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Admin
I don't tolerate riddles in interviews simply because it happens too often where the interviewer expects the interviewee to struggle with it until the little "gotcha!" is revealed. Useless! I understand the point of the riddles is different, but my experience (and seemingly the experience of many others) shows they are not generally used in a manner that might allow to glean a bit of information about the interviewee.
Admin
"Laden or bin Laden?"
Do I get the job?
/Jihad Nazi
Admin
LED bulbs do not generate heat - what kind of light bulbs are we talking about? riddle for the riddler.
Admin
"I'd ask Boeing"
Your network connection is down, so you can't even give me an estimate? No hire.
"Who would build such a stupid, broken box?"
Your predecessor, and it has 10 million deployments. Fixing them all would be prohibitively expensive. We're looking to hire somebody who can solve problems for us cheaply. Not you? No hire.
"Obviously, we'd leave the slow guy behind."
I guess in this case, it's you, since you can't solve any of our simple problems. No hire.
Admin
Whenever I sit down for an interview and the interviewer starts off with a brain teaser question, I politely interrupt them and say, "I understand why you are asking this sort of question, but I feel it is very important that I get an accurate impression of the type of work you will expect from me as well. Could you please take a few moments to explain the (project, problems, technical issues, etc.) first and then continue where we left off?".
If this throws the interviewer off, it's a HUGE red flag to me in that it implies the company is not really thinking about finding the right person for a job, or the job itself is not well defined.
Admin
Nobody has mentioned hats yet -- as I recall, that was how most of the 900 original comments got started. (Red, blue, three, can't see own hat, how do you choose?)
I remember being in the middle of this nightmare on the OP. Curiously, or perhaps cretinously, it inspired me to buy the book "How do you move Mount Fuji?" which deals with precisely these questions and a lot of interesting Stanford-Binet history besides.
This had unfortunate effects.
Dim Bulb Interviews 2.0 hit me the very next time I interviewed after reading the book, at a Prestigious Financial Institution in the hell-hole of the universe (read London). They had both kinds of questions there: country and western.
The "western" (Richmond) type was an incessant barrage of Fujiesque stupidity. I breezed through all of them with ease, right up to the one with two lengths of fuse that aren't even, but burn through in an hour. How to time 45 minutes? This is where I made the classic interview error.
"I've read the Fuji book and I can answer all the questions, even the pirate one (which I think relies on an unsound application of induction) and the one with the goblin in the middle of the lake. I've got a mental block on this one. Do you have the book handy?"
Bad move. Bad move.
But not as bad as my answer to the "country" question, asked by a spotty twenty-two year old *nix freak fresh out of college.
El Spotto: "What would you use 'cut' for?" Me: "Nothing."
Not quite sure which one lost me a job I would have loathed, really. Don't care, either. Have been watching their stock price decline ever since, with the sole intention of glorying in Schadenfreude.
Admin
Bright LEDs emit heat -- that's why you need heat dissipators near them...
OK, it's not as bad as with the usual "we heat up some wolfram(?) fiber to get heat and therefore light with just 3% of the powerinput converted to light, but even with 10 or even 30% efficiency there's still quite an amount of heating the air involved. Just assume you want to get the same "amount" of light as with a 3% incandescent (3W of "light" in a 100W incandescent) you'd need a 10W LED (or equivalent of smaller LEDs) at 30% efficiency to replace it (ideal conditions, etc) so it will still get quite warm if left "burning" for a longer time. Hey, even my USB DVB-T receiver is gets notably warm if watching TV for some time - and USB is no more than 2.5 Watts (5V, 500mA).
Of course if you talk about a childs toy with three 20mW red LEDs...
Admin
How would you determine the weight of a Boeing 747?
Check the tires and see what weight they are rated for.
or
measure the wingspan and use it to calculate the weight.
Admin
According to my 30 seconds of googling, the first method is too unreliable, and from reading this thread , all planes have a logbook of weights and are regularly plopped on scales, so the obvious answer is correct. The fun part is that the common curveballs (what if you don't have a scale?) are easily met with "The plane doesn't fly due to safety concerns".
