5 Common Mistakes in Coding Interviews (And How to Avoid Them)

Coding interviews at top tech companies are stressful, and even experienced engineers make avoidable mistakes. Here are the five most common ones and how to fix them.

Mistake 1: Jumping into code immediately. Interviewers want to see your thought process. Spend 3-5 minutes understanding the problem, asking clarifying questions, and discussing your approach before writing a single line of code.

Mistake 2: Ignoring edge cases. Empty arrays, null inputs, single-element lists, negative numbers, integer overflow. Mention these proactively. It shows thoroughness and maturity.

Mistake 3: Not testing your code. After writing your solution, trace through it with a simple example. Walk the interviewer through your logic step by step. Catch bugs before they point them out.

Mistake 4: Optimizing too early. Start with a brute force solution. Get it working. Then optimize. Interviewers prefer a working O(n2) solution over a broken O(n log n) attempt.

Mistake 5: Poor communication. Talk while you code. Explain what you are doing and why. If you get stuck, say so — "I am thinking about whether a hash map would work here because..." is much better than silence.

Interview AI Buddy helps with all five — it suggests approaches, catches edge cases, and provides complexity analysis in real time while you code.

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