initial commit on 054,055

6 files changed, 91 insertions, 0 deletions

diff --git a/challenge-054/stuart-little/README b/challenge-054/stuart-little/README
new file mode 100644
index 0000000000..78439907de
--- /dev/null
+++ b/challenge-054/stuart-little/README
@@ -0,0 +1 @@
+Solutions by Stuart Little
diff --git a/challenge-054/stuart-little/raku/ch-1.p6 b/challenge-054/stuart-little/raku/ch-1.p6
new file mode 100755
index 0000000000..3530a98037
--- /dev/null
+++ b/challenge-054/stuart-little/raku/ch-1.p6
@@ -0,0 +1,21 @@
+#!/usr/bin/env perl6
+use v6;
+
+sub rk_perm(@a, $k) {
+    given my ($ix,$fact) = ((1..@a.elems) Z [\*](1..@a.elems)).first({ $_[1] < $k }, :end) {
+	when ! *.[0].defined { @a }
+	when *.[0] == @a.elems { @a.reverse }
+	when *.[0] < @a.elems-1 {
+	    (|@a[^(@a.elems-$ix-1)], |rk_perm(@a[(@a.elems-$ix-1)..*], $k))
+	}
+	default {
+	    my $init_ix=ceiling($k/$fact)-1;
+	    my @rest=(@a.keys (-) $init_ix).keys.sort;
+	    (@a[$init_ix], |rk_perm(@a[@rest], $k-($fact * (ceiling($k/$fact)-1))))
+	}
+    }
+}
+
+say rk_perm((1..@*ARGS[0].Int).List, (@*ARGS[1] || 1).Int);
+
+# run as <script> <$n for which we're permuting 1..$n> <the rank $k of the permutation you want> 
diff --git a/challenge-054/stuart-little/raku/ch-2.p6 b/challenge-054/stuart-little/raku/ch-2.p6
new file mode 100755
index 0000000000..7c71620fc1
--- /dev/null
+++ b/challenge-054/stuart-little/raku/ch-2.p6
@@ -0,0 +1,45 @@
+#!/usr/bin/env perl6
+use v6;
+
+my %*SUB-MAIN-OPTS=:named-anywhere,;
+my %cllens = (1 => 1);
+
+sub cltz($n) { ($n %% 2) ?? ($n div 2) !! (($n > 1) ?? (3*$n+1) !! (1)) }
+
+sub cllen($n) {
+    %cllens{$n} //= 1+cllen($n.&cltz)
+}
+
+sub cltz_seq(Int $n where * > 0) {
+    given $n {
+	when 1 { (1,) }
+	when * %% 2 { ($n,|cltz_seq($n div 2)) }
+	default { ($n,|cltz_seq(3*$n+1)) }
+    }
+}
+
+multi sub MAIN(
+    Bool :b(:$bonus),
+) {
+    my $L=1_000_000;
+    my $wndw=20;
+    my @maxn=[1];
+
+    for (1..$L) {
+	my $ln = cllen($_);
+	($ln > %cllens{@maxn}.max) && do {
+	    (@maxn.elems == $wndw) && @maxn.shift;
+	    @maxn.push($_)
+	}	
+    }
+
+    for @maxn {
+	say $_ ~ " " ~ %cllens{$_}
+    }
+}
+
+multi sub MAIN(
+    *@ARGS,
+) {
+    say @ARGS[0].Int.&cltz_seq;
+}
diff --git a/challenge-055/stuart-little/README b/challenge-055/stuart-little/README
new file mode 100644
index 0000000000..78439907de
--- /dev/null
+++ b/challenge-055/stuart-little/README
@@ -0,0 +1 @@
+Solutions by Stuart Little
diff --git a/challenge-055/stuart-little/raku/ch-1.p6 b/challenge-055/stuart-little/raku/ch-1.p6
new file mode 100755
index 0000000000..bd77d55d9e
--- /dev/null
+++ b/challenge-055/stuart-little/raku/ch-1.p6
@@ -0,0 +1,10 @@
+#!/usr/bin/env perl6
+use v6;
+
+sub max1flip(Str $s where * ~~ /^(0|1)*$/) {
+    ((^$s.chars) X (^$s.chars)).grep({ $_[0] <= $_[1] }).classify({ $s.substr($_[0]..$_[1]).comb.grep(0).elems - $s.substr($_[0]..$_[1]).comb.grep(1).elems }).max(*.key).value
+}
+
+say @*ARGS[0].&max1flip
+
+# run as <script> <binary string> 
diff --git a/challenge-055/stuart-little/raku/ch-2.p6 b/challenge-055/stuart-little/raku/ch-2.p6
new file mode 100755
index 0000000000..49aece53ba
--- /dev/null
+++ b/challenge-055/stuart-little/raku/ch-2.p6
@@ -0,0 +1,13 @@
+#!/usr/bin/env perl6
+use v6;
+
+sub wv(@a,$b) {
+    $b eqv ().Bag && do {say @a; return};
+    for $b.keys.grep({ (@a %% 2) ?? ($_ >= (@a[*-1] || -Inf)) !! ($_ <= (@a[*-1] || Inf)) }) {
+	wv((|@a,$_),($b (-) $_))
+    }
+}
+
+wv((), @*ARGS.map(*.Int).Bag)
+
+# run as <script> <space-separated integers>