This presentations gives an introduction to the data structure linked-lists. I discuss the implementation of header-based linked-lists in C. The presentation runs through the code and provides the visualization of the code w.r.t pointers.

1. Linked Lists CH Gowri Kumar [email_address]

2. struct node { int data; struct node* next; }; typedef struct node Node; typedef struct node* List; List Initialize(); void InsertBegin(List l,int d); void InsertEnd(List l, int d); void Insert(List l, Node* pos,int d); Node* Find(List l,int d); void Delete(List l, int d);

4. Initialize

5. List Initialize() { Node* temp; temp = (Node*)calloc(1,sizeof(Node)); return temp; }

6. List Initialize() { Node* temp; temp = (Node*)calloc(1,sizeof(Node)); return temp; } main() { List head; head = Initialize(); } X head

7. InsertBegin

8. X head 1 10 8 4 6 3 2 5

9. X head 1 10 8 4 6 3 2 5 void InsertBegin(List head,int d) { Node* temp; temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; temp->next = head->next; head->next = temp; }

10. X head 1 10 8 4 6 3 2 5 void InsertBegin(List head,int d) { Node* temp; temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; temp->next = head->next; head->next = temp; } 1

11. X head 1 10 8 4 6 3 2 5 1

12. 1 10 8 4 6 3 2 5 void InsertBegin(List head,int d) { Node* temp; temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; temp->next = head->next; head->next = temp; } X head 1

13. 1 10 8 4 6 3 2 5 void InsertBegin(List head,int d) { Node* temp; temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; temp->next = head->next; head->next = temp; } X head 1

14. 1 10 8 4 6 3 2 5 void InsertBegin(List head,int d) { Node* temp; temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; head->next = temp; temp->next = head->next; } X head 1

15. X head 1 10 8 4 6 3 2 5 void InsertBegin(List head,int d) { Node* temp; temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; temp->next = head->next; head->next = temp; } 1

16. X head 1 10 8 4 6 3 2 5 void InsertBegin(List head,int d) { Node* temp; temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; temp->next = head->next; head->next = temp; } 1 10

17. X head 1 10 8 4 6 3 2 5 void InsertBegin(List head,int d) { Node* temp; temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; head->next = temp; temp->next = head->next; } 1 10

18. InsertEnd

19. X head 1 10 8 4 6 3 2 5 void InsertEnd(List head,int d) { Node *tail,*temp; tail = head; . . . . . . . . . . . . . . . . } 10 1 tail

20. 1 10 8 4 6 3 2 5 void InsertEnd(List head,int d) { Node *tail,*temp; tail = head; while(tail->next != NULL) tail = tail->next; . . . . . . . . . . . . . . . . } X head 10 1 tail

21. 1 10 8 4 6 3 2 5 void InsertEnd(List head,int d) { Node *tail,*temp; tail = head; while(tail->next != NULL) tail = tail->next; . . . . . . . . . . . . . . . . } X head 10 1 tail

22. X head 1 10 8 4 6 3 2 5 void InsertEnd(List head,int d) { . . . . . . . . . . . . . . . . temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; tail->next = temp; } 10 1 8 tail

23. Insert

24. X head 1 10 8 4 6 3 2 5 void Insert(List head,Node* p,int d) { temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; temp->next = p->next; p->next = temp; } 10 1 8

25. X head 1 10 8 4 6 3 2 5 void Insert(List head,Node* p,int d) { temp = (Node*)calloc(1,sizeof(Node)); temp->data = d; temp->next = p->next; p->next = temp; } 10 1 8 4

26. X head 1 10 8 4 6 3 2 5 8 10 1 4

27. Find

28. X head 1 10 8 4 6 3 2 5 8 void Find(List l,Node* p,int d) { Node *temp; temp = l; while(temp->next != NULL) { if(temp->next->data == d) return temp; temp = temp->next; } return NULL; } 10 1 4

29. X head 1 10 8 4 6 3 2 5 8 void Find(List l,Node* p,int d) { Node *temp; temp = l; while(temp->next != NULL) { if(temp->next->data == d) return temp; temp = temp->next; } return NULL; } 10 1 4 temp

30. Delete

31. X head 1 10 8 4 6 3 2 5 8 void Delete(List l,Node* p,int d) { Node *temp,*del; temp = Find(l,d); if(temp != NULL) { del = temp->next; temp->next = del->next; free(del); } } 10 4 1

32. X head 1 10 8 4 6 3 2 5 8 void Delete(List l,Node* p,int d) { Node *temp,*del; temp = Find(l,d); if(temp != NULL) { del = temp->next; temp->next = del->next; free(del); } } 10 4 1 temp del

33. X head 10 8 4 6 3 2 5 10 4 8

34. int main { List l; Node* temp; l = Initialize(); InsertBegin(l,1); InsertBegin(l,10); InsertEnd(l,8); temp = Find(l,8); Insert(l,temp,4); Delete(l,1); }

35. The End