Understanding Data Structures

What is a data structure?

• A data structure is a specialized format for organizing, processing, and storing data.

• A data structure is a method for writing code.

• A data structure is a programming language.

• A data structure is a type of computer program.

Name three types of data structures.

• queues

• trees

• arrays, linked lists, hash tables

• stacks

What is the difference between an array and a linked list?

• An array allows efficient insertions/deletions, while a linked list has a fixed size and slow access.

• An array and a linked list are the same in terms of size and access speed.

• An array is dynamic and allows fast access, while a linked list has a fixed size.

• An array has fixed size and allows fast access, while a linked list is dynamic and allows efficient insertions/deletions.

Explain the concept of a stack and its operations.

• A stack is a data structure that only supports a single operation: clear (remove all elements) and does not have a concept of order.

• A stack is a FIFO data structure with operations: enqueue (add), dequeue (remove), front (view front), and isFull (check if full).

• A stack is a LIFO data structure with operations: push (add), pop (remove), peek (view top), and isEmpty (check if empty).

• A stack allows random access to elements and has operations: insert (add), delete (remove), top (view any element), and isEmpty (check if empty).

What is a queue and how does it differ from a stack?

• A queue allows random access, while a stack does not.

• A queue is a FIFO data structure, while a stack is a LIFO data structure.

• A queue is a data structure that only allows insertion at the front.

• A queue is a LIFO data structure, while a stack is a FIFO data structure.

Define a binary tree and its properties.

• A binary tree is a structure with unlimited children per node.

• A binary tree is a linear data structure with a single path.

• A binary tree is a data structure where each node has at most two children, with properties including ordered subtrees and potential emptiness.

• A binary tree must always be complete and balanced.

What is the purpose of a hash table?

• The purpose of a hash table is to provide efficient data storage and retrieval.

• To encrypt sensitive information.

• To create a backup of data.

• To store data in a linear format.

Explain the term 'Big O notation' in the context of data structures.

• Big O notation only applies to sorting algorithms.

• Big O notation characterizes the efficiency of algorithms in data structures by expressing their time and space complexity in relation to the size of the input.

• Big O notation is used to compare different programming languages.

• Big O notation measures the physical size of data structures.

What are the advantages of using a graph data structure?

• Incompatible with most algorithms

• Advantages of using a graph data structure include efficient representation of relationships, support for complex queries, dynamic data handling, and suitability for algorithms like shortest path and connectivity.

• Limited to linear data representation

• Only suitable for small datasets

Describe the difference between linear and non-linear data structures.

• Linear data structures have a sequential arrangement, while non-linear data structures have a hierarchical or interconnected arrangement.

• Linear data structures can only hold one type of data.

• Non-linear data structures cannot store data sequentially.

• Linear data structures are always faster than non-linear structures.