it doesnt get any faster =(

1 files changed, 20 insertions, 11 deletions

diff --git a/challenge-054/markus-holzer/raku/ch-2.p6 b/challenge-054/markus-holzer/raku/ch-2.p6
index bd4d4c2924..ec33d32087 100644
--- a/challenge-054/markus-holzer/raku/ch-2.p6
+++ b/challenge-054/markus-holzer/raku/ch-2.p6
@@ -1,34 +1,43 @@
-sub MAIN( Int $N )
+multi sub MAIN( Int $N, :$l )
 {
     my $start  = now;
-    my %result = 1 => 1;
+    my @result = Array.new( Any, 1, :shape( $N + 1 ) );
 
     for 1..$N -> $n
     {
         my $current = 0;
         my $next    = $n;
-
+        my $cached;
         loop
         {
             # Dynamic programming:
             # see what you have computed so far, so you
             # don't have to compute it again
-            %result{ $n } = %result{ $next } and last
-                if %result{ $next };
+            $cached = @result[ $next ];
+            last if $cached;
 
             $next = $next %% 2 ?? $next / 2 !! $next * 3 + 1;
             $current++;
         }
 
-        %result{ $n } += $current;
+        @result[ $n ] = [ $n, $current + $cached ];
     }
 
-    say "n: $_, length: %result{ $_ }" for
-        %result
-            .keys
-            .sort({ %result{ $^b } <=> %result{ $^a } })
-            .head( 20 );
+    say "n: { .[0] }, length: { .[1] }" for
+        @result
+            .skip
+            .sort( -*[1] )
+            .head(20);
 
     say "runtime: { now - $start } seconds";
 }
 
+multi sub MAIN( Int $n, :$s )
+{
+    say collatz( $n ).join( ',' );
+}
+
+sub collatz( Int $n )
+{
+    $n, { $^n %% 2 ?? $^n / 2 !! $^n * 3 + 1 } ... { $^n == 1 }
+}