140 Google Interview Questions

October 24th, 2009 by lewis

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Here’s a list of 140 Google interview questions. Many of our clients have interviewed and received Google job offers. Contact us for a free 15 minute interview analysis before your Google interview.

SEE ALSO: Google PM interview classGoogle Software Engineer interview classGoogle Product Marketing interview class

Link to Google interview questions for:

Google Interview Questions: Product Marketing Manager

  • Why do you want to join Google?
  • What do you know about Google’s product and technology?
  • If you are Product Manager for Google’s Adwords, how do you plan to market this?
  • What would you say during an AdWords or AdSense product seminar?
  • Who are Google’s competitors, and how does Google compete with them?
  • Have you ever used Google’s products? Gmail?
  • What’s a creative way of marketing Google’s brand name and product?
  • If you are the product marketing manager for Google’s Gmail product, how do you plan to market it so as to achieve 100 million customers in 6 months?
  • How much money you think Google makes daily from Gmail ads?
  • Name a piece of technology you’ve read about recently. Now tell me your own creative execution for an ad for that product.
  • Say an advertiser makes $0.10 every time someone clicks on their ad. Only 20% of people who visit the site click on their ad. How many people need to visit the site for the advertiser to make $20?
  • Estimate the number of students who are college seniors, attend four-year schools, and graduate with a job in the United States every year.
Google Interview Questions: Product Manager
  • How would you boost the GMail subscription base?
  • What is the most efficient way to sort a million integers?
  • How would you re-position Google’s offerings to counteract competitive threats from Microsoft?
  • How many golf balls can fit in a school bus?
  • You are shrunk to the height of a nickel and your mass is proportionally reduced so as to maintain your original density. You are then thrown into an empty glass blender. The blades will start moving in 60 seconds. What do you do?
  • How much should you charge to wash all the windows in Seattle?
  • How would you find out if a machine’s stack grows up or down in memory?
  • Explain a database in three sentences to your eight-year-old nephew.
  • How many times a day does a clock’s hands overlap?
  • You have to get from point A to point B. You don’t know if you can get there. What would you do?
  • Imagine you have a closet full of shirts. It’s very hard to find a shirt. So what can you do to organize your shirts for easy retrieval?
  • Every man in a village of 100 married couples has cheated on his wife. Every wife in the village instantly knows when a man other than her husband has cheated, but does not know when her own husband has. The village has a law that does not allow for adultery. Any wife who can prove that her husband is unfaithful must kill him that very day. The women of the village would never disobey this law. One day, the queen of the village visits and announces that at least one husband has been unfaithful. What happens?
  • In a country in which people only want boys, every family continues to have children until they have a boy. If they have a girl, they have another child. If they have a boy, they stop. What is the proportion of boys to girls in the country?
  • If the probability of observing a car in 30 minutes on a highway is 0.95, what is the probability of observing a car in 10 minutes (assuming constant default probability)?
  • If you look at a clock and the time is 3:15, what is the angle between the hour and the minute hands? (The answer to this is not zero!)
  • Four people need to cross a rickety rope bridge to get back to their camp at night. Unfortunately, they only have one flashlight and it only has enough light left for seventeen minutes. The bridge is too dangerous to cross without a flashlight, and it’s only strong enough to support two people at any given time. Each of the campers walks at a different speed. One can cross the bridge in 1 minute, another in 2 minutes, the third in 5 minutes, and the slow poke takes 10 minutes to cross. How do the campers make it across in 17 minutes?
  • You are at a party with a friend and 10 people are present including you and the friend. your friend makes you a wager that for every person you find that has the same birthday as you, you get $1; for every person he finds that does not have the same birthday as you, he gets $2. would you accept the wager?
  • How many piano tuners are there in the entire world?
  • You have eight balls all of the same size. 7 of them weigh the same, and one of them weighs slightly more. How can you find the ball that is heavier by using a balance and only two weighings?
  • You have five pirates, ranked from 5 to 1 in descending order. The top pirate has the right to propose how 100 gold coins should be divided among them. But the others get to vote on his plan, and if fewer than half agree with him, he gets killed. How should he allocate the gold in order to maximize his share but live to enjoy it? (Hint: One pirate ends up with 98 percent of the gold.)
  • You are given 2 eggs. You have access to a 100-story building. Eggs can be very hard or very fragile means it may break if dropped from the first floor or may not even break if dropped from 100th floor. Both eggs are identical. You need to figure out the highest floor of a 100-story building an egg can be dropped without breaking. The question is how many drops you need to make. You are allowed to break 2 eggs in the process.
  • Describe a technical problem you had and how you solved it.
  • How would you design a simple search engine?
  • Design an evacuation plan for San Francisco.
  • There’s a latency problem in South Africa. Diagnose it.
  • What are three long term challenges facing Google?
  • Name three non-Google websites that you visit often and like. What do you like about the user interface and design? Choose one of the three sites and comment on what new feature or project you would work on. How would you design it?
  • If there is only one elevator in the building, how would you change the design? How about if there are only two elevators in the building?
  • How many vacuum’s are made per year in USA?
Google Interview Questions: Software Engineer
  • Why are manhole covers round?
  • What is the difference between a mutex and a semaphore? Which one would you use to protect access to an increment operation?
  • A man pushed his car to a hotel and lost his fortune. What happened?
  • Explain the significance of “dead beef”.
  • Write a C program which measures the the speed of a context switch on a UNIX/Linux system.
  • Given a function which produces a random integer in the range 1 to 5, write a function which produces a random integer in the range 1 to 7.
  • Describe the algorithm for a depth-first graph traversal.
  • Design a class library for writing card games.
  • You need to check that your friend, Bob, has your correct phone number, but you cannot ask him directly. You must write a the question on a card which and give it to Eve who will take the card to Bob and return the answer to you. What must you write on the card, besides the question, to ensure Bob can encode the message so that Eve cannot read your phone number?
  • How are cookies passed in the HTTP protocol?
  • Design the SQL database tables for a car rental database.
  • Write a regular expression which matches a email address.
  • Write a function f(a, b) which takes two character string arguments and returns a string containing only the characters found in both strings in the order of a. Write a version which is order N-squared and one which is order N.
  • You are given a the source to a application which is crashing when run. After running it 10 times in a debugger, you find it never crashes in the same place. The application is single threaded, and uses only the C standard library. What programming errors could be causing this crash? How would you test each one?
  • Explain how congestion control works in the TCP protocol.
  • In Java, what is the difference between final, finally, and finalize?
  • What is multithreaded programming? What is a deadlock?
  • Write a function (with helper functions if needed) called to Excel that takes an excel column value (A,B,C,D…AA,AB,AC,… AAA..) and returns a corresponding integer value (A=1,B=2,… AA=26..).
  • You have a stream of infinite queries (ie: real time Google search queries that people are entering). Describe how you would go about finding a good estimate of 1000 samples from this never ending set of data and then write code for it.
  • Tree search algorithms. Write BFS and DFS code, explain run time and space requirements. Modify the code to handle trees with weighted edges and loops with BFS and DFS, make the code print out path to goal state.
  • You are given a list of numbers. When you reach the end of the list you will come back to the beginning of the list (a circular list). Write the most efficient algorithm to find the minimum # in this list. Find any given # in the list. The numbers in the list are always increasing but you don’t know where the circular list begins, ie: 38, 40, 55, 89, 6, 13, 20, 23, 36.
  • Describe the data structure that is used to manage memory. (stack)
  • What’s the difference between local and global variables?
  • If you have 1 million integers, how would you sort them efficiently? (modify a specific sorting algorithm to solve this)
  • In Java, what is the difference between static, final, and const. (if you don’t know Java they will ask something similar for C or C++).
  • Talk about your class projects or work projects (pick something easy)… then describe how you could make them more efficient (in terms of algorithms).
