Week 11 Notes for CS 2500, Section 001 -- Spring 2002

• Look at Upcoming Schedule
• Class starts at 09:40. I take roll at 09:50
• Announcement(s)
  • I will be absent on Thursday -- we will catch up with the material in these notes.
• Discuss Definition of the queue data type
  • Organization -- First-In, First-Out
  • Elements -- any given homogeneous set
  • Operations
    • constructor(s)
    • destructor(s)
    • bool QueueIsEmpty()
    • void QueueInsert(queueItemType NewItem, bool& Success)
    • void QueueDelete(bool& Success)
    • void QueueDelete(queueItemType& QueueFront, bool& Success)
    • void GetQueueFront(queueItemType& QueueFront, bool& Success)
• Discuss applications of the queue data type
  • Ready queue in an OS
  • Resource queues -- e.g. student registration system
  • Simulations -- e.g. traffic, airport, bank
  • Radix Sort
  • breadth-first search
• Discuss implementations of the queue data type
  • array-based implementation
  • pointer-based implementation (Work in some discussion of implementing the deque-as-doubly-linked-list.)
  • "as-a-list" implementations
• Discuss pro's and con's of different implementations
  • array-based implementation
    • PRO: simple code
    • PRO: all operations are O(1)
    • CON: static allocation
  • pointer-based implementation
    • PRO: dynamic memory allocation
    • PRO: most operations are O(1)
    • CON: destructor is O(N)
    • CON: extra memory required for each element.
  • "as-a-list" implementations
    • PRO: extremely easy to program
    • PRO: if done a certain way, can be as efficient as coding "from scratch." -- take care to make both insertion and deletion efficient.
    • PRO: can be done with an array-based list or with a pointer-based list.
• Start on Trees if time allows

• Look at Upcoming Schedule
• Class starts at 09:40. I take roll at 09:50
• Announcement(s)
• Discuss binary trees, tables, and binary search trees.
  • ADT binary tree -- the ADT is determined by these properties
    • Organization -- A binary tree is empty, or consists of a root with a left subtree and a right subtree. The subtrees are binary trees.
    • Elements -- any given homogeneous set
    • Operations -- see the file BT.h for the list and the specs.
  • ADT table -- see the specs in Carrano, Chapter 11, p. 529.
  • ADT binary search tree
    • Organization -- A binary search tree is a binary tree in which each node contains a key that is an element of a totally ordered set. For every node N in the tree, all keys in the left subtree of N are less than the key in N, and all keys in the right subtree of N are greater than the key in N.
    • Elements -- any given homogeneous set
    • Operations -- see the file BST.h for the list and the specs.
      • Discuss implementation of retrieval.
      • Discuss implementation of insertion.
      • Discuss implementation of traversal.
      • Discuss implementation of deletion.
  • What is the reason for using BST's?