Chapter 8: Data Abstraction

Question 1

Lists

Answer 1

A list is a collection of data whose entries are arranged sequentially.
The beginning of a list is called head and the end is called tail

Question 2

Stacks

Answer 2

• A stack is a list which entries are removed and inserted only at the head
• The head of the stack if called top and the tail is called bottom
• Inserting an entry to a stack is called pushing, and removing an entry is called popping.
• Stack is a LIFO (Last-in-first-out) structure

Question 3

Queues

Answer 3

• A queue is a list in which entries are removed only at the head and inserted only at the tail
• Inserting an entry to a queue is called enqueuing, and removing an entry is called dequeuing.
• Queue is a FIFO (First in first out)

Question 4

Tree

Answer 4

• A tree is a collection of data whose entries have an hierarchical organization
• Each position in a tree is called a node, the single node at the top is called root node, and the nodes at the bottom are called leaf nodes.
• A node’s immediate descendants are called children and its immediate ascendant is called its parent.
• A tree where each node has at most two children is called a binary tree.

Question 5

Static versus dynamic data structures

Answer 5

• A static data structure can’t change its shape or size over time, but the content can be changed
• A dynamic structure can, on the other hand change its shape and size over time.
• Pointer is a location in memory that contains an address to some other location in memory
  A pointer is used to store and manage the addresses of dynamically allocated blocks of memory.

Question 6

User-defined data types

Answer 6

• Those data types which are defined by the user are called user-defined data types

Question 7

Abstract data types

Answer 7

• Data type that can include both data and functions (operations on the data)