  • Suppose you have an NxN matrix of positive and negative integers. Write some code that finds the sub-matrix with the maximum sum of its elements.
  • Write some code to reverse a string.
  • Implement division (without using the divide operator, obviously).
  • Write some code to find all permutations of the letters in a particular string.
  • What method would you use to look up a word in a dictionary?
  • Imagine you have a closet full of shirts. It’s very hard to find a shirt. So what can you do to organize your shirts for easy retrieval?
  • You have eight balls all of the same size. 7 of them weigh the same, and one of them weighs slightly more. How can you fine the ball that is heavier by using a balance and only two weighings?
  • What is the C-language command for opening a connection with a foreign host over the internet?
  • Design and describe a system/application that will most efficiently produce a report of the top 1 million Google search requests. These are the particulars: 1) You are given 12 servers to work with. They are all dual-processor machines with 4Gb of RAM, 4x400GB hard drives and networked together.(Basically, nothing more than high-end PC’s) 2) The log data has already been cleaned for you. It consists of 100 Billion log lines, broken down into 12 320 GB files of 40-byte search terms per line. 3) You can use only custom written applications or available free open-source software.
  • There is an array A[N] of N numbers. You have to compose an array Output[N] such that Output[i] will be equal to multiplication of all the elements of A[N] except A[i]. For example Output[0] will be multiplication of A[1] to A[N-1] and Output[1] will be multiplication of A[0] and from A[2] to A[N-1]. Solve it without division operator and in O(n).
  • There is a linked list of numbers of length N. N is very large and you don’t know N. You have to write a function that will return k random numbers from the list. Numbers should be completely random. Hint: 1. Use random function rand() (returns a number between 0 and 1) and irand() (return either 0 or 1) 2. It should be done in O(n).
  • Find or determine non existence of a number in a sorted list of N numbers where the numbers range over M, M>> N and N large enough to span multiple disks. Algorithm to beat O(log n) bonus points for constant time algorithm.
  • You are given a game of Tic Tac Toe. You have to write a function in which you pass the whole game and name of a player. The function will return whether the player has won the game or not. First you to decide which data structure you will use for the game. You need to tell the algorithm first and then need to write the code. Note: Some position may be blank in the game। So your data structure should consider this condition also.
  • You are given an array [a1 To an] and we have to construct another array [b1 To bn] where bi = a1*a2*…*an/ai. you are allowed to use only constant space and the time complexity is O(n). No divisions are allowed.
  • How do you put a Binary Search Tree in an array in a efficient manner. Hint :: If the node is stored at the ith position and its children are at 2i and 2i+1(I mean level order wise)Its not the most efficient way.
  • How do you find out the fifth maximum element in an Binary Search Tree in efficient manner. Note: You should not use use any extra space. i.e sorting Binary Search Tree and storing the results in an array and listing out the fifth element.
  • Given a Data Structure having first n integers and next n chars. A = i1 i2 i3 … iN c1 c2 c3 … cN.Write an in-place algorithm to rearrange the elements of the array ass A = i1 c1 i2 c2 … in cn
  • Given two sequences of items, find the items whose absolute number increases or decreases the most when comparing one sequence with the other by reading the sequence only once.
  • Given That One of the strings is very very long , and the other one could be of various sizes. Windowing will result in O(N+M) solution but could it be better? May be NlogM or even better?
  • How many lines can be drawn in a 2D plane such that they are equidistant from 3 non-collinear points?
  • Let’s say you have to construct Google maps from scratch and guide a person standing on Gateway of India (Mumbai) to India Gate(Delhi). How do you do the same?
  • Given that you have one string of length N and M small strings of length L. How do you efficiently find the occurrence of each small string in the larger one?
  • Given a binary tree, programmatically you need to prove it is a binary search tree.
  • You are given a small sorted list of numbers, and a very very long sorted list of numbers – so long that it had to be put on a disk in different blocks. How would you find those short list numbers in the bigger one?
  • Suppose you have given N companies, and we want to eventually merge them into one big company. How many ways are theres to merge?
  • Given a file of 4 billion 32-bit integers, how to find one that appears at least twice?
  • Write a program for displaying the ten most frequent words in a file such that your program should be efficient in all complexity measures.
  • Design a stack. We want to push, pop, and also, retrieve the minimum element in constant time.
  • Given a set of coin denominators, find the minimum number of coins to give a certain amount of change.
  • Given an array, i) find the longest continuous increasing subsequence. ii) find the longest increasing subsequence.
  • Suppose we have N companies, and we want to eventually merge them into one big company. How many ways are there to merge?
  • Write a function to find the middle node of a single link list.
  • Given two binary trees, write a compare function to check if they are equal or not. Being equal means that they have the same value and same structure.
  • Implement put/get methods of a fixed size cache with LRU replacement algorithm.
  • You are given with three sorted arrays ( in ascending order), you are required to find a triplet ( one element from each array) such that distance is minimum.
  • Distance is defined like this : If a[i], b[j] and c[k] are three elements then distance=max(abs(a[i]-b[j]),abs(a[i]-c[k]),abs(b[j]-c[k]))” Please give a solution in O(n) time complexity
  • How does C++ deal with constructors and deconstructors of a class and its child class?
  • Write a function that flips the bits inside a byte (either in C++ or Java). Write an algorithm that take a list of n words, and an integer m, and retrieves the mth most frequent word in that list.
  • What’s 2 to the power of 64?
  • Given that you have one string of length N and M small strings of length L. How do you efficiently find the occurrence of each small string in the larger one?
  • How do you find out the fifth maximum element in an Binary Search Tree in efficient manner.
  • Suppose we have N companies, and we want to eventually merge them into one big company. How many ways are there to merge?
  • There is linked list of millions of node and you do not know the length of it. Write a function which will return a random number from the list.
  • You need to check that your friend, Bob, has your correct phone number, but you cannot ask him directly. You must write a the question on a card which and give it to Eve who will take the card to Bob and return the answer to you. What must you write on the card, besides the question, to ensure Bob can encode the message so that Eve cannot read your phone number?
  • How long it would take to sort 1 trillion numbers? Come up with a good estimate.
  • Order the functions in order of their asymptotic performance: 1) 2^n 2) n^100 3) n! 4) n^n
  • There are some data represented by(x,y,z). Now we want to find the Kth least data. We say (x1, y1, z1) > (x2, y2, z2) when value(x1, y1, z1) > value(x2, y2, z2) where value(x,y,z) = (2^x)*(3^y)*(5^z). Now we can not get it by calculating value(x,y,z) or through other indirect calculations as lg(value(x,y,z)). How to solve it?
  • How many degrees are there in the angle between the hour and minute hands of a clock when the time is a quarter past three?
  • Given an array whose elements are sorted, return the index of a the first occurrence of a specific integer. Do this in sub-linear time. I.e. do not just go through each element searching for that element.
  • Given two linked lists, return the intersection of the two lists: i.e. return a list containing only the elements that occur in both of the input lists.
  • What’s the difference between a hashtable and a hashmap?
  • If a person dials a sequence of numbers on the telephone, what possible words/strings can be formed from the letters associated with those numbers?
  • How would you reverse the image on an n by n matrix where each pixel is represented by a bit?
  • Create a fast cached storage mechanism that, given a limitation on the amount of cache memory, will ensure that only the least recently used items are discarded when the cache memory is reached when inserting a new item. It supports 2 functions: String get(T t) and void put(String k, T t).
  • Create a cost model that allows Google to make purchasing decisions on to compare the cost of purchasing more RAM memory for their servers vs. buying more disk space.
  • Design an algorithm to play a game of Frogger and then code the solution. The object of the game is to direct a frog to avoid cars while crossing a busy road. You may represent a road lane via an array. Generalize the solution for an N-lane road.
  • What sort would you use if you had a large data set on disk and a small amount of ram to work with?
  • What sort would you use if you required tight max time bounds and wanted highly regular performance.
  • How would you store 1 million phone numbers?
  • Design a 2D dungeon crawling game. It must allow for various items in the maze – walls, objects, and computer-controlled characters. (The focus was on the class structures, and how to optimize the experience for the user as s/he travels through the dungeon.)
  • What is the size of the C structure below on a 32-bit system? On a 64-bit?

