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Ask HN: What's the hardest problem you've ever solved?

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Re: Ask HN: What's the hardest problem you've ever solved?

#251

Post by austincheney »

oldandtired wrote: post #242
austincheney wrote: post #133

A simplified universal parsing format (AST) that equally describes all languages. It needs to allow seamless switching between different languages in the same file and also allow recursively nesting of different languages within each other without resulting in a deviating from the simplified parse format. The solution is written and it appears correct and viable. As in all things related to parsers the devil's in the…

Does this handle languages like Icon or Unicon in which the concept of "failure is always an option"?

I honestly don't know. I have only written lexers, the part that does the analysis, for a few languages. The output format is completely language agnostic though. Go read through the docs or play with the demo to see what the output format looks like.

Re: Ask HN: What's the hardest problem you've ever solved?

#252

Post by yesenadam »

yholio wrote: post #90

I somehow decided I needed to cheat to pass a certain exam because I was basically crap at memorizing stuff. So I used an analogue wireless headphone, an induction loop around my neck and a mobile phone. Since I lacked an accomplice to dictate, I read aloud the hundreds of pages and recorded myself, careful to preserve and properly serialize things like complex formulas. This was before the era of iPods and SDCard pl…

You rejected ethical behaviour 'on principle', you even seem proud of that. Have you kept doing that in life? Do you feel like an impostor, presumably with your degree that you didn't think you could acquire without cheating, or couldn't be bothered?

A surprising number of the replies to your comment also seem to think cheating like that at university is perfectly fine.

Re: Ask HN: What's the hardest problem you've ever solved?

#253

Post by xiphias2 »

red75prime wrote: post #245
yholio wrote: post #90

I somehow decided I needed to cheat to pass a certain exam because I was basically crap at memorizing stuff. So I used an analogue wireless headphone, an induction loop around my neck and a mobile phone. Since I lacked an accomplice to dictate, I read aloud the hundreds of pages and recorded myself, careful to preserve and properly serialize things like complex formulas. This was before the era of iPods and SDCard pl…

That's quite impressive setup. I've used programmable calculator with text storage capability for my chemistry exam. I was correct that I will not need chemistry knowledge in all my life.

I was also cheating on my chemistry exam, but as your life is over yet I wouldn't be so sure. As I'm getting older it's getting more and more important for me to understand the biochemical processes that are going on (or going wrong) in my body.

Re: Ask HN: What's the hardest problem you've ever solved?

#254

Post by alxlaz »

twtw wrote: post #146
StavrosK wrote: post #141

Earlier quoted context omitted.

There's more to learning than memorization.

There's more to exams than memorization too, and cheating because you don't like memorization is childish. If the exams really test only memorization, drop the class.

I'm not defending what they did, but it's worth pointing out that electives aren't exactly universal. During my university I was allowed to choose exactly 4 classes out of 6, in my last semester. Every single other course was compulsory. I never cheated, and looking back on it I'm glad I didn't, but I certainly did my share of useless learning.

Edit: that being said, in a system where there is such a thing as non-compulsory courses, and the critical path to graduation is sane, cheating on an exam on the critical path should definitely not be acceptable, even if it's "only" memorization. Some things really do need to be memorized.

Re: Ask HN: What's the hardest problem you've ever solved?

#255

Post by dempseye »

Cyph0n wrote: post #67
uxcolumbo wrote: post #62

Earlier quoted context omitted.

How did you approach this problem and solve it?

Not OP, but it seems like Electrum maps the wallet seed to standard English words. The other thing that helps is that the redaction isn't complete. So what I would do is: 1. Estimate the possible locations of spaces (e.g., using OpenCV). 2. "Guess" certain letters based on what is visible above and below the black bar; these are your constraints. 3. Look up dictionary words that meet the constraints found in (2). 4.…

Yes, it's a monospace font. The start, end and pattern of visible ascenders behind the redaction, along with the word list in electrum would allow you to reduce the search space by a lot, I suppose.

Re: Ask HN: What's the hardest problem you've ever solved?

