# Staff engineer Interview Questions

# 3K

Staff Engineer interview questions shared by candidates### How many race heats are needed to find the 3 fastest pinewood derby cars out of a field of 8, if only 4 cars can run at a time (assuming that every car will always run the way/speed and each lane is exactly equivalent)?

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so is the answer 4 heat 1 (first 4 car) + 1 (4 second set) + 1( Top 2 from first + Top 2 from second set) + 1 (3 car heat among the 3rd placed car) Less

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Only two races of four cars in each. Get the times of all cars and sort them. You don't need any more races because the times will be the same in subsequent races. :) Less

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4 if we cant measure time

### Just leave a message here with the questions & I will post the solution in 5-10 minutes if I have got the same questions or I will write the solution if I know it. I got 3 coding problems to be done 90 minutes.

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Thanks for quick help, it helped me to clear the coding round. But is the use of CCAT now & how can I work on this? Less

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For CCAT one can prepare for mathematical aptitude questions, questions around the next number in the given series of numbers. Have some practise around simple simple probability, permutation/combination questions. You will also see many questions around the given figures where you need to identify the next figure or which figure doesn't match in the given list of figures. If you are Indian candidate then you will have 20 minutes to solve these 40 questions, else you will get 15 minutes to solve 50 questions. First part will be your Personality test with no time limit & you will get about 150 questions to select the right option as per your view. Second part is aptitude test & calculate the per question time for you & try to answer within that time only or else select your best possible wild guess. There is no negative marking. Now you have given the answers as per your understanding, later you will get the result as per their understanding. All The Best. Less

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I had 2 rounds - Round1 : General Java, ElasticSearch & RestService questions. Round2 : How will you have the counter of visitors, in your Rest based backend. Write some code. What & why will you chose ArrayList or LinkedList for the given scenario. Puzzle on coins flip in dark & divide them in 2 groups. Less

### If you have a 600 digit number with only 0's and 1's, and exactly 300 1's, can the number be a square?

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The answer should be YES: @gustion: your example with 49 (7 pwr2) is correct but with 25 (5 pwr2) is incorrect. 7 in binary is 111 (3 1-bits is half of 6 bits), but 5 in binary is 101 (2 1-bits does not equal half of 6 bits). In general, any binary number with n-bits, half of which are 0's and half are 1's is a square of a binary number with half the number of bits, all being 1-value bits. In addition, the number's magnitude will be n/2-1 1-bits followed by n/2 0-bits followed by the last 1-bit. For example, lets say we have a 16-bit number. The number which will have 8 1-bit and 8 0-bit binary digits and also be a square is: 1111 1110 0000 0001 (7 1-bits followed by 8 0-bits followed by 1-bit) and this number is a square of 1111 1111 Binary number with 600 bits and 300 1-bits will have a magnitude of 299 1-bits followed by 300 0-bits followed by 1-bit, and it will be a square of a 300-bit number with the magnitude of 300 1-bits. Less

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Well on a simple note, 9's binary is 1001, a 4 digit binary with two 1's and two 0's, and is a perfect square. The same analogy should also be true for any such number. Less

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No

### C Basics and Networking Concepts

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To the best of my understanding

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What were the questions, can you please share, will be helpful.

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Cool,, you cleared it. What is their expectation? Question pls..

### It was positive experience. People were nice. Like craft demo which help to have discussion with team instead of traditional interview structure.

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I felt did great !

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Powerful post

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I tried rooftop slushie mentioned above and it was pretty helpful. I recommend it. Less

### Given a series of strings, find the biggest common prefix.

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What? Prefix is not started from the very first string? Jesus I cannot read Eng!

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x = ["Ravite", "Raviteja", "Ravby", "Raviejaain","Ravi" ] #Given String y = x[0] for i in x: if len(i)> len(y): y = i fin = [] y = list(y) for i in range(len(y)): count = 0 for j in range(len(x)): if y[i]==x[j][i]: count +=1 if count == len(x): fin.append(y[i]) else: break if len(fin) > 0: print "".join(fin) else: print "No common prefix in series" Less

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/** * Jun Zheng, Rice Univ * Given a series of strings, find the biggest common prefix. * Real question of VMware * Java7; running time: O(n^2) * @param str * @return */ private String biggestPrefix(String[] strs){ String prefix=strs[0]; for(int i=1;i0;i++){ int j; for(j=0;j0)? prefix:"No such prefix!"; } Less

### How do you trace your code without gdb?

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printf? He said wrong.

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strace

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Logging at each callback from start to end in a separate file.

### Write code to draw a circle.

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Use recursion to split the draw circle into half in each call until the size reaches threshold to draw an arc. Duplicate the arc post recursion. Less

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public class DrawCircle extends Frame { public void paint(Graphics g) { Graphics2D ga = (Graphics2D) g; ga.setPaint(Color.red); ga.drawOval(300,300,200,200); } public static void main (String args[]) { DrawCircle frame = new DrawCircle(); frame.addWindowListener( new WindowAdapter() { public void windowClosing(WindowEvent we) { System.exit(0); } } ); frame.setSize(800, 800); frame.setVisible(true); } } Less

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There's quite an extended back and forth in actual interviews for questions like this, so nothing quite like real practice. The Prepfully VMware Staff Engineer experts have actually worked in this role, so they're able to do an honest-to-God accurate mock, which really puts you through the paces. prepfully.com/practice-interviews Less

### During lunch, I was given a problem on how I would optimizing the traffic at the access point used at the cafeteria, we discussed about it during the entire time allotted for lunch

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Think out loud, it was more of a general discussion than a question-answer session. The interviewer was very helpful too. Less

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Hi, DId they inform about you being rejected? When did you interview happened? It will be of great help if you can answer these!! :) Less

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Hello sir, can you tell me how many days it took for a onsite interview after your phone process, I already had a interview with software team and waiting for results. Less

### Programming question of reverse number using recursion, some medium level Java, selenium questions, collections

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If you are confident in terms of your experience, you can crack the interview

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how many days it will take to declare HR round results?

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How many days it will take to declare technical discussion round?