struct foo {

char a;
char* b;
};

 

Google Interview: Software Engineer in Test
  • Efficiently implement 3 stacks in a single array.
  • Given an array of integers which is circularly sorted, how do you find a given integer.
  • Write a program to find depth of binary search tree without using recursion.
  • Find the maximum rectangle (in terms of area) under a histogram in linear time.
  • Most phones now have full keyboards. Before there there three letters mapped to a number button. Describe how you would go about implementing spelling and word suggestions as people type.
  • Describe recursive mergesort and its runtime. Write an iterative version in C++/Java/Python.
  • How would you determine if someone has won a game of tic-tac-toe on a board of any size?
  • Given an array of numbers, replace each number with the product of all the numbers in the array except the number itself *without* using division.
  • Create a cache with fast look up that only stores the N most recently accessed items.
  • How to design a search engine? If each document contains a set of keywords, and is associated with a numeric attribute, how to build indices?
  • Given two files that has list of words (one per line), write a program to show the intersection.
  • What kind of data structure would you use to index annagrams of words? e.g. if there exists the word “top” in the database, the query for “pot” should list that.
Google Interview: Quantitative Compensation Analyst
  • What is the yearly standard deviation of a stock given the monthly standard deviation?
  • How many resumes does Google receive each year for software engineering?
  • Anywhere in the world, where would you open up a new Google office and how would you figure out compensation for all the employees at this new office?
  • What is the probability of breaking a stick into 3 pieces and forming a triangle?
Google Interview: Engineering Manager
  • You’re the captain of a pirate ship, and your crew gets to vote on how the gold is divided up. If fewer than half of the pirates agree with you, you die. How do you recommend apportioning the gold in such a way that you get a good share of the booty, but still survive?
Google Interview: AdWords Associate
  • How would you work with an advertiser who was not seeing the benefits of the AdWords relationship due to poor conversions?
  • How would you deal with an angry or frustrated advertisers on the phone?
Sources
http://news.ycombinator.com/item?id=266663
http://tihomir.org/crazy-questions-at-google-job-interview/
http://www.drizzle.com/~jpaint/google.html
http://www.gamedev.net/community/forums/topic.asp?topic_id=299692
http://careers.cse.sc.edu/googleinterview
http://job-interview.blogspot.com/2005/02/google-interview-product-marketing.html
http://www.theregister.co.uk/2007/01/05/google_interview_tales/
http://money.cnn.com/2007/08/29/technology/brain_teasers.biz2/index.htm
http://blogs.lessthandot.com/index.php/ITProfessionals/EthicsIT/google-interview-questions
http://placementsindia.blogspot.com/2007/09/google-top-interview-puzzles.html
http://linkmingle.com/user/interview_questions/google_interview_questions
http://discuss.joelonsoftware.com/default.asp?interview.11.626758.33
http://mindcipher.com/puzzle/78-clock-works
http://www.glassdoor.com
http://bluepixel.ca/blog/?p=69
http://www.businessinsider.com/my-nightmare-interviews-with-google-2009-11

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99 Responses to “140 Google Interview Questions”

  1. November 04, 2009 at 7:43 pm, Financial Samurai said:

    Great questions! But, the time to join Google was 5 years ago, not today.

