Add polettix's solution to challenge-173

6 files changed, 69 insertions, 0 deletions

diff --git a/challenge-173/polettix/blog.txt b/challenge-173/polettix/blog.txt
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+++ b/challenge-173/polettix/blog.txt
@@ -0,0 +1 @@
+https://etoobusy.polettix.it/2022/07/13/pwc173-esthetic-number/
diff --git a/challenge-173/polettix/blog1.txt b/challenge-173/polettix/blog1.txt
new file mode 100644
index 0000000000..efc7719be3
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+++ b/challenge-173/polettix/blog1.txt
@@ -0,0 +1 @@
+https://etoobusy.polettix.it/2022/07/14/pwc173-sylvester-s-sequence/
diff --git a/challenge-173/polettix/perl/ch-1.pl b/challenge-173/polettix/perl/ch-1.pl
new file mode 100644
index 0000000000..df7531387f
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+++ b/challenge-173/polettix/perl/ch-1.pl
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+#!/usr/bin/env perl
+use v5.24;
+use warnings;
+use experimental 'signatures';
+no warnings 'experimental::signatures';
+
+say is_esthetic($_) ? "$_ is esthetic" : "$_ is NOT esthetic"
+   for @ARGV;
+
+sub is_esthetic ($candidate) {
+   test_adjacents(
+      sub ($x, $y) { use integer; abs($x - $y) == 1 },
+      split m{}mxs, $candidate
+   );
+}
+
+sub test_adjacents ($test, @input) {
+   for my $i (1 .. $#input) {
+      return 0 unless $test->(@input[$i - 1, $i]);
+   }
+   return 1;
+}
diff --git a/challenge-173/polettix/perl/ch-2.pl b/challenge-173/polettix/perl/ch-2.pl
new file mode 100644
index 0000000000..d61aa0abaa
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+++ b/challenge-173/polettix/perl/ch-2.pl
@@ -0,0 +1,14 @@
+#!/usr/bin/env perl
+use v5.24;
+use warnings;
+use experimental 'signatures';
+no warnings 'experimental::signatures';
+use Math::BigInt;
+
+my $it = sylvester_sequence_it();
+say $it->() for 1 .. shift // 10;
+
+sub sylvester_sequence_it {
+   my $n;
+   return sub { $n = $n ? 1 + $n * ($n - 1) : Math::BigInt->new(2) }
+}
diff --git a/challenge-173/polettix/raku/ch-1.raku b/challenge-173/polettix/raku/ch-1.raku
new file mode 100644
index 0000000000..b3b01dad9b
--- /dev/null
+++ b/challenge-173/polettix/raku/ch-1.raku
@@ -0,0 +1,18 @@
+#!/usr/bin/env raku
+use v6;
+sub MAIN (*@candidates) {
+   put is-esthetic($_) ?? "$_ is esthetic" !! "$_ is NOT esthetic"
+      for @candidates;
+   return 0;
+}
+
+sub is-esthetic ($candidate) {
+   test-adjacents(-> $x, $y { abs($x - $y) == 1 }, $candidate.comb());
+}
+
+sub test-adjacents (&test, *@input) {
+   for 1 ..^ @input -> $i {
+      return False unless &test(|@input[$i - 1, $i]);
+   }
+   return True;
+}
diff --git a/challenge-173/polettix/raku/ch-2.raku b/challenge-173/polettix/raku/ch-2.raku
new file mode 100644
index 0000000000..dde13582e7
--- /dev/null
+++ b/challenge-173/polettix/raku/ch-2.raku
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+#!/usr/bin/env raku
+use v6;
+
+class sylvester-sequence { ... };
+sub MAIN (Int:D $count = 10) {
+   my $ssq = sylvester-sequence.new();
+   put $ssq.next for 1 .. $count;
+}
+
+class sylvester-sequence {
+   has $!n;
+   method next { $!n = $!n ?? 1 + $!n * ($!n - 1) !! 2 }
+}