Tutorial 3 - Linked List

1. Tutorial 3 - Linked List

2. Linked List: Revision Reserved for next week… • The concept of ADT List • ADT List using Array • Pro & cons  Discussed in T02Q3and today in Q1! • ADT List using Linked List • Basic idea: Slide 17 • Linked List Node has 2 parts: • Item/Value/Content  See T03Sup1&2 • Pointers to immediate neighbors • Single Linked List • The basic; traversal: head to tail • Usually: insert from head (ok for Stack) • In your lecture notes: BasicLinkList (Slide 26-28), ExtendedLinkedList (Slide 29-36) • Generic Java (Slide 37-46) for our custom Basic and Extended LinkedList • Linked List Variations: • Linked List with Tail Pointer • Can visit the tail very fast  • Cannot delete the tail easily…  • In lecture notes (Slide 48-53): TailedLinkedList(revisited in Queue data structure later) • Bidirectional Linked List • Two pointers: forward/backward • Can go backwards, Can delete tail!  • Extra pointer is overhead  • In lecture notes (Slide 54-58):DoublyLinkedList • Circular Linked List • Remember Tail only, Head = Tail.Next • Can visit all node from any node . • Generic LinkedList<E> (slide 61-66) for a “bug-free”, “ready-to-use” LL 

3. Student Presentation • T3 Sup1. Ng Hong Geh Sup2. N/A • KohXianghua, Nicholas (deferred until next week) • N/A • N/A • SeoJia Wei David • T4 Sup1. Chong TzeKoi Sup2. Chong TzeKoi • Tan MiangYeow • N/A • N/A • N/A • T5 Sup1. Wang Ruohan Sup2. Zhang Denan, Zhang Yang • N/A • N/A • N/A • N/A • T6 Sup1. N/A Sup2. N/A • Kuganeswari D/O Kuhanesan (deferred until next week) • N/A • N/A • KohJyeYiing Hm… not that good… Anyone wants to take Sup1 & Sup2 questions?

4. Question Supplementary 1 ListNode First = new ListNode(“first”); ListNode Last = First; ListNode Temp; for (int j = 1; j < 6; j++) if (j % 2 == 0) { Temp = new ListNode(“j = “ + j); Last.next = Temp; Last = Temp; } else First = new ListNode(“j = “ + j, First); Trace this!

5. Question Supplementary 2 Now, rearrange: J=5  J=3  J=1  first  J=2  J=4 into first  J=1  J=2  J=3  J=4  J=5

6. Question 1 (MovieDataAnalysis) • (Prologue) Array Based ADT (Lect 3, Slide 6-15) • Pros? • Cons? • Real question: Insert New Item (Movie ADT) to LinkedList • Ensure that you check for duplicate data!

7. Question 2 (MovieDataAnalysis) • Given time period (yearA – yearB) • Get movies that are produced within that range. • Methods • 1: Scan and select the appropriate movies • 2: Copy the list and delete movies that are out of range • What if we use Doubly Linked List? • Pro and Cons? 2008 2007 2007 2008 2006

8. Question 3 (MovieDataAnalysis) • Given two TopList containing movies, perform: • Intersection • Union • Difference • Remember that A-B is not the same as B-A! Person A’s preference: Person B’s preference:

9. Question 4 (Guess Output) • ExtendedLinkedList list = new ExtendedLinkedList();list.addHead(“ZZZ”); list.addHead(“YYY”); list.addHead(“XXX”);list.addHead(“WWW”); list.addHead(“VVV”); • A: ListNode node = list.getHeadPtr(); printList(node); • VVV, WWW, XXX, YYY, ZZZ • B: System.out.println(node.next.next.next); • YYY • C: node = node.next(), printList(node); • WWW, XXX, YYY, ZZZ • D: node = list.getHeadPtr(); list.deleteAfter(node); printList(node); • VVV, XXX, YYY, ZZZ • E: ListNode fNode = new ListNode(“FFF”, node); node.next = fNode;printList(node); • VVV, FFF, VVV, FFF, … (infinite)

10. Next Week • Revisit the leftover materials from today’s tutorial • Revise stack/queue • ThisWeek.Next.Next is recess week • Use your recess week carefully! • CS1102 midterm test is just one week after it!