How to Pass an Interview for a Software Engineer?

1. How to Pass an Interview for a Software Engineer? What to Do and What to Avoid? Svetlin Nakov Technical Trainer www.nakov.com Software University http://softuni.bg JobInterview

2. Table of Contents • What is a Job Interview? • Preparation for an Interview • Typical Interview Questions andAnswers for Software Engineers • Classical Questions • Technical Questions • Non-Technical (Personality) Questions • Questions to Ask • Typical Mistakes and How to Avoid Them?

3. What is a Job Interview? A Stressful Situation or a Chance to Demonstrate Your Knowledge and Skills?

4. What is a Job Interview? • A job interview is a formal meeting: candidate vs. employer • Aimed to assess a candidate for a certain job position • The candidate should convince he or she is the right person for the offered position • The interviewers assess the skills and personality • By questions and small tasks • The candidate tries to prove his or her skills • The candidate demonstrates his or her personal character

5. How to Overcome the Stress? • The job interview is a stressful situation! • You need to present yourself in the best way • Many candidates fail to demonstrate their skills due to stress • How to overcome the stress? • Just be well prepared! • Prepare yourself for the technicaland non-technical questions • Expect the questions and have good answers • Practice going to interviews

6. Interview Preparation What is the Best Way to Prepare Yourself for an Upcoming Interview?

7. Steps to Prepare for an Interview • Once you have scheduled and interview • Put enough effort in your interview preparation • Half an hour is not enough, invest a few days • Steps to prepare for an interview • Research the company and the HRs • Research the offered position • Prepare for technical questions • Prepare for personality questions

8. Research the Company • Always research the company you apply for • You should expect a question at the interview like "What do you know about our company?" • If you answer "Nothing", you will fail • If you say something incorrect, it is even worse • How to find information? • Explore the company Web site, brochures, publications, ads, etc. • Look for articles, blogs, forums, etc. • Ask your friends what do they know

9. Research the Company (2) • What information you should know? • The company products / services portfolio • Download the company's products and play with them • The target market and customers • The technologies used in the development • E.g. PHP, JavaScript, Angular.js, MySQL, jQuery, etc. • The company mission, vision, projects, etc. • The corporate culture, corporate values

10. Research the Offered Position • Research the offered position, requirements, advantages and responsibilities • You should research all mentioned products, services and technologies in the job description • E.g. if you see "Experience with Selenium is a plus", be sure to install and play with Selenium • Be sure to know all "unknown words and acronyms" in the job description • Be ready to demonstrate skills and experience in the fields from the job description

11. Prepare for Technical Questions • How to prepare for the technical questions? • Typical general technical questions • Data structures and algorithms • Logical thinking and puzzles • Software engineering questions • Object-oriented programming (OOP) • Specific questions for the offered position • If the job description says "JSF and RichFaces", you should learn these technologies

12. Prepare for Technical Questions (2) • How do you prepare for a certain technology? • Pass a course / tutorial / read a book / blog articleabout the unknown technology • Obligatory create a small project usingthe technology and play with it • This is the only way to get somereal-life experience, live in a project • If you have never used a certain technology (e.g. JSF) you cannot say you are prepared • The best way to learn it is by practicing

13. The Interview Process Typical Scenario for a Technical Interview

14. Technical Interview: The Process • Typical interview steps for a technical position: • The candidate presents himself or herself • The interviewers present the company, its business, products, services, etc. • Technical assessment – solve few technical problems and demonstrate the way of thinking • Personal character assessment • Negotiation – salary expectations, start date, etc. • The candidate asks questions

15. Presenting the Company / Position My name is … Our company is … bala-bla-bla … We are leader in … bla-bla-bla … Our products bla-bla-bla … Our projects … bla-bla-bla … We are the best! • Typical interview start: • The interviewers presents themselves • Usually there is more than one interviewer • HR (or HRs) and senior devs and / or team leaders • The interviewer presents in short the company, his department, his team, current / upcoming projects, technologies involved, etc. • Some companies skip this step, expect the candidate to know this

16. Presenting Yourself Present yourself in short – your relevant experience, education, how did you start programming, etc. • Typical next step in an interview: • The candidate is expected to say few words about himself / herself • Be prepared to talk 3-5 minutes • Explain how did you start programming • Your last job and projects (if you have) • Your current occupation (e.g. student at SoftUni / FMI / NBU) • How did you learn about the position and your motivation to apply

17. Technical Assessment • The technical assessment is critical for passing the interview • You will be given technical questions to answer • And small technical problems to solve • Always come with a pen and writing pad • It is not so important whether you solve correctly the tasks or answer correctly • You should demonstrate your way of thinking! • The interviewer wants to know how you attack the problem, not whether the result is correct

18. Technical Questions – Examples In C# which explain the fastest algorithm to sort a list of customers by their first name? … I know the build-in Array.Sort() method, but I am not sure if it is the fastest. If I had a computer I would perform a Google search. For multi-core CPUs I could try the parallel sorting using parallel LINQ. I should you a Customer class and either implement own comparer or use a lambda function to sort by the FirstName property. • You should demonstrate your way of thinking • By saying what you think at the moment, e.g. • Being silent for a minute while you think is evil!