    You think you'll get rich with an option strike price above $500/share? Sorry. NEXT.

    Reply

    • August 05, 2011 at 9:36 am, tdi78 said:

      sounds like *someone* didn’t get hired. ;)

      Reply

    • August 26, 2011 at 12:36 am, arshad said:

      Does anyone tell me if anyone gives an interview for the position of technical program Manager ..???

      Regards.

      Reply

    • September 25, 2012 at 4:25 pm, The Future said:

      Fast forward to now…at 750 per share. You could have gotten rich.

      Reply

  2. November 04, 2009 at 10:06 pm, Zen Capitalist said:

    Even if the strike prices are above $500 a share, they have some of the happiest employees. Not to mention, some of the best paying jobs in the valley. Not too shabby.

    Reply

    • April 11, 2012 at 7:33 pm, foo bar said:

      exact opposite of reality: people are overworked, overstressed, and underpaid.

      Reply

      • July 06, 2012 at 10:36 am, DrKeek said:

        Name a tech job where this is not true

        Reply

        • January 20, 2013 at 5:16 pm, No one said:

          Engineers at Valve seem pretty happy.

          Reply

  3. November 05, 2009 at 1:30 am, Tony Ruscoe said:

    Your links at the top of this post are linking to your edit URLs. You need to update those to point to the published URL.

    Reply

  4. November 05, 2009 at 2:38 am, Lewis, AKA Seattle Interview Coach said:

    Thanks Tony. Fixed.

    Reply

  5. November 05, 2009 at 10:27 am, Tony Symons said:

    Hi Lewis. Just read the article re. the Google questions in today's Guardian. Any chance of you giving answers to the 10 questions featured?
    Thanks. Tony Symons

    Reply

  6. November 05, 2009 at 2:25 pm, Anonymous said:

    To Financial Samurai-

    I'm sure someone said that about Berkshire some years ago too.

    Reply

  7. November 06, 2009 at 7:14 am, Sha said:

    "How would you deal with an angry or frustrated advertisers on the phone?"

    That one's easy: you don't. I remember reading that it's impossible to speak to a real person at Google's AdWords department.

    Reply

  8. November 06, 2009 at 7:48 am, Anonymous said:

    These interview questions are largely urban myth. I never heard 90% of these asked, and brain teasers have been banned for like 5 years at the company.

    Reply

    • October 11, 2012 at 2:04 pm, Joe said:

      I definitely got some questions like these when I screened for an engineering position very recently. (Very recently: Still don’t know if I got the job) I didn’t get silly brain teasers, but I did get questions about sort algorithm runtimes, and had to write some example code for them. It was not excessively hard, but unlike most of my interviews where I tell them what I know, they actually make you demonstrate it. For an hour. This is the one time where you can answer the question “Where where I ever use this bit of knowledge when I couldn’t look it up online?” Answer: In a Google interview.

      Reply

  9. November 06, 2009 at 8:20 am, Mike said:

    interesting article. some questions are 'impossible' to answer ;)

    i posted your article on http://www.OptimistList.com for other readers to enjoy and learn from.

    Reply

  10. November 07, 2009 at 10:10 pm, schulz said:

    Another question – How do you check a list of Google interview questions to ensure there are no duplicates?

    Reply

  11. November 11, 2009 at 4:24 am, Anonymous said:

    Interesting .. btw i am curious to know the anwers also.. where could we find ?

    Reply

  12. November 13, 2009 at 11:47 pm, Anonymous said:

    I dunno – maybe try http://www.google.com?

    Reply

  13. November 16, 2009 at 10:55 am, Oliver Mezquita said:

    $500 per share? Check out Warren Buffet's Berkshire Hathaway …
    My God, i don't think they expect candidates to answer all of those questions…

    Reply

  14. November 19, 2009 at 7:16 am, hari babu said:

    good information, usefull for people attending for interviews.

    Reply

  15. November 19, 2009 at 10:44 am, BillR said:

    They don't have some of the happiest employees. Average software engineer is only there for a few years before they move on. In fact, if you've been there for a while and NOT been headhunted, it sort of looks weird. In any case, it's long hours, and working on weekends is not at all uncommon (I once worked 11 weeks straight without a day off, and many of those were 14-16 hour days). They give you breakfast, lunch and dinner for a reason, you know.

    They also aren't the best paid. Google is famous for underpaying their employees. They make up for it with their very generous benefits package. But in terms of straight salary, they're about 20% below other valley tech companies.

    By the way, I interviewed a few hundred people for SWE positions while I was at Google. Many of your example questions not only aren't asked, they're explicitly forbidden. You are not allowed to ask frivolous brainteaser crap about manhole covers (there are actually two shapes which won't fall back into the hole, in case you were curious) or why 0xDEADBEEF is 3735928559 in decimal. You don't ask that nonsense because the questions are crap and tell you absolutely nothing about the candidate.

    You're supposed to ask open-ended questions that test problem solving and general knowledge, then get into specifics. Once answered, you pick a topic in the answer and you dive in deeper. The goal to to find out where the candidates run out of ideas. Typically you want to test general knowledge, and find an area that you two can really dig deep into. At that point, you send the candidate to the whiteboard and have them start writing code.

    So you don't bother with asking questions with simple factoid answers. For example, you aren't going to ask what a mutex is, you're going to talk about them when the candidate's code on the whiteboard has a race condition or whatever.

    Similarly, you don't ask "How would you store a million phone numbers?", you ask "How would you sort a million phone numbers on a machine that only had 256KB of memory?" You want to see if they can figure out how to solve the problem creatively given your constraints. And when they write it out, you ask "OK, so that solution is O(n log n)… how can you make it more efficient?" And if they don't know about Big O notation, well then you immediately know you're not hiring that person.

    My favorite question was to ask them to write a little program that solved a rubik's cube. It's got a bunch of possible answers and some that I saw were actually quite creative. (The best way, again in case you're curious, is to "open the cube up" and treat it as an asymmetrical grid. You go through it row and column and match up the six colors.)

