A Comprehensive Guide to Common Written Test Questions for Software Engineers

As a software engineer, you might be preparing for a written test during the interview process. While it's impossible to predict every question, here is a guide to some of the most common types of questions you might encounter:

1. Data Structures and Algorithms

Data structures and algorithms are the bread and butter of software engineering. Here are some typical questions:

Arrays and Strings

Reverse a string Find the longest substring without repeating characters

Linked Lists

Detect a cycle in a linked list Merge two sorted linked lists

Trees

Implement a function to traverse a binary tree in-order, pre-order, and post-order Find the height of a binary tree

Graphs

Implement depth-first search (DFS) and breadth-first search (BFS) Find the shortest path in an unweighted graph

Sorting and Searching

Implement quicksort or mergesort Perform a binary search on a sorted array

2. System Design

System design questions help employers understand how you think about building and scaling systems. Some common scenarios include:

Design a URL shortening service Design a social media feed Design a file storage system like Google Drive

3. Database and SQL

Questions in this category focus on your ability to write and query databases effectively:

Write SQL queries to retrieve data from multiple tables using joins Explain normalization and denormalization

4. Concurrency and Multithreading

Concurrency and multithreading are crucial for scalable applications. Common questions include:

Explain the producer-consumer problem Write code to implement a thread-safe singleton pattern

5. Coding Challenges

Platforms like LeetCode, HackerRank, and CodeSignal are great for practicing these types of coding challenges.

6. Behavioral Questions

While not strictly technical, these questions are important for demonstrating your problem-solving skills and team collaboration:

Explain a challenging technical problem you faced and how you solved it Describe a time when you had to work as part of a team

7. Domain-Specific Knowledge

Depending on the specific role, you may encounter questions related to:

Specific technologies like cloud platforms, frameworks, or programming languages Concepts like RESTful APIs, microservices, and DevOps practices

Tips for Preparation

Here are some tips to help you prepare for these questions:

Practice Coding: Use platforms like LeetCode, HackerRank, or CodeSignal to practice coding problems. Revise Concepts: Ensure you are clear on data structures, algorithms, and system design principles. Mock Interviews: Participate in mock interviews to get comfortable with the format and types of questions.

By focusing on these areas, you can effectively prepare for written tests in software engineering interviews.