Web Software Developer Interview Questions
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Web Software Developer interview questions shared by candidates
What is a JavaScript callback function?
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A callback function is a piece of JavaScript code that executes after the main function that the callback is attached to executes successfully. Less
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udaykanth, I would say that a .forEach() would be the most common and most basic use of a callback function. I'm just writing this to help anyone that might have a hard time thinking up a quick example if the come across this question themselves. Example: var numArray = [ 1, 2, 3 ] ; numArray.forEach( function( i ) { console.log( arr[ i - 1 ] ) } ) ; // logs out // 1 // 2 // 3 Less
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I don't think Bloomberg is a very good company. I am an excellent web developer and have gotten multiple offers from other companies with big names, but was rejected by Bloomberg. They are too demanding during the job interview and it becomes a game of how well you can interview as opposed to how talented an employee you are and how much you can contribute to the growth of the company. Less
How would you troubleshoot slow loading web pages and poorly performing stored procedures?
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Obviously, it is an easy answer though. First you want to check the network connection. If that seems to be working fine with other websites, check the code of the website. If the code is too cluttered then it will have problems loading. Make sure to organize the HTML so you can easily find clutter or useless text. Next, use a website validator - http://validator.w3.org/ . This website helps you find any errors on your page that may be causing a slow down. Hope this helps any, I use this for any problem I have. Less
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This is a very good question to ask anyone who is interested in web development. it gets them thinking and start working on problem solving. Less
Given a number n where n+1 and n-1 are prime, prove n is divisible by 6
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n+1 is prime, n+2 is prime... all prime numbers are odd, so n must be even (i.e., divisible by 2) in any set of 3 numbers (consider 1,2,3 or 4,5,6 or 20,21,22) at least one number is divisible by 3. since n+1 and n+2 can't be divisible by anything, n must be divisible by 3. therefore n is div by 6 Less
Say there was a function that took 1 second to execute and you needed to run this function 10 million times, how would you cut down on the execution time?
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Build a system that would run the functions concurrently.
They presented a demo page and asked me to streamline it to make it more interactive and presentable for a user (open to interpretation).
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Using JavaScript/jQuery, I created a simple slideToggle() click event on paragraph headers that collapsed them. I also changed the fonts and font weights to be more readable. Less
If we wanted to implement a method of tracking every click that the user made on the site, how would we want to do this?
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Place a JavaScript event listener for all clicks at the document level. Perform actions based on the details of the click. This problem had multiple branches and sub-questions, but the gist is that you would want to capture the events as they bubbled back up to the document level. There are other acceptable answers to this question. Less
1) Clustered and Non Clustered (SQL)?
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What other types questions were on the written test?
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Given a scnerio, create a database model
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How to improve performance?
1) Given a string of parantheses, check if the string is valid. ex: [[]] is valid, ][][ is not valid. How would you solve if the parantheses could be of different types like {,[,(
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Use a counter to track the status. Stack solution is no difference from this. Seeing an opening parenthesis increment the counter. Seeing a closing parenthesis decrement the counter. Check the counter is always non-negative. Counter has to be zero when string ends. Less
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Stack the parenthesis up. 1st of course the first parenthesis will go on to the stack. If you see a closing parenthesis, pop the stack and see if the parenthesis matches the one which is just read(closing one), if no match? error else keep going. Less
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To Aegis: If you take "[" as 1 and "]" as -1, then ][][ starts from -1. We can say that's invalid right away. Less
You have 1000 computers. Each computer contains a text file containing 1 billion floating point numbers. Design an algorithm or algorithms for extracting the top 1000 numbers from the entire list. Describe in detail how long it would take to process and why.
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1. 1000 computers - parallel 2. the problem can be divided into 2 parts. (1) find the top 1000 numbers from that 1 billion numbers in one computer To do this. we just need to use merge sort. Everytime use the left part. With some calculation, the solution for this is actually O(N). n is 1 billion. (2) get that top 1000 from the 1k * 1k list. (easy) Less
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There is a very nice parallel sorting algorithm with a very good iso-effeciency. It is called Sample-sorting. I would use that. Less
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You could do a bunch of crazy stuff too... Map reduce and parallel stuff is kinda a given. You'd be reading in strings, so before converting them to numbers, you could just check the position of the comma/point, and skip if your comma/point counter is at a higher value. If there's a minus sign in the beginning ignore the number, provided you already have 1000 positive numbers. Do something crazy with a stream and a router. Write a HD driver that scans the sign bit and exponent bits. lol Find a way to scan vertically for the comma/point. And you wouldn't be sorting you'd be searching. Ideally, it would take as long as it takes to read 1 text file from disk, because you'd be kinda faux streaming it through your code, plus a little extra time, multiplied by the number of files. You'd get a nice boost from dividing your file by the number of processors. 32 cores = 32 pieces of file being processed at the same time. Less