1. Cracking the Coding Interview Advice and Strategies for Software Engineering Interviews McDowell | NIT Trichy | Feb 2012 CareerCup.com Gayle Laakmann McDowell Founder / CEO, CareerCup.com Author of The Google Resume and Cracking the Coding Interview

2. Technical Skills Behavioral Applying Process My Background Software Engineer @ GOOG, MS & Apple – 3 Years on Google Hiring Committee – Interviewed 150+ candidates Founder of CareerCup.com Author – Cracking the Coding Interview – The Google Resume McDowell | CareerCup.com

3. Technical Skills Behavioral Applying Process Slides Posted Online posted at: www.technologywoman.com Click “Speaking Engagements” McDowell | CareerCup.com

4. Technical Skills Behavioral Applying Process EvaluationStructureApplyingExperienceResumeSoft SkillsPreparationInterviewTech SkillsPreparationInterview McDowell | CareerCup.com

5. Interview Process McDowell | CareerCup.com

6. Technical Skills Behavioral Applying Process Big Company Evaluation (Coding) McDowell | CareerCup.com Testing aptitude, not knowledge

7. Technical Skills Behavioral Applying Process How You Are Judged McDowell | CareerCup.com How did you do RELATIVE to other candidates on the SAME question? How did you do RELATIVE to other candidates on the SAME question? … it’s about how quickly you solved it relative to other candidates. It’s not about how quickly you solved the problem…

8. Resumes & Application Process McDowell | CareerCup.com

9. Technical Skills Behavioral Applying Process Indians are at a disadvantage Far away – Fewer recruiting opportunities Unfamiliar – Recruiters may not understand your school, GPA, etc Language barrier / Cultural differences – Accents, grammar, accidental sexism Different / less experience – More emphasis in US on projects

10. Technical Skills Behavioral Applying Process So what to do? Get equivalent experience Translate GPA & other items Use good grammar & punctuation – On resumes, cover letters, etc – No abbreviations, no sloppiness Be careful about your assumptions – Sexism is not acceptable in the U.S. Ever.

11. Technical Skills Behavioral Applying Process Cheat Sheet for Indians (Grammar / Writing) Space after comma & period. Never before. – WRONG: “Hello.I am Gayle.” – RIGHT: “Hello. I am Gayle.” Questions need a question mark – WRONG: “Do you have one.” – RIGHT: “Do you have one?” No abbreviations – WRONG: “Ny1 dr?” – RIGHT: “Is anyone there?” Commands are rude (use a question) – WRONG: “Send it to me.” – RIGHT: “Would you mind sending it to me?”

12. Technical Skills Behavioral Applying Process Cheat Sheet for Indians (Gender / Sexism) Mr. LastName / Ms. LastName – WRONG: Ms. Gayle – RIGHT: Ms. McDowell – But “Dear Gayle” is perfectly okay in U.S. “Guy” / “Guys” is not unisex* in the U.S. – WRONG: “I need to hire a really smart CS guy.” – *Except: “you guys” and “hey guys” Don’t assume that people are male / female – (Just don’t use Mr. / Ms. in emails!) It is EXTREMELY offensive to comment on someone’s looks – But a great way to get fired / rejected

13. Technical Skills Behavioral Applying Process Cheat Sheet for Indians (Getting Experience) Build something! Make a kick-ass resume McDowell | CareerCup.com Don’t waste your summers! It’s really not that hard.

14. Technical Skills Behavioral Applying Process How We Review Resumes (U.S.) 1.Pull resume out of giant stack 2.Spot-check: company names, positions, projects, schools. 3.Skim bullets to see if you’ve written real code. McDowell | CareerCup.com Interview Reject 4.Go to next resume & whine about how many more you have left. “Glanced at,” not read. 15 – 30 seconds

15. How CS Resume Should Look (U.S.) Short (1 – 2 line bullets) 3 – 4 Projects Courses & independent Finished or unfinished 3 – 4 Projects Courses & independent Finished or unfinished List of Technical Skills Short! Cut the “fluff.” List of Technical Skills Short! Cut the “fluff.” GPA - Translated We don’t understand “first class” GPA - Translated We don’t understand “first class” One Page Only! Unless > 10 years exp. One Page Only! Unless > 10 years exp. A Real Resume Format with organized columns A Real Resume Format with organized columns Focus on Accomplishments not responsibilities Focus on Accomplishments not responsibilities Observe: No Objective! Objectives / summaries are almost always useless. Observe: No Objective! Objectives / summaries are almost always useless.

