Ce diaporama a bien été signalé.
Nous utilisons votre profil LinkedIn et vos données d’activité pour vous proposer des publicités personnalisées et pertinentes. Vous pouvez changer vos préférences de publicités à tout moment.
GayleL.McDowell | Founder/ CEO
gayle in/gaylemcdgayle
Cracking the Facebook
Coding Interview
I <3 Facebook!
CareerCup
Why am I here?
00
gayle in/gaylemcdgayleGayle Laakmann McDowell 3
Why wouldFacebookprepyou?!?
Be more
comfortable
Be more prepared
Take out
...
gayle in/gaylemcdgayleGayle Laakmann McDowell 4
Hi! I’m Gayle LaakmannMcDowell
Author Interview Coach Interview Consulting...
Gayle Laakmann McDowell 5gayle in/gaylemcdgayle
Yes! Slidesare online!
Gayle.com
 Click “Events”
 Ctrl-F for “Facebook”
What to Expect
gayle in/gaylemcdgayleGayle Laakmann McDowell 7
A Typical**Process(**notuniversal!Askyourrecruiter)
Phone Onsite HiringCom...
gayle in/gaylemcdgayle 8
z
Gayle Laakmann McDowell
Typical
Coding
Interview
5 Minutes
Questions FORInterviewer
35 Minutes
...
gayle in/gaylemcdgayle 9
z
Gayle Laakmann McDowell
Typical
Design
Interview
5 Minutes
Questions FORInterviewer
35 Minutes
...
Behavioral
Questions
The soft squishy stuff.
02
gayle in/gaylemcdgayleGayle Laakmann McDowell 11
The Pitch /Resume Walk-Through
• Showsof success
• Prompt the
interviewer...
Gayle Laakmann McDowell 12gayle in/gaylemcdgayle
Your Past Work
3+ Projects
 Hard / cool
 You werecentral
 Technical d...
gayle in/gaylemcdgayle 13
z
Gayle Laakmann McDowell
What
about
YOU?
Be PASSIONATE
Be KNOWLEDGEABLE
Be a GOOD TEAMMATE
Design Questions
Big, meaty problems
03
gayle in/gaylemcdgayle 15
z
Gayle Laakmann McDowell
How
To
Approach
W
W
Y
D
A
W
hat
ould
ou
o
t
ork
gayle in/gaylemcdgayle 16
z
Gayle Laakmann McDowell
How
To
Approach
S
K
I
R
cope
eycomponents
dentify issues
epair
gayle in/gaylemcdgayle 17
z
Gayle Laakmann McDowell
How
To
Approach
① Scope the Problem
 Askquestions
 Make appropriatea...
Gayle Laakmann McDowell 18gayle in/gaylemcdgayle
ExampleQuestion
Gayle Laakmann McDowell 19gayle in/gaylemcdgayle
Design sketch
Frontend
Backend
Data store
logger
Gayle Laakmann McDowell 20gayle in/gaylemcdgayle
Collaborativediscussionthat you’re driving!
DRIVE
 Leadtheprocess
 Be ...
gayle in/gaylemcdgayle 21
z
Gayle Laakmann McDowell
How
To
Prepare
Read about design of major companies
 THINK, don’t me...
Algorithm
Questions
Things that make you think
04
Gayle Laakmann McDowell 23gayle in/gaylemcdgayle
Why?
Analytical skills
How you think
Make tradeoffs
Pushthrough hard
...
gayle in/gaylemcdgayleGayle Laakmann McDowell 24
Essential Knowledge
Data Structures Algorithms Concepts
ArrayLists Merge ...
gayle in/gaylemcdgayleGayle Laakmann McDowell 25
Preparation
MASTER Big O
ImplementDS/Algorithms
Practicewith interview...
A Crash Course in Big O
Just getting your feet wet
gayle in/gaylemcdgayleGayle Laakmann McDowell 27
Basicfor loop
Print0 throughN
Runtime?
 O(N)
gayle in/gaylemcdgayleGayle Laakmann McDowell 28
Two loops
Printevens, thenodds
Runtime?O(N)
gayle in/gaylemcdgayleGayle Laakmann McDowell 29
Basicfor loop
Printpairs from two arrays
Runtime?
 O(A*B)
gayle in/gaylemcdgayleGayle Laakmann McDowell 30
Basicfor loop
Printordered pairs
Runtime?
 O(N2)
j : 0  N
i:0N
x x x...
gayle in/gaylemcdgayleGayle Laakmann McDowell 31
Okay now thingsare getting tougher!
gayle in/gaylemcdgayleGayle Laakmann McDowell 32
Okay now thingsare getting tougher!
Step 1: O(P)
 P = numberof people
...
gayle in/gaylemcdgayleGayle Laakmann McDowell 33
Validate
Validate
Runtime?
 undefined
gayle in/gaylemcdgayleGayle Laakmann McDowell 34
Fibonacci
Runtime?
Eeek. Recursion?
gayle in/gaylemcdgayleGayle Laakmann McDowell 35
Fibonacci
Eeek. Recursion?
• Height of N
• Each level doubles # nodes
• ...
gayle in/gaylemcdgayleGayle Laakmann McDowell 36
Fibonacci, part 2
Runtime?
Eeek. Recursion?
• Height of N
• Each level ...
gayle in/gaylemcdgayleGayle Laakmann McDowell 37
Reminders
Drop constants
Don’t drop non-constants
Differentvariables
...
Solving Algorithms
How to… attempt to solve a hard problem
gayle in/gaylemcdgayle 39
z
Gayle Laakmann McDowell
What
is NOT
expected
To know the answers
To solve immediately
To co...
gayle in/gaylemcdgayle 40
z
Gayle Laakmann McDowell
What
IS
expected
Be excitedabout hard problems
Drive!
 Keep trying ...
gayle in/gaylemcdgayle 41
z
Gayle Laakmann McDowell
How
To
Approach
CrackingTheCodingInterview.com“Resources”
gayle in/gaylemcdgayle 42Gayle Laakmann McDowell
step
Listen (for clues)
Gayle Laakmann McDowell 43gayle in/gaylemcdgayle
What’s the clue?
