1.4.2 Data Structures

Question 1

what is the difference between static and dynamic structures

Answer 1

static structures have a fixed length while dynamic structures have a changeable length

Question 2

what is the difference between an array and a tuple(1)

Answer 2

Tuples are immutable (data cannot be changed), arrays can be modified(1)

Question 3

what is a 2d array

Answer 3

a 2d array is an array that contains other arrays

Question 4

what is a queue

Answer 4

a static first in first out structure for ordering data

Question 5

what is an abstract data structure

Answer 5

a data structure made by the programmer

Question 6

what is a list

Answer 6

an abstract data structure which stores a number of items

Question 7

what is a linked list

Answer 7

an abstract dynamic data structure to ordered data from different locations

Question 8

what is a stack

Answer 8

a last in first out data structure used to store instructions

Question 9

what does the purpose of the call stack

Answer 9

to hold the active suboutines and their data

Question 10

what is the difference between a list and a stack

Answer 10

a list is first in first out a stack is last in first out

Question 11

what is the difference between a weighted and unweighted graph

Answer 11

with a weighted graph each edge has a value with an unweighted graph edges have no value

Question 12

what is the difference between a directed and undirected graph

Answer 12

with a directed graph edges can only be traversed in one direction with an undirected graph they can be traversed in any direction

Question 13

what is an adjacency matrix

Answer 13

a table to show the relationships in a graph

Question 14

what is a tree

Answer 14

an abstract data structure used to represent structures making data easier to search

Question 15

what is a Root Parent and Child

Answer 15

root: node with no incoming edges parent: a node with an outgoing edge child: a node with an incoming edge

Question 16

what is the difference between depth and breadth first traversal

Answer 16

depth: explore the entirety of a route before continuing to the next breadth: checking all available roots from a node before progressing

Question 17

what is a binary search tree

Answer 17

a rooted tree each node has a maximum of 2 children

Question 18

Describe the difference between an array and a linked list.(2)

Answer 18

A linked list is a dynamic data structure (1) whereas an array is static (1).

Question 19

Define the term ‘array’. (2)

Answer 19

A data structure (1) Has a single identifier (1).

Question 20

Describe what is meant by the term ‘linked list’ (3)

Answer 20

A data structure (1) Each node consists of data and pointer. (1) Pointer gives location of next node (1)

Question 21

State which of a stack or queue would be considered as a ‘First In First Out’ data structure.(1)

Answer 21

A queue (1)

Question 22

What is meant by a ‘tuple’? (3)

Answer 22

A tuple is an ordered sequence of elements that is immutable (1) which means that the values within the tuple cannot be modified when the program is running (1) . The elements of a tuple can be of different data types (1)

Question 23

What is meant by a ‘list’? (3)

Answer 23

A list is an abstract data type (1) that describes a linear collection of data items in some order (1) in that each element occupies a specific position in the list.(1)

Question 24

What is meant by a ‘record’

Answer 24

A record is a data structure (1) that consists of a fixed number of variables called fields (1) . Each field in a record can have a different data type (1)

Question 25

State the meaning of the term static.(1)

Answer 25

Size is fixed when structure created cannot change during processing (1)

Question 26

State one type of data structure that is always considered to be static.
(1)

Answer 26

Array (1)

Question 27

State the meaning of the term dynamic.(1)

Answer 27

Size can change during processing (1)

Question 28

Give one disadvantage of using a dynamic data structure.(1)

Answer 28

Storage required is unknown initially (1) OR more difficult to program (1)

Question 29

How would you add a new value to an unordered linked list? (3)

Answer 29

Create a node with the value (1) and set the next pointer to the value of the head pointer (of the linked list) (1) and set the head pointer (of the linked list) to point to the new node (1)

Question 30

What is meant by a graph having a loop? (1)

Answer 30

It has an edge that connects a node to itself (1)

Question 31

What is meant by the path of a graph? (1)

Answer 31

It is the sequence of nodes that are connected by edges (1)

Question 32

What is meant by the degree of a node? (1)

Answer 32

The number of other nodes that it is connected to (i.e. the number of neighbours it has) (1)

Question 33

Define the term ‘stack’. (4)

Answer 33

It is an abstract data type (1) that holds an ordered (1) linear sequence of items (1). It is a last in first out structure (1)

Question 34

Define the term ‘queue’. (4)

Answer 34

It is an abstract data type (1) that holds an ordered (1) linear sequence of items (1). It is a first in first out structure (1)

Question 35

Define a ‘binary tree’. (2)

Answer 35

It is a rooted (1) tree where every node has at most two children (1)