16. Behavioral Questions McDowell | CareerCup.com

17. Technical Skills Behavioral Applying Process Communication Tips Goals: – Answer the question. – Deliver a *good* answer. – Communicate well. Strategies: – Nugget First – S.A.R.: Situation, Action, Result McDowell | CareerCup.com

18. Technical Skills Behavioral Applying Process Preparing for Behavioral Qs Create Preparation Grid for Projects McDowell | CareerCup.com OS ProjectAmazon Intern. Enjoyed Hated Most Challenging Hardest Bug + Behavioral Grid [for PM & less tech. roles]

19. Technical Skills Behavioral Applying Process Structure 1: Nugget First Lead with your “thesis” / nugget – Grabs the listener’s attention – Gives them context for where you’re going. McDowell | CareerCup.com A: I’m most proud of the way I re-architected the … Q: What accomplishment are you most proud of?

20. Technical Skills Behavioral Applying Process Structure 2: S.A.R. ituation ction esult McDowell | CareerCup.com S S A A R R What was the issue? What did you do about it? What was the impact?

21. Technical Skills Interview Prep McDowell | CareerCup.com

22. Technical Skills Behavioral Applying Process How to study Study the basics – Complex algorithms generally unnecessary. Practice solving questions – Don’t memorize! – See: CtCI & CareerCup.com Push yourself! Write code on paper McDowell | CareerCup.com

23. Technical Skills Behavioral Applying Process Data Structures How to implement When to use (pros / cons) McDowell | CareerCup.com Linked ListsStacksQueues TreesTriesGraphs VectorsHeapsHashtables

24. Technical Skills Behavioral Applying Process Algorithms Implementation Space vs. Time Complexity McDowell | CareerCup.com Quick SortMerge Sort Tree Insert / FindBinary Search Breadth-First Search Depth-First Search

25. Technical Skills Behavioral Applying Process Concepts Not just a concept – know how to code! McDowell | CareerCup.com Threading System Design & Scalability Memory Management Recursion Probability + Combinatorics Bit Manipulation

26. Technical Skills Mastering the Interview McDowell | CareerCup.com

27. Technical Skills Behavioral Applying Process Technical Questions 1.Ask Questions! – Questions are more ambiguous than they appear 2.Talk out loud – Show us how you think 3.Think critically – Does your algorithm really work? What’s the space and time complexity? 4.Code slowly and methodically – It’s not a race 5.Test your code – And make CAREFUL fixes. McDowell | CareerCup.com

28. Technical Skills Behavioral Applying Process What does a “good coder” do? Be methodical. Don’t try to rush. Reasonably Bug Free – Thorough testing (and careful fixing) – Check for error conditions Clean coding – Use other functions – Good use of data structures (define own if useful) – Concise and readable McDowell | CareerCup.com

29. Technical Skills Behavioral Applying Process Types of Interview Questions McDowell | CareerCup.com Coding & AlgorithmsObject Oriented DesignSystem Design “Reverse a Linked List” “Design a Parking Lot” “Design a Web Crawler”

30. Technical Skills Behavioral Applying Process Types of Interview Questions McDowell | CareerCup.com Coding & AlgorithmsPattern MatchingSimplify & GeneralizeBase Case & Build Data Structure Brainstorm Object Oriented DesignSystem Design

31. Technical Skills Behavioral Applying Process Algorithm Qs: Pattern Matching McDowell | CareerCup.com Q: Write code to reverse the order of words in a sentence. “dogs are cute” “cute are dogs” Similar to: reverse characters in a string. “dogs are cute” “etuc era sgod” A: Reverse full string, then reverse each word. Coding & AlgorithmsPattern MatchingSimplify & GeneralizeBase Case & Build Data Structure Brainstorm Object Oriented DesignSystem Design

32. Technical Skills Behavioral Applying Process Algorithm Qs: Simplify & Generalize McDowell | CareerCup.com Coding & AlgorithmsPattern MatchingSimplify & GeneralizeBase Case & Build Data Structure Brainstorm Object Oriented DesignSystem Design Q: Design algorithm to figure out if you can build a ransom note (array of strings) from a magazine (array of strings). Simplify: what if we used characters instead of strings?  Build array of character frequencies. Generalize: how we can extend answer to words? A: Build hashtable from word to frequency.

