apl: quicksort recursive partition — Phase 6 classics complete (+9 tests, 315/315)

2026-05-07 06:23:03 +00:00
parent e37167a58e
commit 0f13052900
6 changed files with 98 additions and 7 deletions
--- a/lib/apl/runtime.sx
+++ b/lib/apl/runtime.sx
@@ -907,6 +907,24 @@
    (n)
    (apl-scalar (len (filter apl-queens-valid? (apl-permutations n))))))

+(define
+  apl-quicksort
+  (fn
+    (arr)
+    (let
+      ((ravel (get arr :ravel)))
+      (if
+        (<= (len ravel) 1)
+        arr
+        (let
+          ((pivot (apl-scalar (first ravel))))
+          (let
+            ((less (apl-quicksort (apl-compress (apl-lt arr pivot) arr)))
+              (eq (apl-compress (apl-eq arr pivot) arr))
+              (greater
+                (apl-quicksort (apl-compress (apl-gt arr pivot) arr))))
+            (apl-catenate less (apl-catenate eq greater))))))))
+
 (define
  apl-reduce
  (fn