Are you preparing for a live coding interview? If so, you’re probably feeling the pressure to perform. Live coding interviews can be intimidating and challenging, but with the right preparation and mindset, they don’t have to be.
In this blog post, we’ll cover what to expect during a live coding interview and how to prepare for one in order to increase your chances of success. We’ll also discuss some tips on dealing with nerves and performance issues that may arise during the actual interview process. With these insights in hand, you’ll feel more confident going into your live coding interview!
What Is a Live Coding Interview?
A live coding interview is a present-time face-to-face assessment, in which an interviewee demonstrates their coding abilities by solving a challenge problem. This usually takes place online with the use of an online coding editor with a limited amount of time to solve the problem(s). Alternatively, a whiteboard may be used for an in-person coding interview.
In the interview process, the candidate’s code and problem-solving abilities are thoroughly reviewed by the interviewer to determine if they should move forward. A coding assessment can be a part of a full-time job or an internship application.
Unlike other type of assessments, like a take-home coding challenge or any asynchronous assessment that only reveal the final output, live code testing allows you to demonstrate your problem solving skills in real time.
With this type of test you get to showcase everything from creativity and communication techniques all at once during an interview – something which can be great for exhibiting how capable you really are!
Pros and Cons of Live Coding Interviews
While live coding interviews are undoubtedly a great tool for candidate assessment and selection in the world of software engineering, they have also received plenty of criticism from applicants and interviewers alike. Let’s review the pros and cons of live coding interviews.
Pros
One of the biggest advantages of live coding assessment for both employers and candidates is that you get to show and observe the process, not just the result of a candidate’s problem-solving abilities. This helps you get a better understanding of their technical skills, creativity and communication techniques.
Additionally, live coding interviews can be great for quickly assessing a candidate’s fit with a company’s culture, as the interviewer can observe their problem-solving approach and communication during live coding.
Finally, live coding interviews provide an opportunity to assess a candidate’s comfort level with different programming languages and tools that the employer requires.
Cons
The biggest issue with live coding interviews is that they can be incredibly stressful for the candidate, as they’re essentially being observed and judged in real time. This can make it difficult for the candidate to really showcase their full capabilities, as well as make them feel more anxious.
The live coding interview also has a time limit, which can lead to rushed code and lack of readability. This could potentially lead to more errors in the code and make it harder for the interviewer to accurately assess the candidate’s problem-solving abilities.
Lastly, the content of the coding interviews isn’t always realistic. For example, you may be asked to solve a bubble sort problem during your interview, while the job doesn’t actually require you to ever use this type of coding strategy and instead focuses on, say, front-end web development.
What Tasks Will I Need to Solve?
Although no two coding assessments are same, even within the same company, there are certain types of topics that are commonly asked on a regular basis. These include manipulations of strings, arrays, linked lists, and other data structures.
You may also be asked to demonstrate your knowledge of algorithms and problem solving. This may include topics such as graph traversal, sorting algorithms, searching algorithms, and more.
Another frequent topic is coding challenges. These are problems that require advanced problem solving skills beyond the normal scope of live coding interviews. They often require you to come up with a creative solution to a complex problem in order to pass the live coding interview.
Life Coding Practice Questions
In order to better understand what to expect during live coding interviews, we will provide you some common problems that are asked during these assessment. However, make sure to broaden your preparation materials, as there are many more topics that can come up in live assessments that you should certainly be prepared for.
- “Find the size of a set.”
- “Remove duplicate elements from ArrayList.”
- “Do X to an array, or a 2D array.”
- “How to calculate the number of vowels and consonants in a string?”
- “How do you prove that the two strings are anagrams?”
- “How to search a missing number in an array that contains integers from 1 to 100?”
- “How to delete the repeated elements in an integer array?”
- “How to traverse to the middle of a linked list?”
You can find the answers to these problems, as well as many more here.
How Much Time Will I Have to Solve the Problems?
Typically, live coding interviews are timed and you’ll have anywhere between 30 minutes to an hour to solve the problem.
Some larger tech companies, such as Google and Amazon, will often have much longer coding interviews. Amazon is known for having a lengthy coding assessment round that consists of 4-6 problems, each with a 30-60 min time limit.
It is best to check with the company hosting the live coding interview to find out how much time you’ll have beforehand. They will usually provide instructions themselves or won’t mind answering your questions about the logistics prior to the interview.
Which Language Will I Need to Code in During the Interview?
More often than not, you are allowed to pick a language for live coding assessment on your own, unless you are applying for a position that deals with a specific programming language, such as Java developer or Ruby on Rails developer.
However, it is best to ask your interviewer about their preference/rules beforehand, so you know what to expect during the interview itself.
If you are told that choosing a programming language is up to you, it is a good idea to either pick a language that you are most comfortable in or a language that the company states it uses often, although the former criterion is more important.
How Difficult Is the Live Coding Interview?
Live coding interviews are usually not too difficult, unless you are applying to a very competitive company or a senior position. Remember that since you only have around 40 minutes to solve a problem, it is usually in the employer’s interest to come up with realistic and solvable problems for that timeframe.
Generally speaking, the coding interviews will usually involve questions approximately the difficulty of easy or medium on LeetCode.
Some Big Tech companies will ask you several problems with increasing level of difficulty, with the most difficult questions in the end.
Remember, that it is not a hard requirement to completely and flawlessly solve a problem during a technical interview. Instead, it is more important to show the correct and reasonable problem-solving skill to the interviewer.
