- Linked list
list_t *new_list() - create a new list
int clear_list(list_t *list) - remove all items from list
int print_list(list_t *list) - printing all items one by one
int add_item(list_t *list, int value) - add item to the end
int pop_item(list_t *list, int index) - remove item from list by index
int pop_last_item(list_t *list) - remove last item
int get_item(list_t *list, int index) - return item value
int insert_item(list_t *list, int index, int value) - insert item in the middle or front of the list