Common Coding Interview Questions in Technical Interviews by Experience Level
For companies creating and refining software, the passport to success is strong programmers with diverse skills working on top-functioning teams. That requirement makes recruiting and hiring among your most impactful processes. Management, the HR team, and your software developers already know that is true, so it’s not surprising that lots of effort and concern go into techniques for identifying the best candidates with the right skills.
That puts high priority on identifying expertise in coding applied to debugging, system architecture, and defining the challenges of a given problem and its strongest solutions. Traditionally, the screening of candidates for every level of software development has taken the form of the technical interview. Persistent efforts have been made to formulate the most effective questions for the “coding interview.” Lists of recommended questions abound.
At Woven, we realize the importance of these questions for candidates in this competitive field. Our assessment platform offers opportunities to practice giving the most effective responses to common coding interview questions. These coding interview questions with solutions are not exactly the ones asked in any given interview, but they suggest the kind of knowledge that interviewers are seeking and how they attempt to get it.
We are convinced, too, that the classic technical interview fails to provide concrete, objective evidence of coding skills in debugging, architecture, and development. Our innovative coding challenges enable candidates to demonstrate technical skills, thinking, and imagination on tests customized for the position. Candidates can find samples of coding challenge questions on our website, and these must do coding questions topic wise make it easy to focus on the most relevant areas.
Coding interview questions practice
Because many technical interviews focus on coding in a particular programming language such as Java, C#, or Python, to name some common examples, candidates can practice answering questions and solving problems in each of these languages and receive feedback on their performance.
Java is a programming language and computer platform that came from Sun Microsystems in 1995. There are many apps and websites out there today that work only with Java installed. And more and more are created all the time because Java is fast and secure. You will encounter the language in laptops, game consoles, supercomputers, and cellphones. It is nearly universal in its applications. We will look at Java coding interview questions below.
C# (C sharp) is an object-oriented programming language created by Microsoft. It is used with the NET framework—developed by Microsoft to run on Windows—to create websites, applications, and games. C# is especially popular for building gaming apps because it has features like automatic garbage collection to free up memory.
Python is another high-level programming language for general purposes. Its code is designed to be highly readable with features such as setting off blocks of language with significant indentations. And, its language constructs and object-oriented approach are said to promote clear, logical code at all scales of projects. Python was released in 1991 and then again in 2000 with major updates. We will look at python interview coding exercises below as well.
Java programming interview questions
Java and a multitude of other websites offer lists of the “most common,” “top 100,” and “most popular” Java technical interview questions. Here are a half-dozen questions from one of these top lists.
- Can you reverse a String in java? Can you write a program without using any java inbuilt methods?
- Write a java program to check if two Strings are anagram in java.
- Write a program to check if String has all unique characters in java.
- How to check if one String is rotation of another String in java
- How to find duplicate characters in String in java
- Find first non-repeated character in String in java
Notice that questions in this list are by topic, the first topic beginning with questions about a Java String. Questions also are divided into Java coding questions for beginners, Java interview questions for experienced programmers, and so on. Here are examples of programing interview questions in Java for beginners:
- What are the main features of Java? (Multiple choice answers)
- What are the fundamental principles of object-oriented programming? (Multiple choice)
- What do you mean by inheritance in java? (Brief description by candidate)
- What is constructor overloading and its use? (Brief description)
- What is polymorphism in java? (Brief description)
- What is the method overloading in java? (Brief description)
How about typical questions for experienced Java professionals? Here are a half-dozen examples. Notice that the questions all call upon the job candidate to not just choose an answer but to formulate a description of a complex Java concept.