Admin
Well, okay, it wasn't Mt. Fuji, specifically; it was a mountain in Hermitage, Tennessee, in another life (circa 1974). A bassist friend and I had moved there to sell ourselves as a duo -- bass and drums -- and as luck would have it, they were building a new highway within walking distance of the apartments we rented (it takes a while to get established in the music biz in Nashville). So we hired on as heavy equipment operators, a field in which we both had some experience. We worked a deal with the foreman that as long as they had work for us, we could work on the highway between gigs, and then take off on the road when we got work with a band.
My friend Jack drove a Cat #9 dozer, and I drove a pull (or scraper, or earth-mover; I think the names for those things are regional). And we literally moved a mountain into a valley. Jack and another dozer were positioned at the top of this mountain, and me and about five other pulls drove up one side and were pushed down the other side until our cradles were full, and then we bounced and careened our way down the slope and into the valley, where we dumped out our loads and went back up for more.
It paid, if I recall correctly, $3.82 per hour, which was a livable wage for the place and time. We worked there off and on for about five months, until I found out my wife was pregnant with our first child, and I decided to take up a more dependable line of work.
I drove back through there again a couple of years back. Tried to find those same apartments, but they were gone. I did see, though, that they succeeded in getting the rest of that mountain moved, even without my help. How 'bout that.
Admin
This really sounds like The Guerilla Guide to Interviewing and in contrary to the WTF article I think it actually makes sense. At least if the interview consists of more than only riddles.
Admin
For the 747. Apply x amount of force to move it forward over y amount of time. Doing this we will find the velocity. And with the velocity, finding the mass is simple algebra.
force(x) * time(y) = mass * velocity
mass = force * time / velocity
Admin
If you're hiring in a situation where you know that occasionally you and your employees will have to work outside their comfort zone, why wouldn't you want to try to separate the people who would respond with something like "hey, this is new and interesting, I've never thought about this sort of stuff before" (and even be motivated by the novelty) from the people who would get annoyed about how "this isn't in my job description!" or the like?
Sure, you can claim that the people in the former group are then not, technically, out of their comfort zone when confronted with with the novelty, but frankly that's fairly irrelevant. But if you insist, look at it this way: you're trying to find people whose comfort zone includes a high tolerance for novelty and an interest in a wide range of things. And that's a good thing, if said traits are applicable to the job being interviewed for. To dismiss the usefullness of such questions/problems out of hand is just as silly as to use them in an interview for a mundane, routine job where they would be irrelevant.
Of course, it does seem fairly common to see people taking the "if some of it is good, a lot of it is better" approach and instead of asking diverse/unorthodox---yet still practical and appropriate---questions, going to ridiculous extremes with inane trick questions where there's only one "right" trick or questions that rely on familiarity with a few particular pieces of obscure knowledge even though that knowledge has no relevance to the job at hand. (I suspect that another reason a lot of people like those is so that they can feel superior about knowing the trick while the interviewee flounders in confusion, and those people are jack***es through and through.) But unexpected stuff happens a lot in life, and someone who would walk right away if they didn't initially see how a question could be relevant to the job is someone I'd want a lot less than someone who'd have enough interest in the unusual to stick around to see just how it was connected.
Admin
if you are ever stumped, just answer that the shape prevents it from falling down the manhole because no matter which way you place it in the hole, the cross section is always the same. 9 times out of ten this will answer any job interview question.
Admin
Return it for a full refund - you don't expect your employees to use broken or substandard equipment, do you?
Recommend replacing the closed source box with an open-source box. Read the documentation.
You let 10 million boxes out the door, and you don't know how they're wired up? I think I'll pass on the job (due to the inevitable safety issues impending).And of course, there's the final answer of "Well, theoretically, I'm God, so I just make the box work the way I want it to. If you'd like a practical demonstration, I'd need a physical box."
Admin
Time and distance are easy to measure, but how would you measure force?
Admin
My answer to #1 would be (especially if it were a MS interview): "Look it up on Google." :-)
Admin
How do you know the precise drag on the tires and bearings? Also, why aren't you using the airport scale? Do you write bytecode by hand too?
/esse
Admin
I might just verbify whatever their current search offering is called just to make them cringe.
Admin
"Did you give up immediately without even trying? If so, I don't want you working for me. "
Do I give up immediately when presented with an utterly ludicrous and contrived problem that I can't even begin to imagine why you're asking about, let alone expecting an answer to? Quite possibly - I'm looking for a job, and don't have time to fuck around.
