C949v4 Study Guide

Question 1

What is the percentage of the assessment that explains algorithms?

Answer 1

29%

Question 2

What type of search algorithm is linear search?

Answer 2

A basic search algorithm that checks each element sequentially.

Question 3

What is binary search?

Answer 3

A search algorithm that finds the position of a target value in a sorted array by repeatedly dividing the search interval in half.

Question 4

Define Big O in the context of time complexity.

Answer 4

A notation used to describe the upper limit of the time complexity of an algorithm.

Question 5

What is the time complexity of Selection Sort?

Answer 5

O(n^2)

Question 6

What is the time complexity of Merge Sort?

Answer 6

O(n log n)

Question 7

What does .pop() do in stacks?

Answer 7

Removes and returns the top element from the stack.

Question 8

What is a hash table?

Answer 8

A data structure that uses a hash function to map keys to indices of an array for efficient storage and retrieval.

Question 9

What is the main distinction of a tuple?

Answer 9

Tuples are immutable, meaning their values cannot be changed.

Question 10

Fill in the blank: A _______ follows the Last-In-First-Out (LIFO) principle.

Answer 10

stack

Question 11

What is garbage collection?

Answer 11

A process by which a computer’s memory is automatically managed, freeing up memory no longer used.

Question 12

What are the two possible values of a Boolean data type?

Answer 12

true or false

Question 13

What is the function of a queue?

Answer 13

A collection of elements that follows the First-In-First-Out (FIFO) principle.

Question 14

What does a priority queue do?

Answer 14

Dequeues elements based on their priority rather than their insertion order.

Question 15

What is a binary search tree?

Answer 15

A binary tree where each node has at most two children, with the left child being less than the parent and the right child being greater.

Question 16

What are the main operations of a deque?

Answer 16

• append()
• appendleft()
• pop()
• popleft()

Question 17

What is the purpose of the modulo operator in hash tables?

Answer 17

To compute the index for storing the key in the hash table.

Question 18

What is the average-case time complexity for basic operations in hash tables?

Answer 18

O(1)

Question 19

What does tree traversal refer to?

Answer 19

The process of visiting each node in a tree in a specific order.

Question 20

What are the three types of tree traversal?

Answer 20

• Inorder Traversal
• Preorder Traversal
• Postorder Traversal

Question 21

What is the definition of a set?

Answer 21

An unordered collection of unique elements.

Question 22

What does the term ‘linked allocation’ refer to?

Answer 22

A memory allocation technique where memory is allocated in linked nodes.

Question 23

What is the difference between assignment and comparison in programming?

Answer 23

Assignment uses = to assign a value, while comparison uses == to check for equality.

Question 24

What is the definition of a stack?

Answer 24

A linear data structure that follows the Last In First Out (LIFO) principle.

Question 25

True or False: A dequeue allows adding and removing elements only from one end.

Answer 25

False

Question 26

What is a linked list?

Answer 26

A data structure consisting of a sequence of nodes, each containing an element and a reference to the next node.

Question 27

What is the main purpose of a dictionary in programming?

Answer 27

To store key-value pairs where each key maps to a value.

Question 28

What does 'peek' do in a stack?

Answer 28

Returns the top element of the stack without removing it.

Question 29

What is the underlying data structure of a priority queue?

Answer 29

Heap

Question 30

What is the syntax to create a list in Python?

Answer 30

[]

Question 31

What does the 'append()' command do in a list?

Answer 31

Adds an element to the end of the list.

Question 32

What is a dictionary?

Answer 32

A collection of key-value pairs where each key maps to a value.

Question 33

What does the 'Get' operation do in a dictionary?

Answer 33

Returns the value associated with a specified key.

Question 34

What is the purpose of the 'Set' operation in a dictionary?

Answer 34

Sets the value associated with a specified key.

Question 35

What does the 'Delete' operation do in a dictionary?

Answer 35

Removes a key-value pair from the dictionary.

Question 36

What is a hash table?

Answer 36

A data structure that uses hashing to store and retrieve key-value pairs efficiently.

