diff --git a/a3/binary_search_tree.c b/a3/binary_search_tree.c
index f95c12c..87eab08 100644
--- a/a3/binary_search_tree.c
+++ b/a3/binary_search_tree.c
@@ -5,7 +5,7 @@
 
 void free_tree(node_t *tree) {
     if (tree == NULL) {
-        return 0;
+        return;
     }
 
     free_tree(tree->left);