19. Technical Problem – Example How do you can shuffle a deck of playing cards? • Suppose you are given a simple problem like: • The first thing to do is to get the writing pad and draw an example! • This shows a correct and serious way of thinking • By using the pen explain how you could shuffle the cards • Explain how you will represent a single card and a deck of cards (data structures) • Explain how you could test your solution

20. Personal Character Assessment Do you have experience working in a team? What do you prefer – being a leader or a player? Do you play some kind of sport? At what position? How do you react if you are about to miss a deadline? • Assessment of your personal character qualities is very important for the company! • Good software companies will weight your personal skills more than your technical skills • You will be asked irrelevant questions that reveal your character

21. Personal Character Assessment (2) • At the personal assessment questions there is no correct or wrong answer • Just be yourself • Don't recite some other's words • Very important: be positive! • Negative people are not welcome anywhere • Be confident • Avoid saying "I don't know" • Demonstrate willingness and ability to work in a team

22. Negotiation • If your interview runs well, you will reach the "negotiation" part • Salary expectations – always have a good answer • Eventual start date • Other terms of the contract: bonuses, holidays, working time, etc. • Companies don't like "money-driven" employees • You should demonstrate motivation to work hard for long-term and continuously improve your skills • Money should not be the primary focus for your first job

23. Your Questions • Finally you will have a chance to ask your questions • Having no questions is not good • Demonstrate interest to start working • Ask about your first project, about the development process, about your team, etc. • Avoid asking about salary raises, bonuses, parking space, fitness and sport facilities, etc. • You should demonstrate motivation to work hard, not claims

24. Typical InterviewQuestions and Answers (for Junior Software Development Positions)

25. Typical Interview Questions Categories • At a technical interview you will be given questions from several categories: • General questions • Technical questions • Abstract thinking questions • Personal character questions • The "salary" question

26. General Questions Experience, Education, Future Plans

27. Typical General Questions Where are you from? What High school have you graduated? What University have you graduated / studying now? When you started programming? How many books about computer programming you have read? What was the name of the last? Do you believe that computer programming is your passion and your future job? Can you work on full time (8 hours/day)? If not how many hours a week you can work?

28. Typical General Questions (2) What do you know about our company? What are your English skills? Can you freely talk on the telephone in English? What are your plans for the next few years? How you see your career after 2 or 3 years? How you inform yourself about new technologies? Do you read news or blogs? Which sites? Shall you study more after you graduate your current University degree? Maybe abroad? How will you describe your typical work day?

29. Your Last Employer • Why did you leave your last employer? • Be positive, be mild, avoid hating • Never say "they were fools, idiots, stupid, …" • Explain that you are looking for a better career • If you hate your former employer, you will hate your next employer too • Companies don't like haters

30. Technical Questions Algorithms, Databases, Web Technologies, Etc.

31. Typical Technical Questions Can you draw a picture of a linked list? What is typical for the Strings in C# / Java / PHP? Explain how polymoprhism works in the object-oriented programming. Explain what is a hash-table and how it works. Explain how the QuickSort works. How fast is it? You are given a set of words. Find all their subsets. You have to implement a Web spider which runs on a cluster of machines. How you will design it? Algorithms, data structures, OOP:

32. Typical Technical Questions (2) How we implement one-to-many and many-to-many relationship in relational databases? When we use "1 x 1" relationships in database modelling? Give an example. What is database constraint? How constraints work? You have a table consisting of: EmployeeId (PK), Name, Salary, ManagerId (FK), DeptId (FK). Write a SQL query to find the name, salary and department of the employee that has minimal salary in his/her department. If many employees take the minimal salary, display just one of them. What is typical for the NoSQL databases? Give examples. Databases and SQL:

33. Typical Technical Questions (3) Explain the difference between HTTP GET and POST requests. Explain the meaning of the following CSS rule: .newscolumn { width: 400px; float: left; clear: both; } We have a <div> element in a HTML page which is visible. How to hide the <div> with JavaScript? How to do the above in jQuery? Web development questions (front-end):

34. Typical Technical Questions (3) How do you implement a HTML form with variable number of fields (with [Add row] / [Remove row] functionaliry)? How will you create a responsive Web site of 4 columns, which shrinks to 2 columns and 1 column on smaller devices? Explain how SASS works. Explain what is a "closure" in JavaScript. How do you color the odd / even table rows in a HTML table? Web development questions (front-end):