Question 37

Define hashing in the context of hash tables.

Answer 37

The process of converting a key into an index that can be used to access a value in the hash table.

Question 38

What is chaining in hash tables?

Answer 38

A method for handling collisions by storing multiple key-value pairs in the same index.

Question 39

What is a hash key?

Answer 39

The result of hashing a key to determine its index in the hash table.

Question 40

What method is commonly used for hashing keys?

Answer 40

Modular Arithmetic.

Question 41

What is an array?

Answer 41

A data structure that stores a fixed-size sequence of elements of the same type in contiguous memory locations.

Question 42

How are elements compared in an array?

Answer 42

Elements are compared by their index.

Question 43

What is the time complexity for inserting an element at the end of an array?

Answer 43

O(1).

Question 44

What is the time complexity for deleting an element from the end of an array?

Answer 44

O(1).

Question 45

How are elements accessed in an array?

Answer 45

Using their index.

Question 46

What is the structure of arrays?

Answer 46

Arrays have a flat structure.

Question 47

What is a linked list?

Answer 47

A data structure that consists of a sequence of nodes, each containing an element and a reference to the next node.

Question 48

How are elements compared in a linked list?

Answer 48

Elements are compared by their value.

Question 49

What is the time complexity for inserting an element at the beginning of a linked list?

Answer 49

O(1).

Question 50

What is the time complexity for deleting a known node from a linked list?

Answer 50

O(1).

Question 51

How are elements accessed in a linked list?

Answer 51

By traversing the list from the beginning or end.

Question 52

What is a doubly linked list?

Answer 52

A data structure that consists of a sequence of nodes, each containing an element and references to the previous and next nodes.

Question 53

What is the time complexity for inserting an element at the beginning of a doubly linked list?

Answer 53

O(1).

Question 54

How are elements accessed in a doubly linked list?

Answer 54

By traversing the list from the beginning or end.

Question 55

What defines a queue data structure?

Answer 55

A structure that follows the First-In-First-Out (FIFO) principle.

Question 56

What is the time complexity for inserting an element into a queue?

Answer 56

O(1).

Question 57

What is the time complexity for deleting an element from a queue?

Answer 57

O(1).

Question 58

What defines a stack data structure?

Answer 58

A structure that follows the Last-In-First-Out (LIFO) principle.

Question 59

What is the time complexity for inserting an element into a stack?

Answer 59

O(1).

Question 60

What is the time complexity for deleting an element from a stack?

Answer 60

O(1).

Question 61

What is a binary tree?

Answer 61

A hierarchical data structure consisting of nodes connected by edges, where each node has at most two children.

Question 62

How are nodes compared in a binary tree?

Answer 62

Nodes are compared by their value.

Question 63

What is the method for inserting nodes in a binary tree?

Answer 63

By finding the appropriate location based on their value.

Question 64

What is a heap?

Answer 64

A specialized tree-based data structure used to maintain the maximum or minimum element in a collection.

Question 65

What defines a min-heap?

Answer 65

A binary heap where the value of each parent node is less than or equal to its children.

Question 66

What defines a max-heap?

Answer 66

A binary heap where the value of each parent node is greater than or equal to its children.

Question 67

How are nodes represented in a binary heap?

Answer 67

As a list, where the root node is at index 1.

Question 68

What is a graph?

Answer 68

A collection of nodes (vertices) connected by edges.

Question 69

What is the difference between directed and undirected graphs?

Answer 69

Directed graphs have edges with direction, while undirected graphs have edges with no direction.

Question 70

What are vertices in a graph?

Answer 70

The nodes in a graph.

Question 71

What are the methods for inserting elements in a graph?

Answer 71

By adding new vertices or edges.

Question 72

What is indexing in data structures?

Answer 72

The method used to access individual elements or nodes within a data structure.

Question 73

How does the hierarchy of a data structure impact indexing?

Answer 73

Linear structures like arrays are often accessed by index, while hierarchical structures like trees may use traversal methods.