As a Python coder, you’ll want to use and excel at Python during coding interviews. So the best question will be how to prepare for a python coding interview.
You may be a fantastic Python developer, but coding interviews are not about the day-to-day job. Instead, they are about exploring your knowledge, understanding, and skills during tight timelines.
Below are some specific tips at Algo.Monster to properly prepare for a python coding interview and get your next job.
Python has a minimal number of built-in functions that can you can use by default. Ensure you go through each one and understand when it would be best to use each of them or better alternatives.
Instead of importing a library or writing something yourself, make sure you show knowledge of Python by using built-in functions.
Many developers will check coding issues by adding a print() to the output. This function gives you a quick idea of what is the code is outputting. However, this can become a problem for more extensive programs and more significant debugging tasks.
During a coding interview, you want to write clean code and put your best foot forward on how you debug problems.
Use a real debugger instead. By default, breakpoint() will drop you into the included Python debugger.
Take time to study, learn, and see the best way to debug using breakpoint(). This default debugger is a good option during coding interviews as Python includes it by default. So it will always be available, unlike some other debuggers.
During coding interviews, an extremely common topic is where you have a list that you must iterate over while still having access to the values and indices.
Many developers will use range() to do this. However, the better solution during a Python-specific coding interview is to use enumerate() to simultaneously access both the value and index for each item.
It’s another example of using the correct built-in function for the job required. It’s not simply good enough to get the job done; you should be doing it with precision.
You can format strings in several ways. However, the preferred method for Python and to give you extra points during the coding interview should be f-Strings. f-Strings provide a more precise output with better functionality included. It’s also another built-in function to show your understanding of Python and to speed up your code.
You can also use Template Strings when you need to handle user input due to security issues. If you were to bring this differentiation up, you would really get points for understanding Python and the security aspects of systems.
Security is a significant component when building systems that have user interaction. Security flaws built into a system can harm the company’s profile and potentially disclose sensitive customer data or the company’s internal workings. So showing a good understanding of this can only benefit you and your chances of getting the job.
Data structures are often a significant component in most coding interviews. During a coding interview, you need to be writing the most efficient code possible. You should be picking the correct data structure for your specific task, which will have a massive impact on the performance of your program.
It’s also beneficial to explain your understanding of data structures and why you’re using a specific one to gain superior performance.
Python has excellent standard data structure implementations build-in. These data structures are another example of using built-in functionality to show your understanding of your programming language. It also makes things much quicker during a short coding interview.
- Use set to store unique values
Removing duplicates is a common task and using sets from the start is the optimal Python way.
- Use generators to save memory
Using lists can often be convenient but can lead to significant memory waste.
- Use default values in dictionaries
To speed up code and make it more efficient, you can get and set values using setDefault()
Python has an extremely powerful default library that you can use and know will always be available. Reviewing and knowing what is available from the default library can improve your code, show your understanding of Python and make writing the code a lot quicker.
Speed is one of the main contributors to developers failing the coding interview, so whatever you can do to make things faster will benefit you.
Some common and useful libraries to review and understand when to use are:
- Deal with missing dictionary keys using collections.defaultdict()
- Use collections.Counter to count hashable objects
- Consider string constants to access common string groups
- Use itertools to generate combinations and permutations
A Python coding interview will heavily test your knowledge of Python and not just the code you can write. Therefore, you need a thorough understanding of Python best practices. In addition, you need to know all of the built-in features available in Python so that you can wow your interviewer with your knowledge.
Rewriting code or using external libraries when a built-in option is available in Python just shows your lack of understanding of the programming language you should now. Not using built-in options shows the developer you may not know Python well enough to write the cleanest, most efficient code.
To review specifics, make sure you go over the following:
- Python built-in functions
- Standard data structures in Python to simplify your code
- Standard libraries are available by default, allowing you to write more straightforward and more efficient code.
Coding interviews are not about if you can code, they are about how you code, if you understand your programming language and if you write clean, efficient, and fast code.
Anything you are doing that Python can already do by default will likely be a mark against you in the coding interview.