Anagram server
 Ex: rates ->aster, stare, taser, tears...
gayle in/gaylemcdgayle 44Gayle Laakmann McDowell
step
Draw an Example
INTERSECTION SIZE: Find #
elementsin common between...
gayle in/gaylemcdgayleGayle Laakmann McDowell 45
Ex:Intersection ofTwo Sorted Arrays
Most people draw somethinglike this:...
gayle in/gaylemcdgayleGayle Laakmann McDowell 46
Ex:Intersection ofTwo Sorted Arrays
Better:
[1, 12, 15, 19, 20, 21]
[2, ...
gayle in/gaylemcdgayle 47Gayle Laakmann McDowell
step
Draw an Example
Big Enough
General Purpose
+
gayle in/gaylemcdgayle 48Gayle Laakmann McDowell
step
Brute Force / Naive
Stupid&terribleisokay!
gayle in/gaylemcdgayle 49Gayle Laakmann McDowell
step
Optimize
Walk through brute
force
Look for optimizations
Gayle Laakmann McDowell 50gayle in/gaylemcdgayle
Techniquesto Develop Algorithms
BUD
Space and Time
Do It Yourself
Rec...
Gayle Laakmann McDowell 51gayle in/gaylemcdgayle
(A) Look for BUD
Bottlenecks
Unnecessary work
Duplicated work
Gayle Laakmann McDowell 52gayle in/gaylemcdgayle
What’s the bottleneck?
 Ex: countingthe intersection
[1, 12, 15, 19, 20,...
Gayle Laakmann McDowell 53gayle in/gaylemcdgayle
What’s unnecessary?
 Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000
 Unnec...
Gayle Laakmann McDowell 54gayle in/gaylemcdgayle
What’s unnecessary?
 Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000
 Unnec...
Gayle Laakmann McDowell 55gayle in/gaylemcdgayle
What’s duplicated?
 Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000
 Duplic...
Gayle Laakmann McDowell 56gayle in/gaylemcdgayle
What’s duplicated?
 Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000
 Duplic...
Gayle Laakmann McDowell 57gayle in/gaylemcdgayle
What’s duplicated?
 Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000
 Duplic...
Gayle Laakmann McDowell 58gayle in/gaylemcdgayle
What’s duplicated?
 Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000
D
Gayle Laakmann McDowell 59gayle in/gaylemcdgayle
What’s duplicated?
 Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000
D
Gayle Laakmann McDowell 60gayle in/gaylemcdgayle
(B)Space/TimeTradeoffs
Hashtables & other datastructures
Precomputing
Gayle Laakmann McDowell 61gayle in/gaylemcdgayle
(C)Do it yourself
Findpermutationsof swithinb
gayle in/gaylemcdgayleGayle Laakmann McDowell 62
find abbcd in
b a b c d b a e f d b b a c b d d f a e
0 1 2 3 4 5 6 7 8 9...
Gayle Laakmann McDowell 63gayle in/gaylemcdgayle
(C)Do it yourself
Findpermutationsof swithinb
 s = abbcd
 b =
Findthe...
Gayle Laakmann McDowell 64gayle in/gaylemcdgayle
(D)Recursion
 Use, but don’t cling to, recursion
“instinct”
 Trybottom-...
Gayle Laakmann McDowell 65gayle in/gaylemcdgayle
Techniquesto Develop Algorithms
BUD
Space and Time
Do It Yourself
Rec...
gayle in/gaylemcdgayle 66Gayle Laakmann McDowell
step
Walk Through
Know the variables
andwhen they change
gayle in/gaylemcdgayle 67Gayle Laakmann McDowell
step
Write Beautiful Code
Gayle Laakmann McDowell 68gayle in/gaylemcdgayle
How toWrite WhiteboardCode
Write straight
Top-leftcorner
Use arrows if...
Gayle Laakmann McDowell 69gayle in/gaylemcdgayle
Error Cases
Good to check errors / boundaries!
But consider the time…
gayle in/gaylemcdgayleGayle Laakmann McDowell 70
Good Style
Spacing, line breaks, variable names
Gayle Laakmann McDowell 71gayle in/gaylemcdgayle
Language Choice
Java, Objective C, etc:Abbreviate
Python, Ruby, JS,etc:...
gayle in/gaylemcdgayleGayle Laakmann McDowell 72
Modularization
Gayle Laakmann McDowell 73gayle in/gaylemcdgayle
Modularize(Upfront!)
I’ve learned
nothing.
gayle in/gaylemcdgayle 74Gayle Laakmann McDowell
step
Testing
FIRST Analyze
 What’s it doing? Why?
 Anything that looks...
gayle in/gaylemcdgayle 75
z
Gayle Laakmann McDowell
How
To
Approach
CrackingTheCodingInterview.com“Resources”
Questions for Your
Interviewer
What do you want to know?
05
Gayle Laakmann McDowell 77gayle in/gaylemcdgayle
Prepare some questions
What’s made you
happy / unhappy?
What are your g...
Final Thoughts
And questions
06
gayle in/gaylemcdgayle 79
z
Gayle Laakmann McDowell
It’s done
for a
reason!
Be agreat teammate.
Be a great engineer.
Gayle Laakmann McDowell 80gayle in/gaylemcdgayle
Butwait, there’s onemore thing...
READY? Follow up with your recruiter t...
gayle in/gaylemcdgayleGayle Laakmann McDowell 81
Other Resources
Gayle.com
CareerCup.com
CrackingThe
CodingInterview.com
O...
Prochain SlideShare
Chargement dans…5
×
Prochain SlideShare
Cracking the Algorithm & Coding Interview
Suivant
Télécharger pour lire hors ligne et voir en mode plein écran