    Some real advice: When given open-ended questions, immediately ask questions in return that would help define the constraints. They want you to sort something, ask if it's a list of INTs, that sort of thing. But the best advice I can give anyone interviewing there is to sharpen your ability to understand engineers for whom English is a second language. Chances are very good that you'll be interviewing with someone who is difficult to understand. Sad, but true.

    Reply

    • May 22, 2012 at 10:45 pm, Abhinav said:

      Thanks for the tips!!!!!!!!

      Reply

  16. December 01, 2009 at 4:26 pm, Gayle said:

    Great list! CareerCup.com has another 3000+ interview questions for Software Engineers (from Microsoft, Amazon, Google, etc).

    Reply

  17. December 03, 2009 at 4:47 am, RIchard Goldberg said:

    By embedding real situations on the "quiz interview", they may be harvesting for potential solutions/optimizations, for free, among top brainers. Brilliant.

    Reply

    • November 07, 2012 at 10:14 am, Mr. Fair said:

      It should be absolutely illegal to ask questions such as “how do you think our products can be improved?” . The interviewers are getting great ideas from candidates who might never be employed, but probably have their ideas stolen.
      Where are the great lawyers to fight for people ‘s right or abuse?

      Reply

  18. December 03, 2009 at 6:45 pm, Schratboy said:

    I'm surprised there wasn't the question: Would you, without question, accept micro-chip implantation in your body as a condition to joining Google?

    Reply

    • November 24, 2011 at 9:40 pm, notimpressed said:

      Yeah, agreed, they probably want you to agree to the microchip implantation out in the parking lot, as a condition for parking your car and getting into the building. Step one: sell your soul permanently for a chance to even possibly get to kiss one g-ass.

      The problem with something that is this much of a ‘gotcha’ is twofold.

      1. Superman syndrome – if they DO get someone who answers all of the stupidity in the right way, it just means they are ok or well-prepped for specific questions like this. It doesn’t necessarily even mean they are a good coder or whatever else there is to do at google, like
      a) code
      b) write code
      c) code some more on your birthday
      d) code all night and weekend

      2. This shows me that google is still really a playboy type company in which the founders/leaders have a culture that they permeate, which promotes and condones intimidation of employees. As a potential employee, you are naturally intimidated by some or all of these questions. Even if you are not, it also shows they have a ‘protected club’ type mentality, which will STILL stink up the place once you are inside their prison wall of well fed prisoners.

      If anyone at ANY company EVER EVER EVER EVER asks me something like ‘why is a manhole cover round’ or the ‘golf ball school bus’ question, I will say ‘GIVE ME MY GODDAMN RESUME BACK’. Make them HAND you the hardcopy and WALK OUT. Your personal integrity is worth FAR MORE than your salary, or getting to ‘sleep’ (for 5 minutes) in the office while you ‘recharge’ your new-age batteries for 4 more hours after a 12 hour day. Oh. And they can KEEP their swag and shit, too. And I don’t give a FUCK about the food either. ‘Nuff said.

      Reply

      • June 22, 2013 at 5:22 am, James said:

        Wow. If I were interviewing you, I’d ask, “What’s wrong with Google?” I’d then find your answer highly entertaining, call security, hand you your precious hard copy c.v. and tell you to get off the premises. You have a poor attitude and THAT’S what makes a terrible employee.

        Reply

  19. December 11, 2009 at 11:43 pm, Alex said:

    Great collection ! Though I as know working in Google is not as good as it sounds. Yes, food is free but code is messy…

    Reply

  20. January 13, 2010 at 9:35 pm, Ed Smiley said:

    two of the problems turn out to be the same problem, stated somewhat differently ;)

    Reply

  21. January 17, 2010 at 10:55 am, Susan said:

    If you are looking for a place, a site where you can learn how to act on a perfect job interview, i suggest you to go to interview guide . Nice looking and everything included. I mean everything important related to a job interview.
    Prepare yourself for the job of your dreams! It's coming…

    Reply

  22. February 04, 2010 at 11:46 am, Anonymous said:

    As someone who went through a Google Interview last week, I can absolutely confirm that all of my Software Engineer interviewers asked *this type* of question. Not exactly any of these, but very close.

    Reply

  23. February 16, 2010 at 11:38 pm, mangaroo said:

    Gee, the software engineer in test questions seem much harder than the software engineer questions. Seems engineer + test = even more important? Or there were less candidates available from which to compile a more comprehensive list of interview questions in the area of software engineer in test?

    Reply

    • June 21, 2013 at 8:24 am, raj said:

      I think it’s so because testing sometimes requires higher level skills (especially system-level testing) than coding. The developer writes his or her piece of software and tests if it works as a separate unit; however, when you combine many hardware and software elements into one big system and have to test it, finding causes of problems can be really difficult…

      Reply

  24. February 18, 2010 at 9:58 pm, Ryan said:

    Good Grief they ask some darn-old tough questions.

    Tough Interview Questions

    Reply

  25. February 27, 2010 at 8:00 am, Slybacon said:

    I have written a blog page about the "country where families want exactly one boy" question": http://ping.fm/lH8yi . The are many pages on the web which suggest an answer to this question but most of them miss the point in my opinion.

    Reply

  26. March 18, 2010 at 6:08 pm, camilo lopes said:

    good! post! and an excellent questions!

    Reply

  27. April 04, 2010 at 7:25 pm, Anonymous said:

    Great resource for all job seekers. Thank you the questions

    Regards,
    Admin,
    http://www.interviewqueries.com

    Reply

  28. May 11, 2010 at 11:02 am, Scott said:

    Column AA is the 27th column in a spreadsheet, not 26th as stated in the question above (assuming Excel uses the full English alphabet–I personally don't care to run Excel). Thanks for posting these fun questions.

    Reply

  29. June 24, 2010 at 12:07 am, CommonInterview said:

    Thanks awesome set of questions, I am adding solutions to some of the questions here:

    http://commoninterview.com/Programming_Interview_Questions/

    Reply

  30. June 25, 2010 at 11:48 am, Ian R McAllister said:

    Wow, some of these are blind dumb obvious, and some are great insights into how the company selects the right and best. But I guess that all are essential for the Google job applicant. I am looking for specific questions re Product Management for a client of mine, do you have anything on that? Thanks!

