juliodcs-week86

1 files changed, 4 insertions, 8 deletions

diff --git a/challenge-086/juliodcs/raku/ch-2.raku b/challenge-086/juliodcs/raku/ch-2.raku
index ef6d7e99c7..194eab6a9e 100644
--- a/challenge-086/juliodcs/raku/ch-2.raku
+++ b/challenge-086/juliodcs/raku/ch-2.raku
@@ -65,17 +65,13 @@ sub get-guesses(@sudoku, $y, $x, $last-guess) {
     my @square := get-square @sudoku, $y, $x;

     my @all-nums := (@cross-y, @cross-x, @square).flat.sort.unique.list;

 

-    # This 2 things puzzled me:

-    # 1)

-    #     `grep(-> $guess { 0 == elems @all-nums.grep: * == $guess })`

-    #     is almost twice as fast as:

-    #     `grep({ $_ == none @all-nums })`

-    #

-    # 2) Using `grep(* > $last-guess)` as the first grep, is VERY slow

+    # Using `grep(-> $guess { 0 == elems @all-nums.grep: * == $guess })`

+    # instead of `grep({ $_ == none @all-nums })`

+    # because first is twice as fast

     

     eager (1 .. 9)

         ==> grep(-> $guess { 0 == elems @all-nums.grep: * == $guess })

-        ==> grep(* > $last-guess)

+        ==> grep * > $last-guess

 }

 

 # For a (y,x) pair, it returns all the boxes of its inner square