Mastering Data Structures

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

• O(n)

• O(log n)

• O(n^2)

• O(1)

Explain the difference between a stack and a queue.

• Both stack and queue use LIFO.

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

• A stack uses FIFO, while a queue uses LIFO.

• A stack uses LIFO, while a queue uses FIFO.

What is a linked list, and how does it differ from an array?

• A linked list stores elements in a single block of memory.

• An array is a dynamic structure with nodes linked together.

• A linked list is a static data structure with fixed-size elements.

• A linked list is a dynamic data structure with nodes linked together, while an array is a fixed-size collection of elements stored in contiguous memory.

Describe the concept of a binary tree and its properties.

• A binary tree is a data structure where each node has at most two children.

• A binary tree is a data structure where each node can have any number of children.

• A binary tree is a linear data structure that stores elements in a single line.

• A binary tree is a type of graph that can have cycles and multiple connections.

What is a hash table, and how does it handle collisions?

• A hash table is a method for encrypting sensitive information.

• A hash table is a type of database that stores large amounts of data.

• A hash table uses a binary tree structure to manage data.

• A hash table is a data structure that stores key-value pairs and handles collisions using methods like chaining or open addressing.

Explain the difference between depth-first search and breadth-first search.

• DFS uses a queue for exploration, while BFS uses a stack.

• DFS explores all neighbors at the current level first, while BFS goes deep into branches first.

• BFS is faster than DFS in all scenarios.

• DFS goes deep into branches first, while BFS explores all neighbors at the current level first.

What are the advantages of using a graph data structure?

• 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.

• Inefficient for simple queries

• Only suitable for static data

• Limited to linear data representation

Define what a balanced tree is and give an example.

• A binary tree is always balanced.

• An example of a balanced tree is an AVL tree.

• A red-black tree is an example of a complete tree.

• A balanced tree has no nodes.

What is the purpose of a priority queue?

• The purpose of a priority queue is to manage a collection of elements where each element has a priority, enabling efficient access to the highest (or lowest) priority element.

• To allow duplicate elements without priority

• To provide random access to elements

• To store elements in a sorted order

How do you implement a circular linked list?

• Create a doubly linked list instead.

• Use an array to store the nodes.

• Define a node structure, create a head pointer, and link the last node to the head.

• Link the head node to the last node directly.