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2013-04-11 01:07:29 -07:00 · 2013-04-11 01:07:29 -07:00 · 68f8f3e56b
commit 68f8f3e56b
parent b83f433714
14735 changed files with 178959 additions and 0 deletions
--- a/Task/Sorting-algorithms-Bead-sort/Racket/sorting-algorithms-bead-sort.rkt
+++ b/Task/Sorting-algorithms-Bead-sort/Racket/sorting-algorithms-bead-sort.rkt
@ -0,0 +1,15 @@
+#lang racket
+(require rackunit)
+
+(define (columns lst)
+  (match (filter (λ (l) (not (empty? l))) lst)
+    ['() '()]
+    [l (cons (map car l) (columns (map cdr l)))]))
+
+(define (bead-sort lst)
+  (map length (columns (columns (map (λ (n) (make-list n 1)) lst)))))
+
+;; unit test
+(check-equal?
+ (bead-sort '(5 3 1 7 4 1 1))
+ '(7 5 4 3 1 1 1))