diff --git a/cv4/list_ops.c b/cv4/list_ops.c
index 0fb3e9c..4cbbc3c 100644
--- a/cv4/list_ops.c
+++ b/cv4/list_ops.c
@@ -7,7 +7,7 @@
 list_t *new_list(size_t length, list_element_t elements[]) {
     list_t *list = malloc(sizeof(list_t) + length * sizeof(list_element_t));
     list->length = length;
-    if (list == NULL) {
+    if (!list) {
         return NULL; 
     }
     for (size_t i = 0; i < length; i++) {
@@ -18,7 +18,7 @@ list_t *new_list(size_t length, list_element_t elements[]) {
 
 list_t *append_list(list_t *list1, list_t *list2) {
     list_t *list3 = malloc(sizeof(list_t) + (list1->length + list2->length) * sizeof(list_element_t));
-     if (list3 == NULL) {
+     if (!list3) {
         return NULL; 
     }
     memcpy(list3,list1,sizeof(list_t));