diff --git a/cv4/list_ops.c b/cv4/list_ops.c
index b040c63..8c1098d 100644
--- a/cv4/list_ops.c
+++ b/cv4/list_ops.c
@@ -4,15 +4,21 @@
 list_t *new_list(size_t length, list_element_t elements[]){
 	list_t* list = (list_t*)malloc(sizeof(list_t) + length * sizeof(list_element_t));
 	list->length = length;
+	//list->elements = list + sizeof(list_t);
 	memcpy(list->elements,elements, length*sizeof(list_element_t));
 	return list;
 }
 
 // append entries to a list and return the new list
 list_t *append_list(list_t *list1, list_t *list2){
-	if(list1==list2){};
-  return NULL;
+//	list3.lenght=list1->lenght+list2->lenght;
+	list_t* list3 = (list_t*)malloc(sizeof(list_t) + (list1->length+list2->length) * sizeof(list_element_t));
+        list3->length = list1->length+list2->length;
+        //list->elements = list + sizeof(list_t);
+        memcpy(list3->elements,list1->elements, list1->length*sizeof(list_element_t));
+	memcpy(list3->elements+list1->length*sizeof(list_element_t),list2->elements, list2->length*sizeof(list_element_t));
 
+        return list3;
 }
 
 // filter list returning only values that satisfy the filter function