A-M baby

Task/Knuths-algorithm-S/Common-Lisp/knuths-algorithm-s-1.lisp

@@ -0,0 +1,26 @@
+(defun s-n-creator (n)
+  (let ((sample (make-array n :initial-element nil))
+        (i 0))
+    (lambda (item)
+      (if (<= (incf i) n)
+          (setf (aref sample (1- i)) item)
+        (when (< (random i) n)
+          (setf (aref sample (random n)) item)))
+      sample)))
+
+(defun algorithm-s ()
+  (let ((*random-state* (make-random-state t))
+        (frequency (make-array '(10) :initial-element 0)))
+    (loop repeat 100000
+          for s-of-n = (s-n-creator 3)
+          do (flet ((s-of-n (item)
+                      (funcall s-of-n item)))
+               (map nil
+                    (lambda (i)
+                      (incf (aref frequency i)))
+                    (loop for i from 0 below 9
+                          do (s-of-n i)
+                          finally (return (s-of-n 9))))))
+    frequency))
+
+(princ (algorithm-s))

Task/Knuths-algorithm-S/Common-Lisp/knuths-algorithm-s-2.lisp

@@ -0,0 +1 @@
+#(30026 30023 29754 30017 30267 29997 29932 29990 29965 30029)