Best Interview Preperation Resources in 2025

Best Coding Interview Resources

This Blog contains the best resources for Coding Interview prep.

💡 How to Think of Logic

1. Break Down the Problem: Read the question twice. Identify inputs, outputs, and constraints.
2. Start with Examples: Create test cases manually and simulate the solution step-by-step.
3. Write Pseudocode: Draft a high-level plan before coding.
4. Ask “Why?” at Every Step: Understand each operation; don’t memorize solutions.
5. Visualize: Use diagrams or dry-run tables to debug.
6. Optimize Gradually: Start with brute force; iterate to optimize for efficiency.

Some Strategies to follow

1. ⁠ ⁠Spend 1 hour revising concepts: Have a look at previously solved questions, what concepts did you apply and how much time you spent.
2. ⁠Spend 1 hour learning new concepts: Pick a new topic, spend 1 hour watching video tutorials on it
3. ⁠Spend 2-3 hours solving questions: Practice, practice, practice. Aim to solve at least 5-6 questions within this duration

You can adjust the timeline above according to your schedule.

Here are a few tips on how to Leetcode efficiently:

1. Solve with a timer : 25 mins for medium level problems and 35 mins for hard level problems. If you’re not able to solve in this duration, you won’t be able to solve it, so its ok to have a look at solutions and understand the solution
2. ⁠Revise questions and concepts: Install Leetcode reminder chrome extension to solve previously solved questions
3. ⁠Don’t focus on the X number of problems : It doesn’t matter if you solve 100 or 1000 questions. What matters is the level of understanding and knowledge you gain by solving these questions. So focus on that, always.

LeetCode Company Wise Coding Question

A-TO-Z Resources

Data Structures & Algorithms

• Hash Tables
• Linked List
• Recursion
• Sorting
• Binary Search
• Stacks
• Queues
• Trees
• Tries
• Backtracking
• Heaps
• Breadth First Search
• Depth First Search
• Graph Theory
• Dynaymic Programming
• Big O Cheat Sheet

Leetcode Spaced-Repetition Template

Patterns

• 14 Coding Interview Patterns
• Sliding Window
• Two Pointers
• Merge Intervals
• Cyclic Sort
• Monotonic Stack
• Two Heaps
• Subsets
• Modified Binary Search
• Top K Elements
• K-way merge
• In-place Reversal of Linked List
• DFS Pattern
• BFS Pattern
• O-1 Knapsack
• Topological Sort

Famous Problem Sets

• Blind 75
• Neetcode 150
• Sean Prashad’s Leetcode Patterns
• Leetcode Top Interview Questions

Books

• Elements of Programming Interviews
• Competitive Programmer’s Handbook

Download the PDF of Cracking the Coding Interview

Courses

• Grokking the Coding Interview
• Data Structures with a Google SWE
• Meta Coding Interview Prep Course

Mock Interviewing

• Pramp
• Interviewing.io
• Meetapro

LeetCode Extensions

• LeetCode Video Solutions
• LeetCode GitHub Submission Sync
• LeetCode VS Code Extension

Resume Template

📚 100 DSA Questions for Logic Building

Category	Question Name	Platform	Link
Basics & Warm-Up	Print a pattern of stars (triangle, pyramid)	GeeksforGeeks	Link
	Reverse a number	GeeksforGeeks	Link
	Check if a number is palindrome	GeeksforGeeks	Link
	Count digits in a number	GeeksforGeeks	Link
	Find factorial of a number	HackerRank	Link
Arrays	Reverse an array	LeetCode	Link
	Find the maximum and minimum of an array	GeeksforGeeks	Link
	Rotate an array by K steps	LeetCode	Link
	Move all zeroes to the end	LeetCode	Link
	Kadane’s Algorithm (Maximum Subarray Sum)	LeetCode	Link
Strings	Reverse a string	LeetCode	Link
	Check if two strings are anagrams	LeetCode	Link
	Longest Common Prefix	LeetCode	Link
	Check if a string is a palindrome	LeetCode	Link
	Count and say	LeetCode	Link
Recursion	Fibonacci series using recursion	GeeksforGeeks	Link
	Tower of Hanoi	GeeksforGeeks	Link
	Factorial using recursion	LeetCode	Link
	Reverse a linked list using recursion	LeetCode	Link
	Permutations of a string	GeeksforGeeks	Link
Sorting	Bubble sort	GeeksforGeeks	Link
	Selection sort	GeeksforGeeks	Link
	Merge sort	GeeksforGeeks	Link
	Quick sort	GeeksforGeeks	Link
	Insertion sort	GeeksforGeeks	Link
Searching	Binary search	LeetCode	Link
	Linear search	GeeksforGeeks	Link
	Search in a rotated sorted array	LeetCode	Link
	First and last position in a sorted array	LeetCode	Link
	Square root of a number (using binary search)	LeetCode	Link
Linked List	Reverse a linked list	LeetCode	Link
	Detect a cycle in a linked list	LeetCode	Link
	Merge two sorted linked lists	LeetCode	Link
	Remove Nth node from the end	LeetCode	Link
	Find the middle of a linked list	LeetCode	Link
Stacks & Queues	Implement a stack using arrays	LeetCode	Link
	Evaluate postfix expression	GeeksforGeeks	Link
	Balanced parentheses	LeetCode	Link
	Next greater element	LeetCode	Link
	Implement a queue using stacks	LeetCode	Link
Dynamic Programming	0/1 Knapsack problem	GeeksforGeeks	Link
	Fibonacci using dynamic programming	LeetCode	Link
	Longest common subsequence	LeetCode	Link
	Longest increasing subsequence	LeetCode	Link
	Minimum steps to reach the end	LeetCode	Link
Graphs	BFS traversal	GeeksforGeeks	Link
	DFS traversal	GeeksforGeeks	Link
	Detect cycle in an undirected graph	GeeksforGeeks	Link
	Shortest path in a graph (Dijkstra’s)	GeeksforGeeks	Link
	Topological sort	GeeksforGeeks	Link

Must-do Problems

Graphs

• Redundant Connection
• Course Schedule
• Course Schedule II
• Number of connected components in an undirected graph
• Shortest Path to Get All Keys
• Pacific Atlantic Waterflow
• Word Ladder
• Number of Islands
• Clone Graph
• Alien Dictionary

Binary Trees

• Construct binary tree from preorder and inorder traversal
• Diameter of Binary Tree
• Invert Binary Tree
• Count good nodes in Binary Tree
• Serialize and Deserialize Binary Tree
• Kth smallest element in BST
• Lowest Common Ancestor of a BST
• Path Sum
• Path Sum II
• Merge two Binary Trees
• Word Search
• Word Search II
• Maximum Width of Binary Tree

Linked Lists

• Reverse Linked List
• Reverse Linked List II
• Rotate List
• Odd Even Linked List
• Swap Nodes in Pairs
• Reverse nodes in K group
• LRU Cache