10: char name[20];
11: struct data *next;
12: };
13:
14: /* Define typedefs for the structure */
15: /* and a pointer to it. */
16: typedef struct data PERSON;
17: typedef PERSON *LINK;
18:
19: int main( void )
20: {
21: /* Head, new, and current element pointers. */
22: LINK head = NULL;
23: LINK new = NULL;
24: LINK current = NULL;
25:
26: /* Add the first list element. We do not */
27: /* assume the list is empty, although in */
28: /* this demo program it always will be. */
29:
30: new = (LINK)malloc(sizeof(PERSON));
31: new->next = head;
32: head = new;
33: strcpy(new->name, “Abigail”);
34:
35: /* Add an element to the end of the list. */
36: /* We assume the list contains at least one element. */
37:
38: current = head;
39: while (current->next != NULL)
40: {
41: current = current->next;
42: }
43:
44: new = (LINK)malloc(sizeof(PERSON));
45: current->next = new;
46: new->next = NULL;
47: strcpy(new->name, “Carolyn”);
48:
49: /* Add a new element at the second position in the list. */
50: new = (LINK)malloc(sizeof(PERSON));
51: new->next = head->next;
52: head->next = new;
53: strcpy(new->name, “Beatrice”);
54:
55: /* Print all data items in order. */
56: current = head;
57: while (current != NULL)
58: {424 Day 15LISTING15.12 continued25 448201x-CH15 8/13/02 11:13 AM Page 424