"The worst thing you could do is argue with me about the validity of the test. Again, I wouldn't want you working for me. "
You don't like to employ people who disagree with you? Suggesting that you believe you could never, ever be wrong?
Admin
"Your network connection is down, so you can't even give me an estimate? No hire. "
Why are you asking me the weight of a 747 when the network connection is down? The network connection is down! Fix it! Have you checked whether it's plugged into the router? And is the router switched on? Sometimes there's dust between the socket and the wall, if you remove the socket and give the plug a good wipe that might help.
I can't even begin to imagine the morons you must have at your workplace, courtesy of your bizarre hiring practices. Probably the kind of people who can figure out the names and sexual predilections of fifteen lightbulbs in an opaque box, but would be utterly flummoxed if they were asked to screw one in.
Admin
I hav interview next week. I try Boeing problem to solve. I know sizeof(747) but not weight. Plz send your codes.
Admin
Complete agree on the programming test. Where I work, everybody goes through a 2-3 hour programming under somewhat realistic conditions (i.e. you're left alone, have access to the web, etc). These tests are relatively simple and not brain teasers (we don't expect anybody to write a solver for Soduko in 2 hours).
While I initially scoffed at that idea, after a few years of being on the interviewing side I find the input from these programming tests extremely valuable.
You have no idea how many folks with "years of industry experience" sit in that conference room for two hours, remove a few lines here and there from the skeleton that we provide them and did not add a single line of code.
Brainteasers on the other hand, I find fairly useless, since they usually do not represent any realistic conditions that you tend to encounter as a soft-developer.
Admin
Admin
Duh! Apparently my problem solving skills are much better than my arithmetic skills. Which explains why I became a programmer.
Admin
If a switch is permanently set, is it still a switch?
Admin
As long as you specify that it's meant to be piped into another program. Implicit buttumptions just make an butt out of people.
Then again, that's clbuttic gold-plating so you can tell he's a real programmer :P
I like the one about the farmer with the chicken, fox and pig who has to cross a stream but his canoe can only take 1 animal at a time. Additionally the fox, if left unattended, will eat the other animals.
Admin
All irrelivant, given the questiobn was "how would you determine the wieght...?" not "how much does a boeing 747 weigh?"
Admin
I've worked with too many incompetents and fuckheads. If the interview process filters out the assholes, all the better.
I'd rather be asked a few too many dumb questions rather than too few questions that don't remove the tards from the workforce.
Admin
10min guy and 1 min guy cross with 10 imn guy holding torch. 1 min guy reaches other side, 2 min guy starts crossing, he reaches other side, 5 min guy crosses, 10 min guy reaches the other side 2 mins after him, with the light.
Admin
I'd just tell the interviewer that I can no longer see the box as it's been consumed by an SEP field and is invisible.
I't either that or my Peril Sensitive Sunglasses have activated because there's a radioactive cat in the box.
These sorts of things happen all the time.
Admin
Woops - 2 min guy fell off the bridge because 10 min guy was in front and 2 min guy couldn't see the gaps :)
Admin
Obviously call a lot of my friends to change it (I'm Polish) ;)
The dock method seems kinda drastic. What about a hill, a couple of tools and basic mechanics? I mean it's a plane and stuff, prolly worth a couple of bucks.
Admin
Admin
Admin
Maybe I missed something.... I thought the question was: how would you determine...?
not: waht is.....?
Admin
Chris sayz:
Actually, that's the most common solution. You don't have to design a special bicycle, just use a standard tandem. I know of several people that do this, and I've seen some doing it.
I've also heard of a few blind people who ride standard bicycles. As I understand it, they ride with a sighted friend who shouts instructions to them. I've never seen it myself. And I wouldn't recommend doing it on the busy streets where I ride! ;->
Admin
Better still: Q: How many Christmas trees were sold last year? A: 2x Q: What's x ? A: Half the number of Christmas trees sold last year
Admin
Naw... Manhole covers are round because the hole needs to be round. The hole needs to be round because the worker who climbs into the hole is pretty much round. You seen these guys? Lots of them are kina' round... ;->
Admin
Such silly puzzles basically serve to weed out the people who do not perform well under that specific type of look-over-your-shoulder-breath-down-your-neck-solve-it-now-while-I-watch-you sorts of "pressure". In 20+yrs of software development, I've never once had to do real work in any such environment. Software development "pressure" is more about schedule/quality stress, not about solving puzzles while we watch you with a microscope. There's a whole class of people, and I count myself as one, who are perfectly good developers and architects, but who work best in a let-me-think-it-through-in-peace sort of environment. I once interviewed at Microsoft as a contractor, told the manager, in advance, that I didn't do well with interview puzzles, and invited him to give me a programming problem to solve in a day. I took it back to work, solved and programmed the solution over my lunch hour, emailed it back, and got hired. My years at M$ were very productive and enjoyable, and all made possible by an understanding interviewer/manager who recognized that good developers come in many flavors, and are not to be weeded-out through artificial, idiotic, interview-induced puzzle-solving pressures.