33. Technical Skills Behavioral Applying Process Algorithm Qs: Base Case & Build McDowell | CareerCup.com Coding & AlgorithmsPattern MatchingSimplify & GeneralizeBase Case & Build Data Structure Brainstorm Object Oriented DesignSystem Design Q: Design algorithm to print subsets of set. {a, b, c}  {}, {a}, {b}, {c}, {a, b}, {a, c}, {b, c}, {a, b, c} S({})  {} S({a})  {}, {a} S({a, b})  {}, {a}, {b}, {a, b} S({a, b, c})  ? A: Build S(n) by cloning S(n-1) and adding n to the cloned sets.

34. Technical Skills Behavioral Applying Process Algorithm Qs: Data Structure Brainstorm McDowell | CareerCup.com Coding & AlgorithmsPattern MatchingSimplify & GeneralizeBase Case & Build Data Structure Brainstorm Object Oriented DesignSystem Design Q: There are 10^10 possible phone #s. Explain how you could efficiently implement assignSpecificNum(num) and assignAnyAvailableNum(). Array (sorted)? Too slow to remove num. Linked list? Too slow to find specific num. Hash table? Can’t iterate through free nums. Tree? Ah-ha! A: Store free #s in BST. Remove when taken.

35. Technical Skills Behavioral Applying Process Coding & AlgorithmsPattern MatchingSimplify & GeneralizeBase Case & Build Data Structure Brainstorm Object Oriented DesignSystem Design How To Solve Algorithm Questions McDowell | CareerCup.com Compare to similar problems. Solve first for a simplified / tweaked problem. Solve for n = 1, and build solution for n = 2. Try to apply data structure to solve problem.

36. Technical Skills Behavioral Applying Process Object Oriented Design McDowell | CareerCup.com Handle Ambiguity What about the question is ambiguous? Design the Core Objects What are the main objects in the system? Analyze Relationships How are the objects related to each other? Investigate Actions What are the main operations? Coding & AlgorithmsObject Oriented DesignSystem Design

37. Technical Skills Behavioral Applying Process Coding & AlgorithmsObject Oriented DesignSystem Design Object Oriented Design McDowell | CareerCup.com Handle Ambiguity Is it a single restaurant, or part of a chain? Design the Core Objects Guest, Party, Table, Server, Host, … Analyze Relationships Server and Host are both Employees… Investigate Actions A Party is seated at a Table by a Host… How would you design the data structures and objects for a restaurant?

38. Technical Skills Behavioral Applying Process System Design McDowell | CareerCup.com Handle Ambiguity What about the question is ambiguous? Make Believe Pretend there wasn’t so much data & solve Get Real Go back to the real problem. What breaks? Solve Problems Solve the issues you just found. Coding & AlgorithmsObject Oriented DesignSystem Design

39. Technical Skills Behavioral Applying Process System Design McDowell | CareerCup.com Handle Ambiguity Do the words need to be in a specific order? Make Believe Assume everything can fit on one machine. Get Real Must split up data across machines. Solve Problems Divide hash table by file or by keyword? Given millions of documents, find all documents which contain a list of words. Coding & AlgorithmsObject Oriented DesignSystem Design

40. Technical Skills Behavioral Applying Process Whew! All Done! McDowell | CareerCup.com This is a lot of stuff. Do I need to get everything right? Coding & AlgorithmsPattern MatchingSimplify & GeneralizeBase Case & Build Data Structure Brainstorm Object Oriented DesignSystem Design

41. Technical Skills Behavioral Applying Process This is a lot of stuff. Do I need to get everything right? McDowell | CareerCup.com Evaluation is RELATIVE, not absolute. Evaluation is RELATIVE, not absolute. … it’s about how quickly you solved it relative to other candidates. It’s not about how quickly you solved the problem…

42. Technical Skills Behavioral Applying Process So RELAX! Interviews are supposed to be hard! So RELAX! Interviews are supposed to be hard! Everyone makes mistakes. Everyone! McDowell | CareerCup.com

43. Final Thoughts McDowell | CareerCup.com

44. Technical Skills Behavioral Applying Process After Your Interview Follow-up with your recruiter – No response != rejection You have no idea how well/poorly you did. – Seriously. I know you think you do. But you don’t. Lots of randomness. – So if you fail, get up and try again. McDowell | CareerCup.com

45. Technical Skills Behavioral Applying Process Other Resources Sold Today Signed (just ask!) McDowell | CareerCup.com CareerCup.com Interview Videos iPhone App Resume Review Mock Interviews today Rs. 400 5 stars! Or, stalk me online at… twitter.com/gayle facebook.com/gayle technologywoman.com gayle@careercup.com