() Given the following structure definition: struct node_st \{ char string; struct node_st next; \}; Write a C function, stir_list(), that takes a pointer to a NULL-terminated linked list (possibly empty) made up of these structures containing strings. It makes a new list of anagrams of the given strings. (The anagrams can be created using strfry(), defined in problem 39.) Stir_list() returns a pointer to the head of the new list. The original list of strings should be left unchanged. Write robust code. struct node_st stir_list(struct node_st list) \{