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I was asked to crack a program in a job interview

erenyagdiran.github.io

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Re: I was asked to crack a program in a job interview

#21

Post by dragonwriter »

Swizec wrote: post #8
freehunter wrote: post #5

Really nice overview of the process. I was hoping to get into debugging and breaking code, but my career took a wild turn away from that part of the job. It's still something I would like to learn, so I'm reading as much about it as I can. I'm going to take this way off topic here, but it's a curiosity of mine. Please don't take this as an insult; it seems to be very common and as a language learner myself I'm just w…

As far as I know, punctuation association rules are the same in all indo-european languages. Most of them bind to the left and have a space to the right. Emdash, and ... have two spaces, and endash and apostrophe have no spaces. But people struggle with this. I distinctly remembering practicing this in class when prepping for matura (Slovenian version of SATs) so I guess it isn't inherently obvious to everyone.

> Emdash, and ... have two spaces, and endash and apostrophe have no spaces.

In English, Em-dashes have a couple of different uses, but in the most common use they are usually set closed (no spaces on either end), though some styles set them with a space on either end. En-dashes have one use (similar to that of em-dashes, which is used varies by house style) where they are usually set open, and a number where they are usually set closed.

Given that the rules for these marks aren't particularly consistent, or even fixed, in English, I think its safe to say they aren't consistent for the same piece of punctuation across all uses in all Indo-European languages.

Re: I was asked to crack a program in a job interview

#23

Post by Swizec »

dragonwriter wrote: post #21
Swizec wrote: post #8

Earlier quoted context omitted.

As far as I know, punctuation association rules are the same in all indo-european languages. Most of them bind to the left and have a space to the right. Emdash, and ... have two spaces, and endash and apostrophe have no spaces. But people struggle with this. I distinctly remembering practicing this in class when prepping for matura (Slovenian version of SATs) so I guess it isn't inherently obvious to everyone.

> Emdash, and ... have two spaces, and endash and apostrophe have no spaces. In English, Em-dashes have a couple of different uses, but in the most common use they are usually set closed (no spaces on either end), though some styles set them with a space on either end. En-dashes have one use (similar to that of em-dashes, which is used varies by house style) where they are usually set open, and a number where they ar…

Your description leads me to believe I confused emdashes and endashes again. Happens every time.

Re: I was asked to crack a program in a job interview

#25

Post by CocaKoala »

elektronjunge wrote: post #12
mathrat wrote: post #6

Earlier quoted context omitted.

Haha, if that's the one I remember you could completely trivialize that lab by fiddling with the program counter in gdb (skipping the line that sets off the bomb). Don't know if they were able to fix that in later versions of the lab. Good times, thanks for reminding me.

When I did that, it seemed like it was intentional. You could only get to the portions that signal success to the server by cracking parts of the bomb which was what we were graded on. The "don't let it explode" part was really the hey here's how you can use gdb to stop your program before it does anything serious.

Yeah, I thought that's how everybody did it; when my class was assigned the project, we lost half a percentage point off our final grade for each time the bomb exploded. We very quickly learned to do things like "b explode_bomb".

Re: I was asked to crack a program in a job interview

#26

Post by doktrin »

wyc wrote: post #4

This reminds me of the popular binary bomb lab offered in some computer architecture courses: http://csapp.cs.cmu.edu/public/labs.html

These are fantastic labs. I took 15-213 at CMU while already working as a software developer. It was still tons of fun and quite educational.

Re: I was asked to crack a program in a job interview

#27

Post by shakesbeard »

Swizec wrote: post #20
ar7hur wrote: post #13

Earlier quoted context omitted.

Unfortunately I think it's not so simple ";" is surrounded by space left and right ":" has no space on the left in English, but it has one in French

Nope, according to wikipedia on ";" > Modern style guides recommend no space before them and one space after. And that's really interesting about French. Personally I think a colon surrounded by spaces looks funny, but then again, I've never learned a language where that wasn't the correct way. edit: my French girlfriend says French puts spaces on both sides of all punctuation except commas and periods. Like this ! W…

Couldn't believe it myself, so I opened a French newspaper.

http://www.lemonde.fr/football/article/2014/09/17/ligue-des-...

Looks like it's indeed like she told you.

Re: I was asked to crack a program in a job interview

#28

Post by mathrat »

elektronjunge wrote: post #12
mathrat wrote: post #6

Earlier quoted context omitted.

Haha, if that's the one I remember you could completely trivialize that lab by fiddling with the program counter in gdb (skipping the line that sets off the bomb). Don't know if they were able to fix that in later versions of the lab. Good times, thanks for reminding me.

When I did that, it seemed like it was intentional. You could only get to the portions that signal success to the server by cracking parts of the bomb which was what we were graded on. The "don't let it explode" part was really the hey here's how you can use gdb to stop your program before it does anything serious.

So if I recall, you were supposed to have to do a lot of investigative work to bypass stuff. There were several different "levels" that got progressively harder to crack. But there was nothing that stopped you from moving the program counter directly to the code that signals success. Which is what we did. Every level, exactly the same: fire it up, move program counter, send the success notice, finished!

Re: I was asked to crack a program in a job interview

#29

Post by drinchev »

pkaye wrote: post #22

I don't know where you find candidates that can even approach this level of skill or desire to solve puzzles. Most people I interview struggle with a few lines C program coding.

Yeah that's why I was always thrilled with (cr|h)ackers. Back in the time when I was young actually this word ( hacker ) meant something completely different than what it is now. I think people like this have a talent in another direction, compared to programmers.

Something like : "As much as I am good in making programs I am not good at all in reverse engineering them."

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