96

Partager

Télécharger pour lire hors ligne

Cracking the Facebook Coding Interview

Télécharger pour lire hors ligne

Livres associés

Gratuit avec un essai de 30 jours de Scribd

Tout voir

Cracking the Facebook Coding Interview

  1. 1. GayleL.McDowell | Founder/ CEO gayle in/gaylemcdgayle Cracking the Facebook Coding Interview I <3 Facebook! CareerCup
  2. 2. Why am I here? 00
  3. 3. gayle in/gaylemcdgayleGayle Laakmann McDowell 3 Why wouldFacebookprepyou?!? Be more comfortable Be more prepared Take out the mystery Avoid common mistakes
  4. 4. gayle in/gaylemcdgayleGayle Laakmann McDowell 4 Hi! I’m Gayle LaakmannMcDowell Author Interview Coach Interview Consulting <dev> </dev> (CS) (MBA)
  5. 5. Gayle Laakmann McDowell 5gayle in/gaylemcdgayle Yes! Slidesare online! Gayle.com  Click “Events”  Ctrl-F for “Facebook”
  6. 6. What to Expect
  7. 7. gayle in/gaylemcdgayleGayle Laakmann McDowell 7 A Typical**Process(**notuniversal!Askyourrecruiter) Phone Onsite HiringCommittee & Decision ½ Behavioral ½ Algo / Coding Design Algo / Coding Algo / Coding Algo / Coding
  8. 8. gayle in/gaylemcdgayle 8 z Gayle Laakmann McDowell Typical Coding Interview 5 Minutes Questions FORInterviewer 35 Minutes Question #1 Question#2 5 Minutes Prior Experience
  9. 9. gayle in/gaylemcdgayle 9 z Gayle Laakmann McDowell Typical Design Interview 5 Minutes Questions FORInterviewer 35 Minutes Question#1 5 Minutes Prior Experience
  10. 10. Behavioral Questions The soft squishy stuff. 02
  11. 11. gayle in/gaylemcdgayleGayle Laakmann McDowell 11 The Pitch /Resume Walk-Through • Showsof success • Prompt the interviewer • Hobbies I’masoftwareengineerat... Mybackground’sinCS. IstudiedatUPennandthen… Atmycurrentcompany,I… OutsideofworkI…
  12. 12. Gayle Laakmann McDowell 12gayle in/gaylemcdgayle Your Past Work 3+ Projects  Hard / cool  You werecentral  Technical depth All Past Work  TECHNICAL:Challenges, architecture, tradeoffs, successes, motivations  SOFT:Teamwork, leadership, conflicts, etc What did YOU do? What would you do differently?
  13. 13. gayle in/gaylemcdgayle 13 z Gayle Laakmann McDowell What about YOU? Be PASSIONATE Be KNOWLEDGEABLE Be a GOOD TEAMMATE
  14. 14. Design Questions Big, meaty problems 03
  15. 15. gayle in/gaylemcdgayle 15 z Gayle Laakmann McDowell How To Approach W W Y D A W hat ould ou o t ork
  16. 16. gayle in/gaylemcdgayle 16 z Gayle Laakmann McDowell How To Approach S K I R cope eycomponents dentify issues epair
  17. 17. gayle in/gaylemcdgayle 17 z Gayle Laakmann McDowell How To Approach ① Scope the Problem  Askquestions  Make appropriateassumptions ② Define Key Components  Can besomewhatnaïve ③ Identify Issues  Bottlenecks,tradeoffs ④ Repair & Redesign Breadth-first,notdepth-first
  18. 18. Gayle Laakmann McDowell 18gayle in/gaylemcdgayle ExampleQuestion
  19. 19. Gayle Laakmann McDowell 19gayle in/gaylemcdgayle Design sketch Frontend Backend Data store logger
  20. 20. Gayle Laakmann McDowell 20gayle in/gaylemcdgayle Collaborativediscussionthat you’re driving! DRIVE  Leadtheprocess  Be openaboutissues TEAMWORK  Be opentofeedback  Tweak asnecessary Usethewhiteboard!
