Lecture 11

Learning objectives

After this class, you should be able to:

1. Explain the purpose of self-organizing lists.
2. Explain the method used by the following types of self-organizing lists: (i) move-to-front, (ii) transpose, (iii) count, and (iv) ordering.
3. Given a sequence of operations on a self organizing list of one of the above types, or a new type that we define, show the relative positions of elements in the list.
4. Write code to implement a specified operation on a self-organizing list, either of the above types, or of some new type.
5. Given an application, state which type of self-organizing list would ideally suit it, and give a justification for your choice.
6. Write code using the following features of an STL list class: back, front, push_back, pop_back, push_front, pop_front, begin, end, pop_back, pop_front, list(), erase, remove, size, merge, sort, and unique.

Reading assignment

1. Section 3.5 (except the amortized analysis on pages 105-106), section 3.7.
2. Section 2.8, page 63 and 64.

Exercises and review questions

• Exercises and review questions on current lecture's material
  1. Complete the table of figure 3.19, using the choices made in class. Note that our results differ from that in the book.
  2. Let s point to the node of a doubly linked list, which we have located in a search. Write code to adjust the position of this node in a move-to-front list.
  3. Let s point to the node of a doubly linked list, which we have located in a search. Write code to adjust the position of this node in a list that uses the count method. (Please do *NOT* post the solution on blackboard)
  4. Change the code of Lec10/toyll.cpp so that it uses the STL list class.
  5. Give an application where one of the self organizing lists is preferable to others, and justify you choice.

• Questions on next lecture's material
  1. When we search for an element in a linked list, we stop the search when we find an element. Assume that a list has n elements. What is the best case time complexity for the search? What is the worst case time complexity for the search?