#256

Post by brianpgordon »

yesenadam wrote: post #252
yholio wrote: post #90

I somehow decided I needed to cheat to pass a certain exam because I was basically crap at memorizing stuff. So I used an analogue wireless headphone, an induction loop around my neck and a mobile phone. Since I lacked an accomplice to dictate, I read aloud the hundreds of pages and recorded myself, careful to preserve and properly serialize things like complex formulas. This was before the era of iPods and SDCard pl…

You rejected ethical behaviour 'on principle', you even seem proud of that. Have you kept doing that in life? Do you feel like an impostor, presumably with your degree that you didn't think you could acquire without cheating, or couldn't be bothered? A surprising number of the replies to your comment also seem to think cheating like that at university is perfectly fine.

It was undoubtedly unethical behavior. But it's like... well it's like the story of Toshihide Iguchi, who accumulated over a billion dollars of trading losses and hid them successfully for 12 years. Sure you throw the guy in prison, but you have to hand it to him that what he managed to do is pretty damn impressive. After his release, finance CCOs might even want to hire him to audit their traders.

You can get off your high horse about not being able to acquire your degree without cheating, too. I never once cheated at any point in college, but if I had spent more time working on sick electronics projects and less time memorizing the years of significant 15th century battles, I'd be more qualified technically, not less. The ethics of it are problematic as I've said, but you seem to be going farther and implying something about his ability as well.

Re: Ask HN: What's the hardest problem you've ever solved?

#257

Post by bobosha »

herodotus wrote: post #197

When I was a CS prof, many, many years ago, our undergraduate lab had Macs with floppy disks. I asked the University to pay for installing 10MB Hard Drives in the Macs. I was asked to present my case to the deans council. At the meeting, I said that the students used the floppy to load their development environment. I said that, with a hard drive, it took 10 secs to load and be ready. With the floppy, I said it took…

> When I was a CS prof, many, many years ago,

Curious what you do now.

Re: Ask HN: What's the hardest problem you've ever solved?

#258

Post by TomMarius »

devcpp wrote: post #204
killjoywashere wrote: post #175

Earlier quoted context omitted.

> Admitting to significant ... fraud during a job interview is a very, very bad idea. After serving his time, that's exactly how Frank Abagnale got a job in the FBI. https://en.wikipedia.org/wiki/Frank_Abagnale

Well, you need criminals to outsmart criminals. I'm not sure why you need that trait in software. You're (usually) not trying to beat other programmers. So I suppose the parent comment should have added "except in adversarial situations". Which means it does apply to cyber security. You need hackers to outsmart hackers. If that's the kind of industry you're applying for, it probably is a good idea to mention this act…

Many EU startups won't be interested in your academic records but such a project would make them hire you on the spot.

Re: Ask HN: What's the hardest problem you've ever solved?

#259

Post by quadcore »

yesenadam wrote: post #252
yholio wrote: post #90

I somehow decided I needed to cheat to pass a certain exam because I was basically crap at memorizing stuff. So I used an analogue wireless headphone, an induction loop around my neck and a mobile phone. Since I lacked an accomplice to dictate, I read aloud the hundreds of pages and recorded myself, careful to preserve and properly serialize things like complex formulas. This was before the era of iPods and SDCard pl…

You rejected ethical behaviour 'on principle', you even seem proud of that. Have you kept doing that in life? Do you feel like an impostor, presumably with your degree that you didn't think you could acquire without cheating, or couldn't be bothered? A surprising number of the replies to your comment also seem to think cheating like that at university is perfectly fine.

My humble opinion. University is about learning (not, for example, status). Learning is something strictly personal. There is nothing fundamentally universally wrong to cheat at an exam beside the fact you may be harming yourself.

Now since we need a little order for various secondary reasons, we promoted exam cheating to illegal and that's ok. We need order. But there is nothing someone should feel guilt for imho, assuming the person knows she may be harming herself.

Re: Ask HN: What's the hardest problem you've ever solved?

#260

Post by ak39 »

KuhlMensch wrote: post #250
herodotus wrote: post #197

When I was a CS prof, many, many years ago, our undergraduate lab had Macs with floppy disks. I asked the University to pay for installing 10MB Hard Drives in the Macs. I was asked to present my case to the deans council. At the meeting, I said that the students used the floppy to load their development environment. I said that, with a hard drive, it took 10 secs to load and be ready. With the floppy, I said it took…

This is the best thing I have ever read on HN

I was going to say the same thing. We really need a HN hall of fame for many of these types of comments. Pure gold. Made my Sunday.
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