  21. 21. gayle in/gaylemcdgayle 21 z Gayle Laakmann McDowell How To Prepare Read about design of major companies  THINK, don’t memorize! Know key concepts  Tasks, sharding, caches.  Web stack, REST, etc Practice back-of-the-envelope calculations
  22. 22. Algorithm Questions Things that make you think 04
  23. 23. Gayle Laakmann McDowell 23gayle in/gaylemcdgayle Why? Analytical skills How you think Make tradeoffs Pushthrough hard problems Communication Strong CS fundamentals
  24. 24. gayle in/gaylemcdgayleGayle Laakmann McDowell 24 Essential Knowledge Data Structures Algorithms Concepts ArrayLists Merge Sort BigO Time Hash Tables QuickSort BigO Space Trees(+Tries) & Graphs Breadth-FirstSearch Recursion LinkedLists Depth-FirstSearch Memoization/ Dynamic Programming Stacks/ Queues BinarySearch Heaps
  25. 25. gayle in/gaylemcdgayleGayle Laakmann McDowell 25 Preparation MASTER Big O ImplementDS/Algorithms Practicewith interview questions Code on paper/whiteboard Mock interviews PUSHYOURSELF!
  26. 26. A Crash Course in Big O Just getting your feet wet
  27. 27. gayle in/gaylemcdgayleGayle Laakmann McDowell 27 Basicfor loop Print0 throughN Runtime?  O(N)
  28. 28. gayle in/gaylemcdgayleGayle Laakmann McDowell 28 Two loops Printevens, thenodds Runtime?O(N)
  29. 29. gayle in/gaylemcdgayleGayle Laakmann McDowell 29 Basicfor loop Printpairs from two arrays Runtime?  O(A*B)
  30. 30. gayle in/gaylemcdgayleGayle Laakmann McDowell 30 Basicfor loop Printordered pairs Runtime?  O(N2) j : 0  N i:0N x x x x x x x x x x x x x x x x x x x x x
  31. 31. gayle in/gaylemcdgayleGayle Laakmann McDowell 31 Okay now thingsare getting tougher!
  32. 32. gayle in/gaylemcdgayleGayle Laakmann McDowell 32 Okay now thingsare getting tougher! Step 1: O(P)  P = numberof people Step 2: O(P * Y)  Y = max life span Step 3: O(L)  L = last death year O(P + P * Y + L)  O(P * Y + L)
  33. 33. gayle in/gaylemcdgayleGayle Laakmann McDowell 33 Validate Validate Runtime?  undefined
  34. 34. gayle in/gaylemcdgayleGayle Laakmann McDowell 34 Fibonacci Runtime? Eeek. Recursion?
  35. 35. gayle in/gaylemcdgayleGayle Laakmann McDowell 35 Fibonacci Eeek. Recursion? • Height of N • Each level doubles # nodes •  O(2N) time *** •  O(N) space Actuallyslightlylessforcomplexmathreasons.
  36. 36. gayle in/gaylemcdgayleGayle Laakmann McDowell 36 Fibonacci, part 2 Runtime? Eeek. Recursion? • Height of N • Each level has <=2nodes •  O(N) time •  O(N) space
  37. 37. gayle in/gaylemcdgayleGayle Laakmann McDowell 37 Reminders Drop constants Don’t drop non-constants Differentvariables Avoid ‘n’ Add vs. Multiply Recursion call tree
  38. 38. Solving Algorithms How to… attempt to solve a hard problem
  39. 39. gayle in/gaylemcdgayle 39 z Gayle Laakmann McDowell What is NOT expected To know the answers To solve immediately To code perfectly (It’snice.Itjustdoesn’t happen*.) *Okayfine.Ithappenedonce,in2000+hiringpackets.
  40. 40. gayle in/gaylemcdgayle 40 z Gayle Laakmann McDowell What IS expected Be excitedabout hard problems Drive!  Keep trying when stuck  More than just “correct” Pay attention to me! Write real code Showmehowyouthink!
  41. 41. gayle in/gaylemcdgayle 41 z Gayle Laakmann McDowell How To Approach CrackingTheCodingInterview.com“Resources”
  42. 42. gayle in/gaylemcdgayle 42Gayle Laakmann McDowell step Listen (for clues)
