Project Euler Returns

by garycomtois • 12 years ago

471 100 12 years ago

jonahx• 12 years ago

The decision to no longer store any private/personal information in no way reflects a lack in confidence of the steps we have taken to make the new website secure, but if history teaches us one thing it is that for every "unsinkable" Titanic built there will always be icebergs.

I love PE and I don't intend this question snarkily at all, but am genuinely curious why securing a database of emails for a site as simple as PE would be such a perilous problem? I know security in general is always more difficult that it appears, but in this case I would have thought we were dealing with a solved problem. I'd love to hear about why my assumptions are wrong.

michaelmior• 12 years ago

Unfortunately security is never a solved problem as there are always new attack vectors beings discovered. I think the statement just reflects their desire to take zero risk. The only way to do so is to avoid storing this information entirely.

Kenji• 12 years ago

Security is never a 'solved problem'. There is always a trade-off between usability, performance and security. Think of it this way: You run a server on hardware that no single human understands fully. On top of that, you have some devices for which pretty much the same applies. On top of that you have an operating system consisting of millions of lines of code, and again, nobody can fully grasp everything. On top of that, you have your webstack which adds even more complexity. You are hooked up 24/7 to a network filled with criminals.

Security is not just intrusion prevention, it's also detection and recovery. PE chose to reduce the negative effects of a successful intrusion.

Igglyboo2• 12 years ago

I'd have to agree, PE isn't a huge website and it isn't really storing sensitive data. I don't see why they're acting like it's impossible to secure their data.

parennoob• 12 years ago

The problem is clearly not simple enough that you can, say, show us a CLI two-liner which will deploy a database and frontend that are unbreakable.

Ergo, I find it quite plausible that people who are doing this in their spare time chose to avoid this task.

rmc• 12 years ago

Keep It Simple.

Not storing personal information now removes a whole class of work you have to do. While you store personal information, you need to spend time keeping on top of security patches and issues. It means you need to worry about legal obligations.

If you just don't store it, you don't have to worry about that. You need to spend less time per month maintaining the project. If you're a volunteer project, you might not have the time available to keep on top of it.

Bootvis2• 12 years ago

I have been curious for a while:

What is in the opinion of the HN community a good score on Project Euler?

For which scores do you tip your figurative hat?

Igglyboo2• 12 years ago

I'd say 100 solved problems is pretty impressive. I have about 75-ish done with no math background (other than a few classes for my CS degree).

The first 50 should be doable for most people in my opinion. After that you need to start being really clever or actually going and researching the problem at hand.

ionforce• 12 years ago

For which people?

There are certain "developers" who can't even fizz buzz their way out of a paper bag.

sejje• 12 years ago

I did the first 50 problems, and then cherry picked another 15 or so.

At some point the math was beyond my knowledge, and I didn't find much fun in researching it.

I'm a fairly normal web developer, in my own estimation.

prezjordan• 12 years ago

It's really tough to say. Some people have awesome math degrees, some people only do it casually, some don't do it at all.

Keep doing the problems until you get stuck. Then learn, then solve a few more. Repeat as long as you're happy with your progress. I wouldn't put a number on it.

In fact, do some easy ones in a completely new language!

neutronicus• 12 years ago

Not scores so much as specific problems.

If I work on it for a week, get frustrated, google for solutions, and can't find any, and you solved it, you're a beast.

Also if you solve 328 tell me how. And no, dynamic programming is not efficient enough.

andreasvc• 12 years ago

Maybe there is a closed-form solution?

ghusbands• 12 years ago

It's easier than you might think. Only read this comment as far as you need to make a little more progress. These hints only apply if you're starting with a dynamic programming approach. Also, they're only helpful if you do the work, so I don't think they violate the spirit of Project Euler.

Is your dynamic programming table 2D? Maybe it should be.

Stop reading if that's progress.

Have you looked closely at the table content?

Stop reading.

Have you noticed how similar many parts are, under perhaps simple transforms?

Stop reading.

Try adding or subtracting your coordinates, to see more of the pattern.

Stop reading.

There's not just a within-row pattern.

Stop reading.

In the end, dynamic programming might not be the main trick. But you can make your own way from here.

philbarr• 12 years ago

As far as I'm aware, Project Euler doesn't make any actual money, so you have to give the team behind it a lot of kudos for actually taking the time to get it back up and running.