Admin
How would you determine the weight of a Boeing 747?
Google it.
Admin
Answers:
Google. (I'm sure that would go over really well in a Microsoft interview.)
Not possible. Too many variables if I only get 1 crack at it.
If I leave everyone behind, I can get across the fastest.
Admin
My first thought, oddly enough, was the water-displacement method. Methinks that would be awfully hard on the aircraft however, especially if the engines were running. Hmm, should we consider the keep-it-dry constraint? How about the advantages/disadvantages of saltwater vs fresh? How will barnacle accumulation during weighing be accounted for? Would this be a stripped-bare plane, or one fully-outfitted for a Saudi Arabian prince?
No, no, no, this isn't about practical solutions, this is just "so we can see how you think". We don't want someone who can coolly mull over all the facets of a problem, determine the possible approaches and their respective strengths and weaknesses, and come up with an appropriate and practical solution. We just want you to "solve" the damn puzzle RIGHT NOW in any ad-hoc way that you choose as long as it seems clever and don't ask any damn questions, just do it.
No wonder M$ software has earned such a poor reputation among users.
Admin
At that point you say "Kobayashi Maru" and walk out.
Admin
Can't agree more.
Admin
I've been asked to write code on whiteboards in interviews -- it has some merit, but no one really does this anyway, you think about the problem, get some ideas, look at some docs, write some code, run, test, debug, repeat...
The last several interviews I've given, I've given the candidate my laptop and some mocked-up data and asked them to write some simple programs in the language of their choice. This has done a good job of weeding out the ppl who can write code from the ppl who can talk about it. And you get to see if they can solve problems, think of corner cases before they encounter them, and handle the small things that most of us do day-to-day...
Admin
Interview while still an undergrad went as follows: Note that at this stage I had absolutely no experience.
Q: There's a production bug in the code that's affecting X and costing us money every second. What do you do? A: Talk to Dev Lead. Reproduce and try to fix it. Check logs, check the code, check the db, etc. Show solution to Dev Lead.
Q: They don't do anything, what do you do? A: Talk to their manager.
Q: They don't do anything, what do you do? A: Try to find someone to listen.
Eventually saying that I wouldn't bother trying anymore, which didn't seem to go over well, but I don't see how there's another answer. I mean if their tact was that nobody gave a crap, then why would I? Who am I to presume that I know better than they did.
I even asked what sort of answer they were looking for, and they didn't know how to answer that. They gave the 'it's your approach that matters' ... so I guess communication with the team I'm in, trying to fix the problem, and escalating to superiors was the wrong approach. Silly me.
Admin
Yes, I agree completely. Whiteboarding is only useful for kicking around possible approaches/solutions to problems.
As an interviewer, you yourself are not thinking of the corner cases. The corner cases in the form of developers who don't think/code well while under the hot interrogation lamp of an interview. They may be superb developers, but are corner-cases that you're going to miss out on simply due to your interview techniques.
Most of us do our day-to-day work in relative privacy in an environment that we create for ourselves that is conducive to thinking and problem solving. For some, that may be listening to AC/DC at full blast while working the problem. For others it might be kicking back at Starbucks for a couple of hours, espresso in hand, working it out. High-pressure, artificial puzzle-solving/coding interviews only serve to weed out people who may be ultimately some of your best problem-solvers.
Admin
Riddles are a great way to eliminate the large number of people who can't even adhere to three or four basic requirements. Go read the comments for the original version of this article and you'll see what I mean.
Admin
I could just get a fish-scale type scale and grease the wheels and measure the force required to displace the mass... F=ma, do the math^H^H^H^Hphysics.