    Reply

  31. July 20, 2010 at 7:33 am, Sparks said:

    I’ve gone through the interview process twice now with Google (once in 2007 and once in 2010), and since the more information out there for those undergoing pre-Google-Interview stress, the better, I wrote it up:
    http://www.stochasticgeometry.ie/2010/07/20/interviews-google/

    Reply

  32. September 22, 2010 at 2:41 pm, Ryan said:

    I remember buying 1000 Google shares in 2005 @ $200 each, i sure made a nice return on investment, Don't get me wrong, Google is not my god but they still make 20 billion dollars a year…

    Reply

  33. November 11, 2010 at 5:21 pm, Dan said:

    If you're an unhappy google employee – we're hiring. http://www.tallchair.com :) We are making a new social mobile media technology. If you want to build something in a smaller company that you get to help shape – then send us an email.

    Reply

  34. November 14, 2010 at 12:15 pm, foxorrabbit said:

    Regarding the Google-Berkshire comparison: when Berkshire was $500 per share, the value of all the shares was less than $1 billion, less than 0.1% of the value of all companies at that time. Over 30 or so years, Berkshire's share price increased by 200x and the company is now valued around $200 billion.

    Google, at $600 per share, with 320 million shares outstanding, is already worth about $200 billion. This valuation represents somewhere in the area of 1% of the aggregate value of all public companies in the United States. So for Google to increase by even 10x — without a 10x increase in the stock market overall — its value would need to increase to near 10% of the value of all U.S. companies combined. The law of large numbers makes that almost impossible.

    Reply

  35. November 30, 2010 at 5:42 am, stephan said:

    Great questions wish we could see the answers would make for interesting reading.

    Reply

  36. December 28, 2010 at 5:43 am, Anonymous said:

    Most of these questions aren't "great", they are a stupid waste of time. Asking a software engineer how many piano tuners can fit in a bus or some such crap tells you nothing except whether or not that person can bs their way through the response.

    Reply

  37. January 26, 2011 at 7:19 am, Teras Info said:

    quite confusing … he .. he ..

    Reply

  38. February 20, 2011 at 5:33 pm, Tom W said:

    I went on an interview for a software engineer position at Google and these are just the type of questions they asked. Granted, in total, they only asked like 3 or 4 total but they are just the type of questions they ask.

    Reply

  39. February 23, 2011 at 9:43 pm, job interviews tips said:

    This is the best question list i have ever saw. You have done a fabulous job in your blog. Keep up the good work.

    Reply

  40. February 24, 2011 at 8:29 am, Lewis, AKA Seattle Interview Coach said:

    Margaret, thanks for the kind words. I'm glad you enjoyed the article!

    Reply

  41. February 28, 2011 at 6:38 am, Natasha Lauren said:

    Great post! I was really impressed with the questions.

    Reply

  42. March 22, 2011 at 7:24 pm, tania said:

    This is a nice article..
    Its very easy to understand ..
    And this article is using to learn something about it..

    c#, dot.net, php tutorial

    Thanks a lot..!

    Reply

  43. March 24, 2011 at 5:20 am, Trabajar en Facebook, Google o Twitter said:

    [...] ejemplo, Google tiene fama de ser la más dura en este aspecto (si no te lo crees, lee estas 140 preguntas que suelen realizar a los entrevistados) pero también hay buenas noticias: en este momento tienen [...]

    Reply

  44. March 31, 2011 at 8:29 am, Sean said:

    I recently went for a Google interview at their Singapore office. Their were a panel of 4 interviewers all interviews were back to back. I am still waiting to hear as they said after this the results go to a panel I must say I am not sure if I really want to join them as I was not really impressed because:

    1. Average tenure of someone in thier staff in existing role is 6 mo. All good for googling but what do you accomplish in this timespan and move on so soon to new projects.

    2. I was a bit disgusted because the second interviewer started asking me personal questions as to where I am from. I am a Canadian of Indian origin and I guess he was looking for some Indian accent, then the one that took the cake is when he asked whether I am married to a Chinese. Also wheer do my parents live. he keept bragging he is from Manhattan and trying to get used to Singapore.

    3. I could see they are a smart bunch and will be fun to work with. They are a happy lot with some cool perks but I fealt they were becoming very inward looking. This got confirmed recently with the amazon marketplace just announced. Also lot of revenue is still very much tied to search.

    I am still waiting but a bit confused if this is the place.

    Reply

    • April 29, 2011 at 7:13 pm, R said:

      Sean, what position did you interview for?

      Reply

  45. April 25, 2011 at 11:56 pm, 2 eggs problem « 程序人生 said:

    [...] http://www.impactinterview.com/2009/10/140-google-interview-questions/ Categories: dp LikeBe the first to like this post. 评论 (0) 引用通告 (0) 发表评论 引用 [...]

    Reply

  46. June 22, 2011 at 11:51 pm, Vasathi said:

    Great Question.
    I refer joining Google as one of the best achievement in my life.

    This article would be great if answers were also published.

    Anyways Thanks !!

    Reply

    • July 03, 2011 at 11:32 pm, LB said:

      @Vasathi: it’d help others a lot if you briefly share your experience. Also share how did you prepare yourself to get into Google. Thanks.

      Reply

  47. June 23, 2011 at 2:16 am, 140 Google Interview Questions | Impact Interview | Munaf Sheikh said:

    [...] you like these questions, click the link below for more. via 140 Google Interview Questions | Impact Interview. This entry was posted in Bookmark and tagged Google, Interview, Questions. Bookmark the [...]

    Reply

  48. July 20, 2011 at 9:50 pm, 140 Google Interview Questions | Impact Interview | nhanphung said:

    [...] 140 Google Interview Questions | Impact Interview. [...]

    Reply

  49. August 15, 2011 at 10:46 pm, Interview Experience With Google said:

    [...] 140 Google Interview Questions [...]

    Reply

  50. September 27, 2011 at 6:42 am, Perguntas feitas em entrevista de emprego da Google « Olhar De Toupeira said:

    [...] elabora entrevistas de emprego para a Google e para a Microsoft, divulgou à já algum tempo no seu blog 140 perguntas que foram aplicadas a pessoas que foram entrevistadas para várias vagas de emprego [...]

    Reply

  51. September 27, 2011 at 8:09 pm, Job Interviews Only Have Three Questions | Dice Blog Network said:

    [...] about different interview questions and how to answer them. Others have lists of questions asked at specific companies. Crowd sourcing, almost: Everyone going through an interview at a specific company adds to the list [...]

