Preparing for Coding Interviews: Advice From Codility's Task Creators

Programming interviews are probably not an everyday situation for you as a developer. The thought of them may even be intimidating – especially if you don’t have much experience with these situations and preparing for coding interviews seems like a guessing game.

Codility provides talent acquisition teams with an extensive library of programming tasks for various tech roles and experience levels to use during interviews and tests. Our Task Creators Community, composed of highly skilled developers from different fields, assists us with test creation. So we figured who better to help you prepare for programming interviews than them?

Read on to learn our Task Creators Community’s top three tips on how to master your next coding interview.

Tip#1: Keep a clear head

Surprisingly, our Task Creators Community’s top tip for preparing for coding interviews isn’t learning algorithms or knowing the ins and outs of all data structures. Instead, they think it’s more important to practice staying calm and collected in stressful interview situations.

When we asked Robert Piwowarek, Scala developer and gameplay programmer at PixelAnt Games, for his best advice, we got a quick and decisive answer: 

“Not stressing out – honestly, my best job interviews were those I didn’t really care about and treated like a chat with people about coding and figuring out issues.”

Of course, not everyone can become as relaxed as Robert – but you can still do the following to help keep a calmer attitude:

• Become familiar with how coding interviews work and what tools interviewers use
• Find out what recruiters really look for in a candidate
• Get moral support from friends and family
• Get comfortable with the idea that it’s okay to fail – it’s not the end of the world if something goes wrong
• Experiment with breathing and tapping exercises to relieve anxiety and stress

Tip#2: Practice solving coding tasks

What do you do to get better at solving Sudokus or playing the guitar? That’s right, you practice. So what do you do to get better at solving coding problems? You know it: only practice makes perfect.

First, you need valuable practice materials. 

Visit our Developer Training app to sharpen your problem-solving skills in our hands-on programming lessons. We also regularly host coding challenges and encourage you to participate to gain experience solving coding tasks under pressure and win great prizes!

Next, you may be wondering how best to solve these tasks. Unfortunately, there’s no magic formula here. However, task creator Robert advises, “Figure out a basic solution first, then poke holes in it and try to figure out better solutions that address them.”

The key word here is “solutions.” Always think of multiple solutions to a problem when preparing for coding interviews. 

“Don’t stick to one solution, experiment, and don’t get stuck on just one way,” Robert recommends. Practice this to stay calm and move on to another solution more quickly if you get stuck with your initial approach.

You might also like: Five Javascript Coding Interview Questions You’re Sure to Encounter

 Tip#3: Practice expressing your thoughts

The last big tip is to get used to talking while solving coding tasks. If you’ve worked closely with other developers before, such as in pair programming sessions or as a team leader, you’re probably already pretty good at this. Otherwise, add “practice speaking” to your interview preparation to-do list.

Your interviewer is not a mind reader. They need to know what you are thinking and doing to keep up with you. They will likely ask you many questions that could throw you off track if you don’t talk. Therefore, it is probably better if you speak without being asked.

Here’s what to talk about when solving a coding task:

1. When you receive the task. Never start coding immediately, but repeat the question in your own words to ensure you understand it correctly. Then ask questions that will help you clarify the scope and intent of the problem.
2. When you start thinking about possible solutions. Come up with an idea to solve the problem and discuss why this solution is good or not so good. Debate your approach with the interviewer and only start writing code once you both are okay with your idea.
3. When you’re writing code. It’s usually fine if you need to focus and can’t talk much, but make sure you reserve time slots where you explain what you’re implementing.
4. When you’re done. Finally, you will likely walk the interviewer through your program. Remember to mention your code’s time and space complexity, identify potential flaws, and suggest alternative solutions.

If you feel rushed by your interviewer to the point where you can’t concentrate, don’t hesitate to let them know. No one expects you to be a multitasking genius.

Develop a plan for preparing for coding interviews 

You’ll be a big step closer to a successful job interview if you follow the advice of our Task Creators Community to 

• Stay calm during stressful situations
• Practice solving coding tasks 
• Get comfortable talking about your ideas and code

If you’re overwhelmed with interview preparation, create a plan and track your progress. Use a calendar or a to-do management tool like Trello to stay organized. You can find many helpful articles and videos online that cover the various aspects of job interviews. Be sure to visit our blog and developer resources to learn more about code interviews with Codility tools.

Want more tips on preparing for a coding interview? Check out Codility Developer Training – an app where you can develop your coding skills with our lessons and participate in our challenges.