How To Prepare for a Live Coding Interview
Live coding interviews require a lot of preparation, but it is worth the effort. Here are some strategies and preparation points for you to go over before your interview. Remember, you should start preparing for coding interviews 2-3 months in advance for best results and practice, practice, practice!
First of all, review these topics:
- Data structures
- Arrays
- Hash tables
- Heaps
- Search algorithms
- Dynamic programming
- Trees
These are the most commonly asked about topics for live coding interviews, so it’s important to make sure you understand them thoroughly. If you are not sure where to start, we recommend the following resource:
- Introduction to Algorithms — MIT Press
- Data Structures Explained — freeCodeCamp
- Dynamic Programming Exercises — leetcode
Beyond familiarizing yourself with the above topics, it’s also important to practice live coding interviews. You can find a lot of coding resources online and these are especially helpful when you are preparing for live coding interviews.
Some of our favorite resources for practicing interview-type questions online are:
It is a good idea to spend at least 3-4 hours a week practicing live coding questions in the months preceding a coding interview. However, if you haven’t been solving problems and your interview is coming up soon, don’t worry, you can still make it. Just try to solve as many live coding interview questions as you can prior to the live coding assessment and you will be good to go.
Can You Google during Coding Interview?
Some interviewers allow looking up specific syntax or functions as it is easy to forget those if you aren’t using them everyday. Others will tell you not to.
The best way to go here is to communicate with the interviewer and tell them that you aren’t sure about how to write a specific piece of code and ask whether it’s okay to Google it.
They will either tell you the answer themselves, allow you to Google it, or tell you not to worry about it as it is more important that you follow a logical path of writing code rather than be 100% accurate.
At the end of the day, live coding interviews are about showcasing your problem-solving abilities and showing that you have a logical approach to finding solutions. As long as you show this, it doesn’t really matter whether or not you Google some syntax, so it is often a common practice to allow candidates to look up some minor programming expressions as long as they ask for permission beforehand.
Live Coding Interview Tips
In order to be ready for an interview and do your best during the assessment, there are certain things you should keep in mind. Here are some live coding interview tips.
Before the Interview
- Practice thinking out loud (preferably with another person): This is an invaluable skill when it comes to live coding interviews as it allows you to explain your thought process as you write code. It might feel awkward at first, but it will help you immensely during your live coding assessment.
- Stress-test yourself: Many great engineers choke due to stress during live coding assessments. In order to prevent this, practice solving problems while under a bit of pressure. This could be in the form of solving live coding questions in a time-boxed environment or doing live coding interviews with your peers.
- Practice with a timer: Timing is an important factor during live coding interviews. Not only do you need to know how to solve the problem, but you also need to do it within the allotted time. Practicing with a timer will help you hone this skill, and it can also help build your confidence when facing live coding questions.
- Carefully read the job description to scavenge clues for potential questions: Live coding interviews often ask questions related to the job description. This can help you prepare for live coding assessments by familiarizing yourself with the expected skills and solutions.
- Familiarize yourself with the live coding platform: Most live coding interviews are done via an online platform, so it is important to get familiar with it beforehand. This will help you avoid any technical hiccups during the live coding assessment and ensure a smooth experience for both you and the interviewer.
- Pre-check your laptop/desktop for functioning mic and camera: To make sure that your live coding assessment goes off without a hitch, it’s important to check that your laptop/desktop has a functioning microphone and camera prior to the live coding interview. This will help you avoid any technical issues during the live coding assessment.
During the Interview
- Establish a connection with the interviewer: live coding interviews are as much about showcasing your interpersonal skills as they are about showcasing your technical abilities. Make sure to make small talk and let the interviewer know that you’re eager to solve the live coding problem.
- Understand the problem: Take a few minutes to read and understand the problem carefully before you start writing code. It is important that you understand what is being asked of you in order for your solution to be correct.
- Talk through your solution: Explain your thought process out loud as you write the code. It will help make sure that your interviewer understands what you are doing, and it can also help you think through things if you get stuck in a rut.
- Break down problems into smaller sub-problems: When faced with huge problems, try to break them down into smaller, simpler sub-problems. This will make it much easier for you to solve them.
- Think about the edge cases: Edge cases are often overlooked in live coding assessments, so it’s important to think about them. This will help you come up with a more complete solution that can handle any unexpected inputs.
- Ask questions: If something is unclear, don’t hesitate to ask questions and get clarification from your interviewer. It’s important that they understand what you are trying to do in order for the live coding assessment to be successful.
- Test your code: Once you’ve written a solution, quickly test it to make sure it works as expected. This will help you avoid any embarrassing bugs during the live coding assessment and also give you confidence that your code is correct.
Following these live coding interview tips can help you perform better during your live coding assessment and help you land the job of your dreams.
Conclusion
At the end of the day, live coding interviews are meant to help you and the recruiter get a better understanding of your technical skills.
Since live coding interviews can be quite intimidating, it’s important to prepare properly before jumping in. Doing research on what kind of questions will be asked, practicing with online coding challenges and familiarizing yourself with the live coding platform will all help you feel more confident during the interview.
With some practice and preparation, live coding interviews can be an excellent way to showcase your technical skills and land the job you want! Good luck!
Elmar Mammadov is a software developer, tech startup founder, and computer science career specialist. He is the founder of CS Careerline and a true career changer who has previously pursued careers in medicine and neuroscience.
Due to his interest in programming and years of past personal experience in coding, he decided to break into the tech industry by attending a Master’s in Computer Science for career changers at University of Pennsylvania. Elmar passionately writes and coaches about breaking into the tech industry and computer science in general.