  43. 43. Gayle Laakmann McDowell 43gayle in/gaylemcdgayle What’s the clue? Anagram server  Ex: rates ->aster, stare, taser, tears Clue:why is it on a server? Key(sorted string) Value (list of words) aerst rates, aster, stare, taser, tears, dgo dog, god acll call … …
  44. 44. gayle in/gaylemcdgayle 44Gayle Laakmann McDowell step Draw an Example INTERSECTION SIZE: Find # elementsin common between two sorted, distinct arrays:
  45. 45. gayle in/gaylemcdgayleGayle Laakmann McDowell 45 Ex:Intersection ofTwo Sorted Arrays Most people draw somethinglike this: [1, 12, 15, 19] [2, 12, 13, 20]  Toosmall  Toospecial-case-y • same size, one commonelement, same index
  46. 46. gayle in/gaylemcdgayleGayle Laakmann McDowell 46 Ex:Intersection ofTwo Sorted Arrays Better: [1, 12, 15, 19, 20, 21] [2, 15, 17, 19, 21, 25, 27]  Big  No specialcases
  47. 47. gayle in/gaylemcdgayle 47Gayle Laakmann McDowell step Draw an Example Big Enough General Purpose +
  48. 48. gayle in/gaylemcdgayle 48Gayle Laakmann McDowell step Brute Force / Naive Stupid&terribleisokay!
  49. 49. gayle in/gaylemcdgayle 49Gayle Laakmann McDowell step Optimize Walk through brute force Look for optimizations
  50. 50. Gayle Laakmann McDowell 50gayle in/gaylemcdgayle Techniquesto Develop Algorithms BUD Space and Time Do It Yourself Recursion
  51. 51. Gayle Laakmann McDowell 51gayle in/gaylemcdgayle (A) Look for BUD Bottlenecks Unnecessary work Duplicated work
  52. 52. Gayle Laakmann McDowell 52gayle in/gaylemcdgayle What’s the bottleneck?  Ex: countingthe intersection [1, 12, 15, 19, 20, 21] [2, 15, 17, 19, 21, 25, 27]  Bottleneck:searching B
  53. 53. Gayle Laakmann McDowell 53gayle in/gaylemcdgayle What’s unnecessary?  Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000  Unnecessary: looking for d U
  54. 54. Gayle Laakmann McDowell 54gayle in/gaylemcdgayle What’s unnecessary?  Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000  Unnecessary: looking for d U
  55. 55. Gayle Laakmann McDowell 55gayle in/gaylemcdgayle What’s duplicated?  Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000  Duplicated: c, d pairs D
  56. 56. Gayle Laakmann McDowell 56gayle in/gaylemcdgayle What’s duplicated?  Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000  Duplicated: c, d pairs D c d c3 + d3 … … … 4 31 29855 4 32 32832 4 33 36001 … … … 5 59 205504 5 60 216125 5 61 227106 … … …
  57. 57. Gayle Laakmann McDowell 57gayle in/gaylemcdgayle What’s duplicated?  Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000  Duplicated: c, d pairs D c3 + d3 (c, d) … … 29855 (4, 31) 32832 (4, 32),(18, 30) 36001 (4, 33) … … 205504 (5, 59) 216125 (5, 60),(45, 50) 227106 (5, 61) … …
  58. 58. Gayle Laakmann McDowell 58gayle in/gaylemcdgayle What’s duplicated?  Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000 D
  59. 59. Gayle Laakmann McDowell 59gayle in/gaylemcdgayle What’s duplicated?  Ex: a3 + b3 = c3 + d3 (1 <=a,b, c, d<= 1000 D
  60. 60. Gayle Laakmann McDowell 60gayle in/gaylemcdgayle (B)Space/TimeTradeoffs Hashtables & other datastructures Precomputing
  61. 61. Gayle Laakmann McDowell 61gayle in/gaylemcdgayle (C)Do it yourself Findpermutationsof swithinb