- What is JCA in Java? (Java Cryptography Architecture for security functions)
- What is JPA in Java? (Java Persistence Applications Programming Interface to access databases in Java applications)
- What is JMS in Java? (Java Message Service for communications interface)
- What is a Chained Exception in Java? (A first exception causes another exception to execute in a program)
- State the differences between JAR and WAR files in Java. (For example, JAR files put Java classes in a library; WAR files put them in the directory of the web application)
- What is the dynamic method dispatch in Java? (An overridden method is resolved during runtime not when the program is being compiled)
Programming interview questions C#
Despite some C# tricky programming questions, C# is considered easier to learn and use than other programming languages. There are loads of C# coding exercises, C# scenario-based interview questions, and C# real time interview questions out there. Here are some basic C# interview questions:
- How is C# different from C? (For example, C# is a more object-oriented language)
- What is Common Language Runtime (CLR)? (CLR handles program executions for C# and other languages)
- What is garbage collection in C#? (A process of freeing up memory that has been tied up in unwanted objects)
- What are the types of classes in C#? (One, for example, is “Static class”)
- What is a managed and unmanaged code? (An unmanaged code is directly executed by the operating system)
- What is the difference between an abstract class and an interface? (For example, abstract classes cannot create an object)
Coding interview questions in Python
For a final example of coding interview questions based upon a specific language, you could look up a Python programming interview questions and answers pdf. Or, you could check out the six common coding questions in Python below.
- What is Python? (A “high-level, interpreted, general purpose programming language)
- What are the benefits of using Python? (It is a general purpose programming language with simple syntax and emphasizes readability. It can be used to build almost any app)
- What is a dynamically typed language? (“Typing” in programming languages means type-checking. Python languages are strongly typed, so checking types is done during execution of the language on the fly)
- What is an interpreted language? (A language that executes its statements line by line so that programs run directly from the source code)
- What is PEP8, and why is it important? (A Python Enhancement Proposal is a document that provides information to the community of Python users, say, describing a new feature. PEP8 was an important document on style guidelines for Python code)
- How is memory managed in Python? (By the Python Memory Manager, which allocates memory as a “private heap space” in which all objects are stored)
Perhaps because it is viewed as a programming language especially suitable for beginners, this Python coding interview cheat sheet offers a list of coding questions for beginners in Python. You’ll also find some real-time Python interview questions and answers set up on screens.
What about tricky programming questions? For example, many job applications suggest that because Java is a popular programming language with many seeking positions in that field, Java uses tricky questions to eliminate candidates. Here are a few examples that, depending upon your level of expertise in Java, you may or may not view as trick:
Q: How does Garbage Collection prevent a Java application from going out of memory?
A: Java Garbage Collector does not prevent a Java application from going out of memory. It simply cleans the unused memory when an object is out of scope and no longer needed. As a result, garbage collection is not guaranteed to prevent a Java app from going out of memory.
Q: Is Java “pass-by-reference” or “pass-by-value”?
A: Java is always “pass-by-value.” However, when we pass the value of an object, we pass the reference to it because the variables store the object reference, not the object itself. But this isn’t “pass-by-reference.” This could be confusing for beginners.
Q: Is it possible to override or overload a static method in Java?
A: It’s possible to overload static Java methods, but it’s not possible to override them. You can write another static method with the same signature in the subclass, but it’s not going to override the superclass method. It’s called method hiding in Java.
Beyond the technical interview: the Woven coding challenge
The impressive ingenuity and effort that for decades has gone into formulating coding questions and other programming and debugging questions continues today. The questions today may be on a computer, not paper, but the method is the same: seeking information about applicant technical skills, particularly coding, by asking the applicant about it.
In this context, Woven’s approach to the technical interview represents a real departure. By asking job candidates for software engineering roles to define and solve real problems, and to do so by writing code, your engineering team can get a real-time demonstration of coding skills, approaches to problems, and effectiveness of solutions. The evidence is objective and relevant to the day-to-day demands of the job being filled. When our engineering staff scores and interprets the results of the test, we compare candidates on the same test and make specific recommendations.
At the same time, candidates benefit because our Engineer Evaluation Engine provides them with feedback on their performance compared to other candidates.
Woven’s coding challenges address abilities common to software engineers at all levels: debugging, technical communication, systems theory, backend programming, and frontend programming. However, these common challenges are tested at different levels of experience appropriate in specific roles such as Junior/Mid Fullstack Engineer, Mid/Senior Frontend Engineer, and Engineering Manager.
If you are ready to talk about adding customized Woven coding challenges to your interview and selection process, our sales team will begin by understanding your hiring priorities and processes to identify or create the right test for roles you seek to fill. We can discuss how coding challenges can save time in the hiring process and help you grow your team. Begin by starting your free trial where you can take a work simulation and see actual results!