Add polettix's solution to challenge-153

6 files changed, 86 insertions, 0 deletions

diff --git a/challenge-153/polettix/blog.txt b/challenge-153/polettix/blog.txt
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+++ b/challenge-153/polettix/blog.txt
@@ -0,0 +1 @@
+https://github.polettix.it/ETOOBUSY/2022/02/23/pwc153-left-factorials/
diff --git a/challenge-153/polettix/blog1.txt b/challenge-153/polettix/blog1.txt
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index 0000000000..4c6eecf03d
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+++ b/challenge-153/polettix/blog1.txt
@@ -0,0 +1 @@
+https://github.polettix.it/ETOOBUSY/2022/02/24/pwc153-factorions/
diff --git a/challenge-153/polettix/perl/ch-1.pl b/challenge-153/polettix/perl/ch-1.pl
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+++ b/challenge-153/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';
+use Memoize;
+
+my $min = shift // 1;
+my $max = shift // 10;
+say join ', ', map { left_factorial($_) } $min .. $max;
+
+memoize('left_factorial');
+sub left_factorial ($n) {
+   return $n if $n <= 2;
+   return factorial($n - 1) + left_factorial($n - 1);
+}
+
+memoize('factorial');
+sub factorial ($n) {
+   return 1 if $n < 2;
+   return $n * factorial($n - 1);
+}
diff --git a/challenge-153/polettix/perl/ch-2.pl b/challenge-153/polettix/perl/ch-2.pl
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index 0000000000..ccb4269116
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+++ b/challenge-153/polettix/perl/ch-2.pl
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+#!/usr/bin/env perl
+use v5.24;
+use warnings;
+use experimental 'signatures';
+no warnings 'experimental::signatures';
+use List::Util 'sum';
+
+say is_factorion(shift // 145) ? 1 : 0;
+
+sub is_factorion ($n) {
+   state $f = [ 1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880 ];
+   $n == sum map { $f->[$_] } split m{}mxs, $n;
+}
+
+
+my $s = '';
+while ('necessary') {
+   $s .= '9';
+   last if $s > sumfact($s);
+}
+my $max = sumfact($s);
+say $s, ' ', $max;
+
+for my $n (0 .. $max) {
+   say $n if is_factorion($n);
+}
+
+sub sumfact ($n) {
+   state $f = [ 1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880 ];
+   sum map { $f->[$_] } split m{}mxs, $n;
+}
diff --git a/challenge-153/polettix/raku/ch-1.raku b/challenge-153/polettix/raku/ch-1.raku
new file mode 100644
index 0000000000..d216784869
--- /dev/null
+++ b/challenge-153/polettix/raku/ch-1.raku
@@ -0,0 +1,23 @@
+#!/usr/bin/env raku
+use v6;
+sub MAIN (Int:D $min = 1, Int:D $max = 10) {
+   ($min .. $max).map({left-factorial($_)}).join(', ').put;
+   ($min .. $max).map({left-factorial-cached($_)}).join(', ').put;
+}
+
+multi sub left-factorial (Int:D $n where 0 <= * <= 2) { $n }
+multi sub left-factorial (Int:D $n where * >  2) {
+   my $f = 1;
+   1 + (1 ..^ $n).map({$f *= $^x}).sum;
+}
+
+sub left-factorial-cached (Int:D $n where * >= 0) {
+   state $factorial = 1;
+   state $k = 1;
+   state @left-factorials = 0, 1, 2;
+   while $n > @left-factorials.end {
+      $factorial *= ++$k;
+      @left-factorials.push: @left-factorials[*-1] + $factorial;
+   }
+   return @left-factorials[$n];
+}
diff --git a/challenge-153/polettix/raku/ch-2.raku b/challenge-153/polettix/raku/ch-2.raku
new file mode 100644
index 0000000000..79791344b6
--- /dev/null
+++ b/challenge-153/polettix/raku/ch-2.raku
@@ -0,0 +1,8 @@
+#!/usr/bin/env raku
+use v6;
+sub MAIN (Int:D $n = 145) { put is-factorion($n) ?? 1 !! 0 }
+
+sub is-factorion (Int:D $n where $n >= 0) {
+   state %factorions = set(1, 2, 145, 40585);
+   return $n ∈ %factorions;
+}