The Daily WTF: Curious Perversions in Information Technology

Tsaukpaetra · 2015-10-04 Reply Admin

Perhaps I'm just missing something, but where does i come from? Wait, scratch that, where does data come from? I'm thinking some obfuscation has occurred!

Filed under: there is no cow level

DogsB · 2015-10-06 Reply Admin

There is a belief that if you keep looking once you've found what you're looking for you might find gold.

RobyMcAndrew · 2015-10-06 Reply Admin

Tsaukpaetra:
where does i come from?

Sounds like you be coming from the west country me old beauty.

Quite · 2015-10-06 Reply Admin

No, that would be "Where be I coming from, me lover?"

flabdablet · 2015-10-06 Reply Admin

DogsB:
There is a belief that if you keep looking once you've found what you're looking for you might find gold.

https://www.youtube.com/watch?v=9auOCbH5Ns4

RFoxmich · 2015-10-06 Reply Admin

Our submitter writes: "I challenged a few of my colleagues to come up with a worse implementation, that would still seem reasonable. No one was able to do so." I imagine some of you in the comments will take that as a challenge.

Well I could make this O(n^m) for arbitrary m pretty easily just by re-writing either DestnameToDest, or more insidiously DbGetNext, but I'm feeling lazy today.

OttoX · 2015-10-06 Reply Admin

Solve one problem, create another: Code snippets are not equal. Original code finds LAST match, new code finds FIRST match !

dkf · 2015-10-06 Reply Admin

RFoxmich:
or more insidiously DbGetNext

That reminds me of a bug I need to find time to fix…

cheong · 2015-10-06 Reply Admin

I assume adding some sorting statement to the data fetching function will fix that.

blakeyrat · 2015-10-06 Reply Admin

https://www.youtube.com/watch?v=EiO9_PJ0h8Q

EatenByAGrue · 2015-10-06 Reply Admin

It's the "still seems reasonable" clause that makes it impossible to implement the following algorithm for searching a list (in pseudocode):

found = null
while not found:
    list.shuffle()
    if list[0] == search_term:
        found = list[0]
        break

That will work with an average speed of o(n^2*log n) assuming a fair shuffle function, unless of course search_term isn't in the list in which case the program will not halt.

flabdablet · 2015-10-06 Reply Admin

EatenByAGrue:
the following algorithm for searching a list

That's eerily similar to little ms. flabdablet's method for tracking down lost toys and items of clothing.

cellocgw · 2015-10-06 Reply Admin

Reminds me of someone's response (in a blog, not an actual interview) to "write code to extract a square root without using any math library," which went, more or less. {find square root of x} while TRUE y = random() if abs(y^2-x) < eps; break continue

Tsaukpaetra · 2015-10-06 Reply Admin

How does one actually find the square root? We were never told this in any math class I've attended...

Filed under: Oh, well just use this table of 4-significant-digit results if you don't have a calculator

accalia · 2015-10-06 Reply Admin

Tsaukpaetra:
How does one actually find the square root?

there are multiple ways, but one common one is:

Estimate - first, get as close as you can by finding two perfect square roots your number is between.
Divide - divide your number by one of those square roots.
Average - take the average of the result of step 2 and the root.
Use the result of step 3 to repeat steps 2 and 3 until you have a number that is accurate enough for you.

sauce

dkf · 2015-10-06 Reply Admin

Tsaukpaetra:
How does one actually find the square root?

The standard algorithm is an application of Newton-Raphson, which converges fast and is actually pretty easy to code to high standard.

https://en.wikipedia.org/wiki/Newton%27s_method#Square_root_of_a_number

Tsaukpaetra · 2015-10-06 Reply Admin

dkf:
T

accalia:
t

TMYK :rainbow:

The Most Pessimistic Search

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