBUTIONS
-  Math-Prime-Util-0.73
-    pathname: D/DA/DANAJ/Math-Prime-Util-0.73.tar.gz
-    provides:
-      Math::Prime::Util 0.73
-      Math::Prime::Util::ChaCha 0.73
-      Math::Prime::Util::Entropy 0.73
-      Math::Prime::Util::MemFree 0.73
-      Math::Prime::Util::PP 0.73
-      Math::Prime::Util::PrimeArray 0.73
-      Math::Prime::Util::PrimeIterator 0.73
-      ntheory 0.73
-    requirements:
-      Carp 0
-      Config 0
-      Exporter 5.57
-      ExtUtils::MakeMaker 0
-      Math::BigFloat 1.59
-      Math::BigInt 1.88
-      Math::Prime::Util::GMP 0.50
-      Tie::Array 0
-      XSLoader 0.01
-      base 0
-      constant 0
-      perl 5.006002
-  Math-Prime-Util-GMP-0.52
-    pathname: D/DA/DANAJ/Math-Prime-Util-GMP-0.52.tar.gz
-    provides:
-      Math::Prime::Util::GMP 0.52
-    requirements:
-      Carp 0
-      Exporter 5.57
-      ExtUtils::MakeMaker 0
-      Fcntl 0
-      XSLoader 0.01
-      base 0
-      perl 5.006002
diff --git a/challenge-159/polettix/raku/ch-1.raku b/challenge-159/polettix/raku/ch-1.raku
new file mode 100644
index 0000000000..e2c4ec19af
--- /dev/null
+++ b/challenge-159/polettix/raku/ch-1.raku
@@ -0,0 +1,15 @@
+#!/usr/bin/env raku
+use v6;
+sub MAIN (Int:D \n = 4) { farey-sequence(n).join(', ').put }
+
+sub farey-sequence (Int:D \n) {
+   my ($a, $b, $c, $d) = (0, 1, 1, n);
+   gather {
+      take "$a/$b";
+      while $c <= n {
+         my $k = ((n + $b) / $d).Int;
+         ($a, $b, $c, $d) = $c, $d, $k * $c - $a, $k * $d - $b;
+         take "$a/$b";
+      }
+   }
+}
diff --git a/challenge-159/polettix/raku/ch-2.raku b/challenge-159/polettix/raku/ch-2.raku
new file mode 100644
index 0000000000..fb37765261
--- /dev/null
+++ b/challenge-159/polettix/raku/ch-2.raku
@@ -0,0 +1,18 @@
+#!/usr/bin/env raku
+use v6;
+multi sub MAIN (*@args) { put $_, ' ', möbius-number($_) for @args}
+
+sub möbius-number ($n is copy) {
+   return 0 if $n %% 4;
+   ($n, my $n-divisors) = $n %% 2 ?? (($n / 2).Int, 1) !! ($n, 0);
+   my $divisor = 3;
+   while $n >= $divisor {
+      if $n %% $divisor {
+         ++$n-divisors;
+         $n = ($n / $divisor).Int;
+         return 0 if $n %% $divisor;
+      }
+      $divisor += 2; # go through odd candidates only
+   }
+   return 1 - 2 * ($n-divisors % 2);
+}