1 files changed, 2 insertions, 0 deletions
diff --git a/L-99.lisp b/L-99.lisp
index 3c8dc71..b1854fc 100644
--- a/L-99.lisp
+++ b/L-99.lisp
@@ -1,3 +1,5 @@
+(in-package "ACL2")
+
 ;; P01 (*) Find the last box of a list.
 (defun my-last (x)
   (declare (xargs :guard (and (true-listp x)