Must have been really tempting to just sack it off as a bad job. Congrats to the team!

n8m• 12 years ago

Agreed! Well done guys!

kbar132• 12 years ago

it would be great if PE was open source :)

arikrak3• 12 years ago

Anyone interested in creating an open source version? It could have more features - such as running the code online, and more topics - such as non-math challenges.

burkaman• 12 years ago

It's not open source, but https://www.hackerrank.com/ sounds exactly like what you're describing, in case you've been looking for something like that.

kbar132• 12 years ago

I think that would be an interesting problem itself. Does PE export its problems & solutions in some kind of easily consumable way?

arikrak3• 12 years ago

I created http://www.learneroo.com which lets people solve programming challenges (and other challenges) online. It's not currently open-source, though if there was interest I would consider open-sourcing it. (I would first need to clean up some code that I didn't think anyone would see!)

hyperpape4• 12 years ago

I should preface this by saying that I love Project Euler--I spent a ton of time there while learning to program. I also am impressed by anyone who volunteers to create something for the community, and invests effort in maintaining it.

However, not storing emails, and thereby giving up account recovery with the explanation that it's about security is a shit sandwich.

My email is <myfirstname>.<mylastname>@gmail.com, a pattern I share with millions of people. This is public information. I could spray paint my email address on local bridges without in any way making my email less secure (cops might complain, though).

I understand that some people have reasons to have private email addresses that they don't want released (they'll give them to family, but not the general public). They should never sign up for anything with those email addresses, because the moment you sign up for things, you will almost certainly be entered in a database somewhere, and eventually be spammed or subjected to whatever other bad consequences you're concerned about.

Account recovery is a basic feature of a website (except those that contain data too sensitive to have account recovery), and they're giving it up for phantom security.

pgeorgi• 12 years ago

The combination of email address + password (even hashed in some way) isn't quite as public anymore.

Not having any personally identifying information doesn't protect your Project Euler account, it protects your other assets.

tormeh• 12 years ago

Hm... Couldn't you just sign in by using only your email without any password or any other extra stuff? I mean, it's not like there's any sensitive information there. Could lead to some trolling, but I think trolls and Project Euler don't have much overlap. In some cases I think it's valid to ask "why security?".

mikeash• 12 years ago

I think this is the key point. Security for relatively obscure and unimportant sites isn't really about those sites, it's about other sites. People reuse passwords a lot. They shouldn't, of course, but you can shout that from the rooftops all week and it won't change the fact that a lot of people do. If you suffer a significant breach, then a decent percentage of users will have their bank accounts put at risk from it. You can simply put the blame on the dumb users who reused passwords, but it's reasonable to want to do more.

hyperpape4• 12 years ago

This is a good point, and a reason to do the right thing with regard to emails--which is to store a safe version of them (bcrypt).

Because while an email and a password is not public information, a username and a password isn't public information either. If you don't trust yourself to store the former, you shouldn't trust yourself to store the later much either.

bellerocky3• 12 years ago

"Account recovery will no longer be possible."

A site that purports to teach is incapable of learning of how to strike a balance between securing confidential information and making it possible to recover an account. This is a solved problem. If my bank can have a password recovery system, a site about numbers can have one too.

" With respect to this issue it is quite possible that some members will have genuinely forgotten passwords."

Who hasn't "genuinely" lost a password?

taeric3• 12 years ago

To be fair, your bank likely has a bit more money to throw at this problem.

I would think in this case the entire point is not so much to help them secure stuff, but an attempt to remove them as a target for hacking in the first place.

ntpl3• 12 years ago

It's one thing to decide not to store emails (sure, why not?) but account recovery shouldn't even require one to store email addresses.

Check the the email provided by user via the recovery form against a hash of the email saved during registration, if it matches send the reset link. This way when data is breached, figuring out what the original email should be hard (if not impossibly hard, depending on how they hash it).

Am I missing something here?

vog2• 12 years ago

You should not simply use a hash, but at least a salted hash, or even harder stuff like bcrypt. In other words, treat emails like passwords.

Apart from that, I don't see any issues with that approach. Not sure why project euler doesn't use that approach.

hyperpape4• 12 years ago

Of course you're right, and I can't believe I didn't realize that. I think my point still stands that it's a bit silly to worry about storing emails, but you're right that you can even avoid that risk by encrypting them if desired.

(And "hash" is a bit misleading: http://codahale.com/how-to-safely-store-a-password/).

ics• 12 years ago

[...] because the moment you sign up for things, you will almost certainly be entered in a database somewhere, [...]

