The document describes the structure and operations of a double linked list, detailing the node structure with 'prev' and 'next' connection fields. It outlines operations including creation, insertion (front, back, and middle), deletion (front, back, and middle), and traversal. Example code and procedural steps are provided for each operation, accompanied by contact information for further inquiries.

1. Double Linked List
Adam M.B.

2. DEFINITION


3. Linked list that its node consists of two
connection fields (prev and next).
Double Linked List
Info Field
(Info)
Right Connection Field
(Next)
Left Connection Field
(Prev)

4. Declaration
Kamus:
Type
nama_pointer = ↑Simpul
Simpul = Record
< medan_data : tipedata,
prev, next : nama_pointer >
EndRecord
nama_var_pointer : nama_pointer

5. Example of Declaration
Kamus:
Type
point = ↑Simpul
Simpul = Record
< info : char,
prev, next : point >
EndRecord
awal,akhir : point

6. Operation
• Creation
• Insertion
• Delete
• Traversal
• Searching
• Sorting
• Destroy
Same with
single linked list

7. CREATION


8. Process
Pointer awal and akhir is given nil
value.
awal akhir

9. INSERTION


10. • If list is empty (awal = nil).
Front Insertion
awal akhir
baru 1
akhir  baru
awal  baru
baru↑.info  1
baru↑.next  nil
baru↑.prev  nil
alloc(baru)

11. • If list isn’t empty (awal ≠ nil). For example,
there is list that has two nodes:
Front Insertion (cont’d)
awal
2 3
akhir
baru 1
alloc(baru)
baru↑.info  1
baru↑.prev  nil

12. Front Insertion (cont’d)
2 3
baru 1
baru↑.next  awal
awal↑.prev  baru
awal baru
awal akhir

13. The last result for front insertion if linked list
wasn’t empty:
Front Insertion (cont’d)
2 3
akhir
1
awalbaru

14. • If list is empty (awal = nil)  the
process is same as front
insertion if double linked
list is empty.
Back Insertion

15. • If list isn’t empty (awal ≠ nil). For example,
there is list that has two nodes:
Back Insertion (cont’d)
awal
2 3
akhir
baru 1
alloc(baru)
baru↑.info  1
baru↑.next  nil

16. New node will be inserted after the node that
was refered by akhir.
Back Insertion (cont’d)
baru
awal
2 3
akhir
1
baru↑.prev  akhir
akhir↑.next  baru
akhir baru

17. The last result for back insertion if linked list
wasn’t empty:
Back Insertion (cont’d)
baru
2 3
1
awal akhirawal
2 3
akhir
1

18. • If list is empty (awal = nil)  the
process is same as front
insertion if linked list is
empty.
Middle Insertion

19. • If list isn’t empty (awal ≠ nil).
Middle Insertion (cont’d)
Node 4 will be inserted before 9:
Awal
5 97
Akhir
10
Awal
5 97
Akhir
10
bantu

20. Middle Insertion (cont’d)
baru 4
alloc(baru)
baru↑.info  4
baru↑.next  bantubaru↑.prev  bantu↑.prev
Awal
5 97
Akhir
10
bantu

21. Middle Insertion (cont’d)
bantu↑.prev↑.next  baru
Awal
5 97
Akhir
10
bantu
baru 4
bantu↑.prev  baru

22. The last result for middle insertion if linked list
wasn’t empty:
Middle Insertion (cont’d)
Awal
5 97
Akhir
104
baru 4
Awal
5 97
Akhir
10
bantu

23. DELETION


24. • Delete one node in beggining of linked list if
linked list has only one node (awal = akhir).
Front Deletion
phapus  awal
Awal
Akhir
2
Awal
Akhir
2
Awal
Akhir
elemen  phapus↑.info
awal  nil
akhir  nil
dealloc(phapus)
menjadi

25. If deletion happens in linked list with one node
then linked list will be empty.
Front Deletion (cont’d)
2 4 5 9
Awal Akhir
phapus  awal
phapus
elemen  phapus↑.info
elemen

26. Front Deletion (cont’d)
2 4 5 9
Akhir
phapus
awal  awal↑.next atau awal  phapus↑.next
Awal

27. Front Deletion (cont’d)
awal↑.prev  nildealloc(phapus)
2 4 5 9
Awal Akhir
phapus

28. The last result for front deletion if linked list has
more than one node:
Front Deletion (cont’d)
4 5 9
Awal Akhir
4 5 9
Akhir
phapus 2
Awal

29. • Delete one node in back of linked list if
linked list has only one node (awal = akhir).
This process is same as front
deletion if linked list has
only one node.
Back Deletion

30. • If linked list has more than one node (awal ≠
akhir). For example, linked list has four
nodes.
Back Deletion (cont’d)
2 4 5 9
Awal Akhir
phapus  akhir
phapus
elemen  phapus↑.info elemen

31. Back Deletion (cont’d)
2 4 5 9
phapus
akhir  akhir↑.prev atau akhir  phapus↑.prev
Awal Akhir

32. Back Deletion (cont’d)
akhir↑.next  nildealloc(phapus)
2 4 5 9
Awal Akhir phapus

33. The last result for back deletion if linked list has
more than one node:
Back Deletion (cont’d)
2 4 5 9
Awal Akhir
phapus

34. • Middle deletion in double linked list is
similar as middle deletion
in single linked list.
Middle Deletion

35. Contact Person:
Adam Mukharil Bachtiar
Informatics Engineering UNIKOM
Jalan Dipati Ukur Nomor. 112-114 Bandung 40132
Email: adfbipotter@gmail.com
Blog: http://adfbipotter.wordpress.com
Copyright © Adam Mukharil Bachtiar 2012