  62. 62. gayle in/gaylemcdgayleGayle Laakmann McDowell 62 find abbcd in b a b c d b a e f d b b a c b d d f a e 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  63. 63. Gayle Laakmann McDowell 63gayle in/gaylemcdgayle (C)Do it yourself Findpermutationsof swithinb  s = abbcd  b = Findthem!  … now how didyou actuallydoit? b a b c d b a e f d b b a c b d d f a e
  64. 64. Gayle Laakmann McDowell 64gayle in/gaylemcdgayle (D)Recursion  Use, but don’t cling to, recursion “instinct”  Trybottom-up  “Backtracking”  Draw call-tree  Derive runtime  Find repeated subproblems  Subsets of a set  {} {}  {a}{},{a}  {a,b} {},{a},{b},{a,b}  {a,b, c} …  Subsets of {S1…Sn-1} +Sn to each
  65. 65. Gayle Laakmann McDowell 65gayle in/gaylemcdgayle Techniquesto Develop Algorithms BUD Space and Time Do It Yourself Recursion
  66. 66. gayle in/gaylemcdgayle 66Gayle Laakmann McDowell step Walk Through Know the variables andwhen they change
  67. 67. gayle in/gaylemcdgayle 67Gayle Laakmann McDowell step Write Beautiful Code
  68. 68. Gayle Laakmann McDowell 68gayle in/gaylemcdgayle How toWrite WhiteboardCode Write straight Top-leftcorner Use arrows if needed Error cases Good style Modularize (upfront!) Languagechoiceisuptoyou!
  69. 69. Gayle Laakmann McDowell 69gayle in/gaylemcdgayle Error Cases Good to check errors / boundaries! But consider the time…
  70. 70. gayle in/gaylemcdgayleGayle Laakmann McDowell 70 Good Style Spacing, line breaks, variable names
  71. 71. Gayle Laakmann McDowell 71gayle in/gaylemcdgayle Language Choice Java, Objective C, etc:Abbreviate Python, Ruby, JS,etc: Carefulwithbuilt-infunctions
  72. 72. gayle in/gaylemcdgayleGayle Laakmann McDowell 72 Modularization
  73. 73. Gayle Laakmann McDowell 73gayle in/gaylemcdgayle Modularize(Upfront!) I’ve learned nothing.
  74. 74. gayle in/gaylemcdgayle 74Gayle Laakmann McDowell step Testing FIRST Analyze  What’s it doing? Why?  Anything that looks weird?  Errorhot spots THEN use test cases  Small test cases  Edge cases  Biggertest cases BUT…  Test code, notalgorithm  Think as you test  Think before you fix Find permutationsof s withinb: s = abbc b = babcabbacaabcbabcacbb for (i = 0; i < b.len – s.len; i++) { if (isPerm(s, b.subs(i, s.len)) … }
  75. 75. gayle in/gaylemcdgayle 75 z Gayle Laakmann McDowell How To Approach CrackingTheCodingInterview.com“Resources”
  76. 76. Questions for Your Interviewer What do you want to know? 05
  77. 77. Gayle Laakmann McDowell 77gayle in/gaylemcdgayle Prepare some questions What’s made you happy / unhappy? What are your goals? Culture& work style Career paths Technology Interviewer’s experience
  78. 78. Final Thoughts And questions 06
  79. 79. gayle in/gaylemcdgayle 79 z Gayle Laakmann McDowell It’s done for a reason! Be agreat teammate. Be a great engineer.
  80. 80. Gayle Laakmann McDowell 80gayle in/gaylemcdgayle Butwait, there’s onemore thing... READY? Follow up with your recruiter to schedule your next steps. JOB POSTINGS: facebook.com/careers/teams/engineering SLIDES? Gayle.com -> Events -> search “Facebook”
  81. 81. gayle in/gaylemcdgayleGayle Laakmann McDowell 81 Other Resources Gayle.com CareerCup.com CrackingThe CodingInterview.com Or, follow me online • facebook.com/gayle • twitter.com/gayle • gayle.com • gayle@gayle.com • quora.com
  • ssuserf10f5d