35. Typical Technical Questions (4) How you could implement a shopping cart in PHP / ASP.NET / Java? What is a custom tag / user control in a ASP.NET / Java / PHP based Web application? How it works? When we need this technology? What is AJAX and how it works? How we use AJAX in ASP.NET / jQuery / PHP / Java based Web application? We have a list of products that have name, price and photo. We need to display them in a Web application. Describe the steps to do this in ASP.NET / Java / PHP. How we implement URL rewriting in PHP / ASP.NET / Java Web app? Web development questions (server side):

36. Typical Technical Questions (5) What is the difference between DOM, SAX and StAX parsers for XML? How do you use DOM in C# / Java / PHP? What is XPath and how it works? Give an example. How you use XPath in C# / Java / PHP? How we execute multiple tasks in the same time in C#? You have to download 500 files from Internet but your network bandwidth is not too wide to handle 500 downloads simultaneously so you want to download the files by 10 at a time. How to do this? XML questions: Multithreading questions:

37. Typical Technical Questions (6) What is software requirements specification (SRS)? What is the typical structure of such document? What is source control repository? Which source control software you have used and when? What is unit testing? When we need it? What unit testing frameworks you have used? How the "continous integration" works? Explain what is agile development. What is Scrum? Explain the most important practices of Scrum. Software engineering questions:

38. Abstract Thinking Questions Puzzles, Unsolvable Problems, Etc.

39. Abstract Thinking Questions Estimate how many gas stations exist in Sofia. Do you see the tree outside on the street? Can you calculate how many leaves it has? You have 8 balls. One of them is defective and weighs less than others. You have a balance to measure balls against each other. In 2 weighings how do you find the defective one? • Questions in the category "abstract thinking" aim to check your ability to think and to attack unsolvable problems • Sometime no correct answer exist • Your task is to demonstrate your thinking

40. Personal Character Questions Your Best and Worst Qualities, Ability to Work in a Team, Handling a Stressful Situation

41. Personal Character Questions Describe the ideal software company from your dreams. Can you describe an ideal collague / team member? What are your 5 best personal character qualities? What are your 5 worst personal character qualities? What kind of sport do you practice? At which position do you play? What shall you do if you have a deadline until tomorrow and your project is not completed? How do you resolve a conflict with a colleague? Questions to assess your personal character:

42. Personal Character Questions (2) Do you prefer to work independently or in a team? Give some examples of a team work from your experience. What does motivate you and what does not? How do you handle stress and pressure? Describe a difficult work situation / project you have experienced and how you overcame it. How you can evaluate your results. What is success? Questions to assess your personal character:

43. Personal Character Questions (3) What were your responsibilities at your last job / last project? What major challenges and problems did you face? How did you handle them? Why are you leaving your current job? What interests you about this job? What challenges are you looking for in this position? Why we need to hire you, not someone else? Questions to assess your personal character:

44. The "Salary" Question How to Answer in the Best Way?

45. The "Salary" Question What salary do you expect? I don't care about the payment. I want to work at the company for long-term and I believe that if my results are good I will be paid accordingly. I understand that I have to learn a lot. Thus now I think I could start with a salary of XXX leva and in a year I expect to become more skillful and get a pay rise of YYY (or be fired if I don't meet your expectations). • The typical salary question is like this? • Demonstrate that your work is more important than the payment • Examples of possible answers:

46. The "Salary" Question (2) I don't know what salary to expect. Please make an offer for me. You will be a junior developer (trainee). For this position our salary range is from XXX to YYY leva. You always talk about a net salary (after all the taxes are deducted) for a full-time job (8 hours) Some candidates will say: Some companies have a policy for this case: Most companies will force you to say a certain number and you should say something – be ready!

47. The "Salary" Question (3) • Typical net salary ranges (Sofia, September 2014) for full-time software engineer jobs: • Trainee – 500-800 lv. • Junior front-end / Web site developer – 700-1000leva • Junior PHP developer – 700-1100 leva • Junior .NET / Java / JS / mobile developer – 800-1200leva • Junior QA engineer – 500-1000leva • Junior support officer – 500-800leva • After a 1-2years you could expect twice

48. Typical Mistakes One Wrong Word Could Spoil the Deal!

49. Typical Mistakes Did you have colleagues or classmates who you can't stand? What were they? Why you can't stand them? Generally I can stand anyone. I don't like too much XXX kind of people but if I need to work in a team with such colleagues I will defenitely find a way. • Don't hate your former employers, colleagues, etc. • Always be positive! • Typical "catch-you" question • Possible nice answer:

50. Typical Mistakes • Generally all kinds of inadequate claims or pretentions are evil • Requesting too high salary, too high position, too short work-time (less than 8 hours / day) • Being negative about something or someone • Be positive, be successful, be skillful, be professional, don't blame somebody else! • You should demonstrate motivation to work hard for long-term • Anything confirming the opposite is harmful