Chapter 8Data Abstractions

Introduction to CS

1st Semester, 2015 Sanghyun Park

Outline Data Structure Basics Arrays Lists Stacks Queues Trees

Data Structure Basics The topic of data structures explores ways in which users

can be ________ from the details of actual data storage(__________)

The shape or size of data structures may or may not change over time (dynamic vs. static structures);____ structures are easier to manage than dynamic ones

A ______ is a memory cell that contains the address of another memory cell; the value in the pointer tells us where to find the data

Single Dimensional Arrays

If the first reading is at address x,the ith reading is located at address ________

Two Dimensional Arrays

Row major order vs. column major order If we let c represent the number of columns in an array,

then the address of the entry in the ith row and jth column will be ________________

x

Contiguous Lists List is a collection of entries that appear in a _____ order Lists appear in both static and dynamic forms Let us consider techniques for storing a list of names

in a machine’s main memory The simplest structure is a ___________ list

Linked Lists A contiguous list suffers disadvantages

when implementing ________ lists The problem encountered can be simplified

if we use _______ lists

Deleting an Entry From Linked List

Inserting an Entry Into Linked List

Supporting The Conceptual List To support the ________ to the list structure,

the programmer should write a collection of __________ for performing such activities as inserting a new entry and searching for an entry

The users do not concern whether the list structure is implemented as a contiguous structure or a linked one;the users only call the procedure like PrintList(CSI2106)

Stacks A _____ is a list in which all insertions and deletions are

performed at the _____ end of the structure

The last entry entered will always be the first entry removed – last-in, first-out (______) structure

The end of a stack at which entries are inserted and deleted are called the ____ of the stack

The process of inserting an entry on the stack is called a ____ operation, and the process of deleting an entry is called a ____ operation

Backtracking A classic application of a stack occurs when a program

unit requests the execution of a ________ As each procedure is called, a ______ to the return

location is pushed on a stack; as each procedure is completed, the top entry from the stack is extracted

Printing a Linked Listin Reverse Order (1/3)

Printing a Linked Listin Reverse Order (2/3)

Printing a Linked Listin Reverse Order (3/3)

Stack Implementation

Push operation needs a test if stack is ____ Pop operation needs a test if stack is _____

Queues A _____ is a list in which all insertions are performed at

____ end while all deletions are made at the ____ end

The concept of a queue is inherent in any system in which objects are served in the same order in whichthey arrive - first-in, first-out (_____) structure

The end at which entries are removed is called the ____

The end at which new entries are added is called the ___

Queue Implementation

Queue “Crawling” Through Memory

Circular Queue

An Example of an Organization Chart

Representation of a Tree

Tree Terminology

Binary Trees Binary trees are trees in which each node has at most

___ children

Such trees normally are stored in memory using a ______ structure similar to that of linked lists

Examples of Binary Trees

A Binary Tree Usinga Linked Storage System

A Binary Tree Stored Without Pointers

A Sparse Binary TreeStored Without Pointers

Binary Search Using Binary Trees

Binary Search Example

Depth-First Traversal

Preorder Traversal

Inorder Traversal

Postorder Traversal

Breadth-First Traversal