Introduction

This is my knowledge base of all the things I have learnt during prepping for technical interviews. If you are a beginner to leetcode, here is a good video introduction on how to get started with leetcode in 2025.
Once you are familiar with what is leetcode, why it is important, I would highly recommend just going through Neetcode's roadmap of top 150 questions here or top 300 questions here.
If you truly understand how most of the problems work in each category you are well prepared to give a regular technical interview. Your primary goal while preparing should be to understand the different patterns and practicing applying them. Read this article to get a quick intro on the important patterns.
I would also recommend reading through the Interview Handbook.

Interview Patterns

I am learning the common technical interview patterns from this course.

Topics

• Two Pointers
  • Opposite Direction Pointers (Start–End)
  • Same Direction Pointers (Sliding Window)
  • Fast & Slow Pointers (Tortoise–Hare)
  • Partitioning Pointers
  • K-Distance Apart
  • Merge-Style Pointers
• Prefix Sum
• Binary Search

Algorithms

• Boyer-Moore Voting
• Sorting Algorithms

Articles

• LeetCode was HARD until I Learned these 15 Patterns
• 20 Patterns to Master Dynamic Programming
• How to make progress while studying for coding interviews

Cheatsheets

• During Interview
• Big-O Algorithm Complexity Cheat Sheet
• General DSA flowchart
• Input sizes vs time complexity
• Python Cheatsheet and Python Cheat Sheet for Leetcode
• Tech Interview Cheat Sheet
• Code Templates
• Coding Interview Patterns
• Grokking Interview Topics