    Apr. 22, 2021
  • SonglinYu

    Feb. 23, 2021
  • HumzaAhmad1

    Feb. 12, 2021
  • rangag

    Dec. 22, 2020
  • jacobdanner

    Jul. 24, 2020
  • QasimSoomro

    Jan. 29, 2019
  • ShengjiaLeviLian

    Nov. 22, 2018
  • FengChen39

    Oct. 31, 2018
  • Kiranramineni

    Oct. 19, 2018
  • PrafulGupta9

    Mar. 24, 2018
  • atothayu

    Mar. 18, 2018
  • GuptaSachin

    Mar. 2, 2018
  • ianormy

    Dec. 2, 2017
  • DipeshKhakhkhar1

    Sep. 29, 2017
  • sanmathigb

    Sep. 21, 2017
  • ssuserde8aee

    Sep. 6, 2017
  • michaelmaryahin

    Aug. 3, 2017
  • gurdeepsabarwal

    May. 17, 2017
  • PaulHaban

    May. 12, 2017
  • AmitMishra432

    May. 6, 2017

Vues

Nombre de vues

92 304

Sur Slideshare

0

À partir des intégrations

0

Nombre d'intégrations

426

Actions

Téléchargements

3 269

Partages

0

Commentaires

0

Mentions J'aime

96

×