    Reply

  52. October 14, 2011 at 4:06 am, Mihai Roman said:

    1. You have a stream of infinite queries (ie: real time Google search queries that people are entering). Describe how you would go about finding a good estimate of 1000 samples from this never ending set of data and then write code for it.

    and

    There is a linked list of numbers of length N. N is very large and you don’t know N. You have to write a function that will return k random numbers from the list. Numbers should be completely random. Hint: 1. Use random function rand() (returns a number between 0 and 1) and irand() (return either 0 or 1) 2. It should be done in O(n).

    Solution: reservoir sampling: http://dailyjobquestions.com/2011/10/08/reservoir-sampling/

    2. Write a function (with helper functions if needed) called to Excel that takes an excel column value (A,B,C,D…AA,AB,AC,… AAA..) and returns a corresponding integer value (A=1,B=2,… AA=26..).

    Solution: http://dailyjobquestions.com/2011/10/12/excel-columns/

    3. You are given a list of numbers. When you reach the end of the list you will come back to the beginning of the list (a circular list). Write the most efficient algorithm to find the minimum number in this list. Find any given number in the list. The numbers in the list are always increasing but you don’t know where the circular list begins, i.e.: 38, 40, 55, 89, 6, 13, 20, 23, 36.

    Solution: O(log(n)) considering that you can randomly access the elements of the list:
    http://dailyjobquestions.com/2011/10/13/circular-binary-search/

    4. Maximum sub-sequence, maximum sub-matrix, LCS, LIS:
    Solutions: http://dailyjobquestions.com/tags.html#dynamic%20programming

    5. There is an array A[N] of N numbers. You have to compose an array Output[N] such that Output[i] will be equal to multiplication of all the elements of A[N] except A[i]. For example Output[ 0 ] will be multiplication of A[ 1 ] to A[N-1] and Output[ 1 ] will be multiplication of A[ 0 ] and from A[ 2 ] to A[N – 1]. Solve it without division operator and in O(n).

    Solution: http://dailyjobquestions.com/2011/10/11/vector-multiplication/

    Reply

  53. October 17, 2011 at 4:57 pm, John said:

    Hmmm…..interview questions that don’t really mean anything in their answers – is a bit like fishing in a pond where there are no fish – doesn’t make much sense – try using a good job description and doing good job analysis in your co and not fly by the night wackiness such as this. Ahh – no wonder some jobs remain open for a year or 2 with no veritable success. The hiring manager may as well do the job themselves.

    Reply

  54. November 04, 2011 at 6:02 pm, Zoltan said:

    1. There are dogs. Each dog have two parents and some number of children, they have their own cubs, etc. Design a function which checks if two dogs are related in some way (marriage is not counted). Effectievly this means finding a common ancestor in a tree which is not arranged in any way.

    2. There are two _sorted_ arrays A and B. Write a function which produces two other arrays X=A-B and Z=B-A where A-B means elements which exist in A but not in B and B-A is vice versa. Complexity is linear to A and B lengths.

    Reply

  55. November 22, 2011 at 6:05 am, Steve said:

    What a load of crap. If Google continues down this path to select new employees they will end up hurting themselves in the long term. Right now the bet and brightest are fighting to get into the company so they will tolerate this type of treatment. They would be hardpresed to hire a “wrong” person because they a fishing from a well stocked, highly qualified pool. Like shooting fish in a barrell.
    However, bad news travels fast – they are insulting some very qualified people who are going to tell their friends and colleagues about their experience. Pretty soon no one will want to work with a bunch of lunatics and they will have a less rich pool to draw from. They will then have to learn how to actually interview and properly qualify a candidate to select a good one.
    Where is the bloody management team there – have they never heard of behavioural based interviewing techniques – do they understand the importance of balance of IQ and EQ.
    I guess if you are hiring a bunch of straight coders who can be kept in a room and you throw food in once in a while their methods are ok. For any role in the organization desinged to increase business and move the company forward this type of interviewing is a recipe for disaster.

    Reply

    • January 05, 2012 at 3:35 am, xx said:

      this is not an issue. look at the large management consulting companies like McKinsey, Berger, BCG etc. bright people for a large part but assholes 100%. they are there for the money and the name on the CV, so it does not matter to them what the environment is like. and they love those types of questions. try this: how many tennis balls are there in france?

      Reply

      • May 14, 2012 at 11:16 pm, Rohan said:

        My answer to the question:
        Total number of tennis balls in France: 1375890
        If the interviewer disagree, tell him to go and count himself ;-)

        Reply

  56. February 08, 2012 at 11:54 am, Revelan las 10 preguntas más insólitas para trabajar en Google | Noticias de tecnologia, programacion y mas said:

    [...] información del cracked.com, impactinterview.com, página donde un asesor laboral comparte las preguntas que les hicieron a sus clientes (alrededor [...]

    Reply

  57. February 26, 2012 at 8:37 am, Adeel Ahmed said:

    I have an experience of 5 years.Worked in 3 companies.I haven’t ever been asked such type of questions.I think these sort of questions for the people of other planet lolz

    Reply

  58. February 26, 2012 at 3:59 pm, Ceritaku Diterima Bekerja di Google | LavaGyre said:

    [...] kamu tidak perlu menjadi seorang jenius untuk bisa melaluinya. Coba cek daftar pertanyaan menurut ImpactInterview untuk mendapat gambaran lebih jauh. Seorang teman saya yang bekerja di HRD pernah memberitahu saya [...]

    Reply

  59. April 24, 2012 at 7:33 am, Preguntas poco comunes para una entrevista de trabajo | LaNuevaEconomía said:

    [...] 140 preguntas para trabajar en google [...]

    Reply

  60. April 26, 2012 at 10:20 am, Axis Talento Ejecutivo said:

    [...] 140 preguntas para trabajar en Google [...]

    Reply

  61. April 29, 2012 at 5:26 am, SANTOSH said:

    cant we get the Google maps interview questions……..?

    Reply

  62. May 02, 2012 at 2:47 pm, Rizwan Sayani said:

    These questions are really awesome. I feel that they really help sharpen the programmer’s mind. I plan on doing about 5 or more a day.
    I would love to work for google one day. I mean it’s google. I believe that if they really put their minds to it and enhanced and properly marketed some of their deprecated ideas, they could really be a lot bigger and better than apple. Google prides itself on their search engine and google collaboration however they could do much more. Hope a googler sees this and says “hey, we want you!” Google can one day rule the world!!!! muahhahahahha!!!!!

