Data commit

Task/Knuth-shuffle/ACL2/knuth-shuffle.acl2

@@ -0,0 +1,24 @@
+:set-state-ok t
+
+(defun array-swap (name array i j)
+   (let ((ai (aref1 name array i))
+         (aj (aref1 name array j)))
+      (aset1 name
+             (aset1 name array j ai)
+             i aj)))
+
+(defun shuffle-r (name array m state)
+   (if (zp m)
+       (mv array state)
+       (mv-let (i state)
+               (random$ m state)
+          (shuffle-r name
+                     (array-swap name array i m)
+                     (1- m)
+                     state))))
+
+(defun shuffle (name array state)
+   (shuffle-r name
+              array
+              (1- (first (dimensions name array)))
+              state))