How to Crack Your First Tech Interview
A step-by-step roadmap to preparing for and clearing technical interviews at Indian product companies and MNCs.
Understanding the Interview Process
Most tech companies in India follow a structured interview process. Understanding each stage gives you a strategic advantage:
Online Assessment (OA)
Usually 2-3 coding problems on platforms like HackerRank or Codility. Time limit: 60-90 minutes. Focus: Arrays, Strings, Sorting, Basic DP.
Technical Round 1 (DSA)
Live coding round with a senior engineer. Expect 1-2 medium difficulty problems. You must think out loud and communicate your approach.
Technical Round 2 (System Design / Deep Dive)
For freshers: LLD (Low-Level Design) or a project deep-dive. For experienced: HLD (High-Level Design) like designing a URL shortener or chat system.
HR / Managerial Round
Behavioral questions, salary discussion, and culture fit assessment. Often underestimated but can be a dealbreaker.
The 90-Day DSA Preparation Plan
You do not need to solve 1000 LeetCode problems. A focused preparation of 150-200 carefully chosen problems is far more effective. Here's a proven plan:
Month 1: Build Foundations
- Week 1-2: Arrays, Strings, and Hashing — practice 20 problems each
- Week 3: Linked Lists and Two Pointers technique
- Week 4: Stacks, Queues, and Sliding Window
Month 2: Core Algorithms
- Week 5-6: Binary Search (on arrays and on answer) and Sorting algorithms
- Week 7: Trees (BFS, DFS, BST) and Recursion
- Week 8: Graphs (BFS, DFS, Dijkstra, Topological Sort)
Month 3: Advanced Topics + Mock Interviews
- Week 9-10: Dynamic Programming (start with easy ones, then medium)
- Week 11: Greedy algorithms, Tries, and Bit Manipulation
- Week 12: Mock interviews on Pramp or with friends — simulate real conditions
Top Resources for Preparation
Most popular DSA sheet in India. Covers 450+ problems organized by topic.
Curated list of 150 LeetCode problems covering all major patterns.
The standard platform for practicing coding problems. Focus on Medium difficulty.
Great for learning concepts and reading editorial solutions in multiple languages.
Free, comprehensive guide to system design concepts for beginners.
Common Mistakes to Avoid
- Jumping to code immediately: Always spend 3-5 minutes understanding the problem, clarifying edge cases, and explaining your approach first.
- Ignoring time complexity: Always analyze and state the time and space complexity of your solution. Interviewers expect this.
- Not practicing out loud: Technical interviews are verbal. Practice explaining your thought process while coding.
- Only solving, never reviewing: After solving a problem, read the optimal solution and understand WHY it works.
- Neglecting the HR round: Prepare your "Tell me about yourself", "Why this company?", and "Where do you see yourself in 5 years?" answers in advance.
Day-Of Tips
- Join the call 2 minutes early and test your mic/camera
- Keep a glass of water nearby
- Have pen and paper for rough work
- If stuck, tell the interviewer — they will often give hints
- Thank the interviewer at the end and ask one thoughtful question about the team/product