    Reply

  63. June 06, 2012 at 8:36 pm, Guest said:

    I have a invite for a phone interview for business system integration analyst position, any advice on the interview questions asked for this role?

    Reply

  64. June 21, 2012 at 3:21 pm, Google Interview Questions - Interlocked Pieces said:

    [...] came across an old blog post on an interview-prep website which appears to have gone out of business in February of 2012. I was [...]

    Reply

  65. August 31, 2012 at 2:58 am, java67 said:

    Great questions, Thanks

    Reply

  66. September 08, 2012 at 3:33 pm, justice served said:

    hiring managers are idiots. here’s a new one: ask questions that are relevant to the job. If you are asking a software developer how to write a program to solve a rubik’s cube, and you are not in the rubik’s cube solving business, you should be fired for wasting company time.

    Reply

    • January 24, 2013 at 9:03 am, Atta said:

      Interviews are for checking if you’re hiring the right person, not for the interviewee to do some free work for your company. If you want a software engineer and he is not capable of approaching the Rubik’s Cube problem, he’s not a good engineer. The purpose of the question is see how you approach problem solving; you could fail trying to solve the cube but pass the interview anyway.

      Reply

  67. September 27, 2012 at 4:29 am, Modern Interviews said:

    [...] And for those of you interested here is the link to the Lewis Lin Google Interview Questions http://… [...]

    Reply

  68. November 15, 2012 at 9:38 am, prasad said:

    hey i am, seeking for the IT job can anyone help me out..??

    Reply

  69. January 10, 2013 at 9:26 pm, Eric Roth said:

    Thank you for sharing these provocative, and often challenging questions.

    Reply

  70. March 09, 2013 at 4:53 pm, Aven said:

    Good reco of interview questions.
    It would be great to add all answers :)

    Thanks

    Reply

  71. March 23, 2013 at 10:37 am, Doug said:

    Apart from CLR and Skiena’s algorithms book, I would recommend the following books focussed on real coding interviews questions which contains great details(real questions with real answers as expected by the google/amazon interviewer):

    *Top 10 coding interview problems asked in Google with solutions: Algorithmic Approach By Dr Lin Quan

    *Elements of Programming Interviews: 300 Questions and Solutions By Adnan et al.

    *Programming Pearls By Dr Bentley
    *More Programming Pearls By Dr Bentley

    These books helped me greatly in my Amazon’s onsite interview recently.

    Practicing topcoders questions can be an additional help if it suits individual interest.

    Reply

  72. April 06, 2013 at 12:25 pm, David said:

    I have been on zero job interviews since I graduated college 12 years ago – I have worked at that same company all this time. So I have no earthly idea what other companies do, but when I interview engineers, I want really don’t care about seeing them answer some “gotcha” mind games nor even seeing that they can implement some obscure algorithm from memory.

    Chances are, if you have written a b-tree or any such rudimentary algorithm in your professional life, you’re doing something wrong. For the overwhelming majority of software engineers, you’re using a language that has these structures built in. You need to be able to use the object model or library or whatever it is that you have in your environment, but getting someone to regurgitate how to build tree structure XYZ from college is not a meaningful exercise. In the off chance that you need to write a b-tree in your professional life because for whatever reason the one built in to your language doesn’t meet your needs, you aren’t going to be doing it from scratch – you can have a textbook or Wikipedia article or whatever sitting right next to you. You still don’t need to do it from scratch.

    I also hate making someone write something up on a white board while I watch unless it’s something very brief and it’s easier for them to write it rather than say it. It’s a waste of my valuable time to sit there while you write a program on a whiteboard – I’d rather either (a) give you a computer to do it or (b) just sit you in a conference room with a written test and say come get me when you’re done and ready to talk.

    Reply

  73. April 21, 2013 at 8:43 am, 140 otázok od Google, ktoré môžete dostať pri pohovore | AndroidNEWS.sk said:

    [...] Zdroj: impactinterview.com [...]

    Reply

  74. June 20, 2013 at 7:23 am, Aplusclick said:

    There is a free collection of the tech-job interview logic puzzles with the answers at

    http://www.slideshare.net/igorkokcharov/10-answers-on-techinterview-riddles

    and more than 150 logic riddles in the book:

    https://itunes.apple.com/book/job-interview-logic-puzzles/id578135550?mt=11

    Reply

  75. June 24, 2013 at 5:50 pm, DD said:

    What do they ask the property maintenance engineers? How much wood could a woodchuck chuck?

    Reply

  76. June 28, 2013 at 1:31 pm, Noogle said:

    Ah yes, and the world will never be “normal” again, for the worse unfortunately.

    How about hiring someone who will apply themselves, be dependable, and hard working? That’s a novel idea. Right?

    And then you have these pompous arrogant smarty pant types who think they know it all. They may know it all literally, but they don’t have an ounce of common sense or social skills to get them through what has built human societies for hundreds of thousands of years.

    Google can go pound sand. In 10-15 years, it will be that era’s equivalent of GM, Ford, GE, etc. What a joke. Karma always comes knocking on your door. Are you ready to answer the door?

    Oh, and I was offered a job at Google, and turned it down when they showed this ugly side, and their sub-culture.

    Reply

  77. July 22, 2013 at 12:29 pm, anon said:

    Can anyone give some advise for HR coordinator’s job at google

    Reply

  78. July 25, 2013 at 9:11 am, KP said:

    One I came across on a Google phone interview:

    Design and code the algorithm for Google’s Page Rank algorithm, published in the late 90′s using Markov chains.

    Reply

  79. August 01, 2013 at 5:31 pm, Lily said:

    Unfortunately, I will never pass a Google interview based on my programming skill alone… but may be my looks will help! :-)

    Reply

  80. June 05, 2014 at 11:20 am, sandhya said:

    hi frnds, I have attended for the company google for the position of analyst which was conducted in global logic ..1st round is jam ..i got selected ..next round is face to face intrvw..they gave some tpics like google products ,google maps, logical reasoning , direction sense and etc..so plz any one suggest me the links where i can read these all in detail..plz plz help me

    Reply

  81. July 15, 2014 at 4:08 pm, Olumide said:

    Alternative route, start up your own tech company, google buys it and you’re in. In and rich.

    Reply

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