Oh, you've lost the game long before that. Grandma's email chain? Welcome to the database as soon as anyone on that list gets their email compromised. Apologies to all the grandmothers out there who know how to use the BCC field.

ZacharyPitts• 12 years ago

Well, I'm glad I have a git repo of all my solutions, so I can get back up to my original 102 problems solved. And then go back to not doing it again because it is too hard now.

mathattack• 12 years ago

Glad to see them back!

hardwaresofton2• 12 years ago

If Project Euler is trying to make itself less interesting to hackers/less vulnerable by storing less information(email), why don't they consider OAuth for login?

I know OAuth has it's own warts, but isn't part of the point to offload the burden of authentication to someone else?

Also, feel free to replace OAuth with Mozilla Persona or OpenID.

[edit] - s/storing less password/storing less information\(email\)/

hardwaresofton2• 12 years ago

Also, I've been thinking of this for a while, but Project Euler needs to be open-sourced. I think this would help people who don't necessarily want to contribute money. I thought rather than just making suggestions, I could make a pull request for implementing OAuth/Persona/OpenID login -- then I realized it wasn't open source...

I've been keeping this idea close to the chest, mostly because it's something I want to do, but Project Euler could easily become a great training tool, an easy-to-install packaged django application(I mention django for it's nice out-of-the-box admin interfaces, doesn't matter what it is as long as it's easy to manage for admins and users)

curiousfab• 12 years ago

Who returns, Project Euler?

Neither the news page, nor the "about" page, nor the front page of "Project Euler" care to explain what this website is all about. Of course, I can guess that it has to do with mathematical problems of some sort.

It is sad if you have to turn to Wikipedia to find out the basic details about a website. A sentence or two of introduction would have made everything better :-)

doodpants• 12 years ago

The site used to have a front page that clearly explained what it was all about. I assume that it will be restored along with the rest of the functionality on Saturday.

ohitsdom• 12 years ago

Agreed, I had never heard of it and the about page was no help at all.

gknoy• 12 years ago

On the off chance that other comments here haven't made it clear what it's about, or that you haven't already looked it up, they apparently have a Wikipedia article about them:

http://en.wikipedia.org/wiki/Project_Euler

""" Project Euler (named after Leonhard Euler) is a website dedicated to a series of computational problems intended to be solved with computer programs.... Problems are of varying difficulty but each is solvable in less than a minute using an efficient algorithm on a modestly powered computer. A forum specific to each question may be viewed after the user has correctly answered the given question. """

There are also several Github repos out there that have both the problems and hashes of the answers. (Some have the actual answers, as well, or used to in the git history, but presumably anyone interested in solving the problems is more interested in the process than the score.)

asgard1024• 12 years ago

I wonder if the people behind Project Euler have names or it has all been done by this prolific guy Bourbaki?

Xophmeister• 12 years ago

Bourbaki was a French collective of mathematicians, working/publishing together pseudonymously. I would therefore guess that the same kind of structure is in place at Project Euler: It's not one guy, but a joint effort operating under one name.

EDIT: https://en.wikipedia.org/wiki/Nicolas_Bourbaki

zerr• 12 years ago

Btw, anyone has a list of subset tasks on this Project Euler more related to pure CS/Algorithms rather than Math? Preferably mentioned the level of experience. So far, as I can see, it is aimed for very beginners, right?

rqebmm• 12 years ago

What is project euler? The "about" page has lots of helpful information about submissions and scoring, but nothing ABOUT what it is!

scott_karana• 12 years ago

They're programming/math quizzes (puzzles?), which you submit for automated testing.

jleader• 12 years ago

It's a site full of problems, which generally require some mixture of math and programming skills to solve. You can trade off between the two. If your math is good enough, some problems can be solved with pencil and paper. If your programming is decent, some can be solved by brute force search. There's no time limit, you don't show anyone your code, you just type a brief answer into a text field, so the only constraint on the efficiency of your code is how long you're willing to leave it running.

It's a lot of fun; the math involved can get pretty advanced on some of the problems.

rikkus• 12 years ago

I created an account but couldn't log in. As I've had the same happen before, I tried using only the first 32 characters of my password when logging in. That worked.

Remember kids: Most software development isn't about puzzle solving and algorithms, it's about making stuff like forms work properly.

Of course the puzzles and algorithms are fun, which is why I'm signing up for PE again!

Project Euler Returns

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