A-M baby

Task/Matrix-transposition/ACL2/matrix-transposition.acl2

@@ -0,0 +1,17 @@
+(defun cons-each (xs xss)
+   (if (or (endp xs) (endp xss))
+       nil
+       (cons (cons (first xs) (first xss))
+             (cons-each (rest xs) (rest xss)))))
+
+(defun list-each (xs)
+   (if (endp xs)
+       nil
+       (cons (list (first xs))
+             (list-each (rest xs)))))
+
+(defun transpose-list (xss)
+   (if (endp (rest xss))
+       (list-each (first xss))
+       (cons-each (first xss)
+                  (transpose-list (rest xss)))))