Mastering Data Structures

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

• Linked lists allow index-based access while arrays do not.

• Arrays can grow dynamically while linked lists have fixed sizes.

• Arrays consist of nodes linked by pointers, while linked lists do not.

• The main difference is that arrays have fixed sizes and allow index-based access, while linked lists are dynamic and consist of nodes linked by pointers.

How do you insert an element at the beginning of a linked list?

• Remove the current head and replace it with the new node.

• Create a new node, set its next to the current head, and update the head to the new node.

• Add the element to the end of the list.

• Insert the element in the middle of the list.

What is a stack and how does it operate?

• A stack is a LIFO data structure that allows push and pop operations.

• A stack is a type of queue that operates on a first-in, first-out basis.

• A stack is a FIFO data structure that allows enqueue and dequeue operations.

• A stack is a data structure that only allows insertion of elements without removal.

Explain the concept of a queue and its applications.

• Queues are not applicable in web development.

• Queues are primarily for storing data permanently.

• Queues are used for sorting algorithms only.

• Queues are commonly used in applications such as task scheduling, print job management, and handling requests in web servers.

What is the time complexity of accessing an element in an array?

• O(1)

• O(n^2)

• O(log n)

• O(n)

Describe the structure of a binary tree.

• A binary tree can have any number of children per node.

• A binary tree is a linear structure with nodes connected in a single line.

• A binary tree consists of nodes with three children each.

• A binary tree consists of nodes, where each node has at most two children (left and right), with a single root node at the top.

What is a binary search tree and how does it differ from a regular binary tree?

• A binary search tree is a binary tree that does not allow duplicate values, unlike a regular binary tree.

• A binary search tree can only contain integer values, while a binary tree can contain any data type.

• A binary search tree is a type of linked list with unordered nodes.

• A binary search tree is a binary tree with ordered nodes, allowing efficient search, insertion, and deletion, unlike a regular binary tree.

How do you perform preorder traversal?

• First visit left child, then right child and finally root node

• First visit right child, then left child and finally root node

• First visit root node then left child and finally right child

• First visit root node then right child and finally left child

What is the purpose of a sorting algorithm?

• To compress data to save space.

• The purpose of a sorting algorithm is to arrange data in a specified order.

• To encrypt data for security purposes.

• To generate random data for testing.

Name and describe one efficient sorting algorithm.

• InsertionSort

• SelectionSort

• QuickSort

• BubbleSort