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Technical Interview Preparation Guide

Master coding interviews, system design, and technical screenings with proven strategies.

Introduction

Technical interviews assess how you think under pressure. This guide offers a concrete action plan to avoid 'LeetCode burnout' and focus on the fundamentals.

Types of Technical Interviews

Algorithms & Data Structures

Live Coding tests where you solve algorithmic problems. The key is not memorizing code, but patterns.

Input: [2, 7, 11, 15], target: 9 → Output: [0, 1] (Two Sum)

System Design

For Mid/Senior roles. Design scalable architectures (e.g., Twitter, Netflix).

Load Balancers, SQL vs NoSQL, Caching, Sharding.

Take-Home Projects

Projects to do at home. Code quality, testing, and documentation are evaluated.

Debugging / Code Review

Fix bugs or critique existing code. Look for 'Code Smells' and security issues.

Algorithm Strategy

Don't memorize solutions. Recognize patterns. Here are the most common ones:

Essential Patterns (Blind 75)

  • Sliding Window (Arrays/Strings)
  • Two Pointers (Sorted lists)
  • Fast & Slow Pointers (Linked List cycles)
  • Merge Intervals (Time ranges)
  • Cyclic Sort (1-N numeric arrays)
  • Tree BFS / DFS (Graphs and Trees)
  • Top 'K' Elements (Heaps)
  • Dynamic Programming (Optimization)

The Hidden Key: Communication

Silence is your enemy. Use the REACTO protocol to structure your thinking:

REACTO Protocol

  • Repeat: Repeat the question to confirm understanding.
  • Examples: Create example inputs/outputs and edge cases.
  • Approach: Describe your solution at a high level before coding.
  • Code: Write clean, readable code.
  • Test: Do a manual 'Dry Run' with your examples.
  • Optimize: Analyze complexity (Big O) and improve.

Conclusion

Deliberate practice beats talent. Treat the interviewer as a colleague and collaborate.