From af1ebf1ddb1ffed1f0f10aca8c31d79ba28f3421 Mon Sep 17 00:00:00 2001
From: Joelle Maslak <jmaslak@antelope.net>
Date: Mon, 17 Jun 2019 11:06:54 -0700
Subject: Solution for 13.2 in P5 & P6

---
 challenge-013/joelle-maslak/perl5/ch-2.pl | 37 +++++++++++++++++++++++++++++++
 challenge-013/joelle-maslak/perl6/ch-2.p6 | 21 ++++++++++++++++++
 2 files changed, 58 insertions(+)
 create mode 100755 challenge-013/joelle-maslak/perl5/ch-2.pl
 create mode 100755 challenge-013/joelle-maslak/perl6/ch-2.p6

diff --git a/challenge-013/joelle-maslak/perl5/ch-2.pl b/challenge-013/joelle-maslak/perl5/ch-2.pl
new file mode 100755
index 0000000000..92e9ba379d
--- /dev/null
+++ b/challenge-013/joelle-maslak/perl5/ch-2.pl
@@ -0,0 +1,37 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+
+use v5.22;
+
+# Turn on method signatures
+use feature 'signatures';
+no warnings 'experimental::signatures';
+
+# If you try computing say 1000 of these, you get a mess without
+# caching.  It gives deep recursion warnings and slowness.  So we use
+# Memoize to speed this up.
+use Memoize;
+
+memoize('F');
+sub F($n) {
+    return 1 if $n == 0;
+    return $n - M( F($n-1) );
+}
+
+memoize('M');
+sub M($n) {
+    return 0 if $n == 0;
+    return $n - F( M($n-1) );
+}
+
+die("Must provide number of elements") if @ARGV != 1;
+my $len = +$ARGV[0];
+
+my @f = map { F($_) } (0..($len-1));
+my @m = map { M($_) } (0..($len-1));
+
+say "F: " . join(" ", @f);
+say "M: " . join(" ", @m);
+
diff --git a/challenge-013/joelle-maslak/perl6/ch-2.p6 b/challenge-013/joelle-maslak/perl6/ch-2.p6
new file mode 100755
index 0000000000..da9c25c506
--- /dev/null
+++ b/challenge-013/joelle-maslak/perl6/ch-2.p6
@@ -0,0 +1,21 @@
+#!/usr/bin/env perl6
+use v6;
+
+use experimental :cached;
+
+sub MAIN(UInt:D $length) {
+    my @f = lazy (0..∞).map: { F($_) };
+    my @m = lazy (0..∞).map: { M($_) };
+
+    say "F: { @f[^$length] }";
+    say "M: { @m[^$length] }";
+}
+
+multi sub F(0) { 1 }
+multi sub M(0) { 0 }
+
+# We cache these results, but can't use the cached trait (because it's a
+# multi?), so we do it the old-fashioned way.
+multi sub F($n where * > 0 ) { state %c; %c{$n} //= $n - M( F($n-1) ) }
+multi sub M($n where * > 0 ) { state %c; %c{$n} //= $n - F( M($n-1) ) }
+
-- 
cgit