If it is something to use in an educational setting, even a non-traditional one it would likely be welcome. You can also write it up first on our sandbox area and get some feedback before it goes live.

Write it up as an "answer" here: cseducators.meta.stackexchange.com/questions/202/…

It will then "magically" show up here in a few minutes. Ordinary CS might be better than SO, I think, but here would likely work out.

Also, the ACM SIGCSE has a mailing list for members that would likely be a good source for resources. Some of the members here are also members there, but I think not many.

The point of this resource is to avoid having to reinvent the wheel every single time you try to make a programming exercise and want to test potential solutions automatically. E.g., every time you write a programming exercise whose solution is intended to use Dijkstra, you can fit the collection of graphs into the correct specification, without having to think of possible problems anew and anew. However, it's not so much for use in the classroom as it is for use in programming contests.

(Of course these things need not be mutually exclusive.)

Err, and to really get at the purpose of my question: I'm thinking of creating a resource like that (with a few others), but wouldn't need to if it already existed (or it would give me something to build on).

@MeesdeVries IIRC, someone categorized the Project Euler problems by algorithmic type.

That's all I've got.

Hey @GypsySpellweaver Do you still exist?

Nope.

@HenryWHHackv2.1 That's not comforting.

Last seen 9 hours ago

Last seen 7 days ago on his network profile.

Speaking of old friends that I miss, we also haven't seen @Aurora0001 or @EllenSpertus in awhile. @heather came in for a bit today. That was nice :)

Whoa, speak of the rocket, and there she is :)

Nice picture, Henry.

No one answered my conducting question on music.se :( (music.stackexchange.com/questions/64353/…)

to answer your earlier question, my classes are algebra II, spanish II, honors english I, whatever standard social studies class, physical science, intro to engineering, and health/p.e.

@heather I'm guessing that the math class is pretty easy for you. What is your favorite course so far?

I'm guessing it's not "whatever standard social studies class" ;-)

@BenI. yeah, the math's pretty easy. it's all pretty much review. the teacher brought in some finite mathematics textbooks that me and a friend are working through, which is fun - the simplex method is cool, for instance. engineering is probably my favorite.

@BenI. lol, nah.

What is the "simplex method"?

are you familiar with linear programming?

I was about to guess that honors english was going to be your favorite

@heather Nope

@BenI. the teacher is pretty cool, honestly. it'd probably be my second favorite class.

she's got a ton of books too, which is nice.

@BenI. okay, so basically, say you have a problem where you have a system inequalities and you want to find the vertices of those inequalities.

@BenI. en.wikipedia.org/wiki/Simplex_algorithm. I used to work with Dantzig's son.

this is useful for many reasons - think, you have so many constraints and you want the max/min values to plug into a function for, say, profit.

@heather You might have to break this line down a little further for me

@Buffy Well, I still like dancing to this day! ;-)

Dantzig himself died only a few years ago. One of my student's grandfather did similar work independently in Russia.

Ooh, that would have been a much better line to respond to with that pun.

I missed my chance

okay, so let's say i have a problem like: i have 10 hours of metal working labor time, 10 hours of wood working labor time, toy trains take 1/2 hr of metal working time and toy trucks take 1/4 hr of wood working time; i get $10 profit for a toy train and $5 for a toy truck; how many of each should i make to maximize profit.

if i assign the variable x for # of toy trains and y for # of toy trucks

i can do the following inequalities:

1/4y <= 10, 1/2x <= 10, x >= 0, y >= 0

and the function:

f(x, y) = 10x + 5y

basically, i want to figure out how to still satisfy the constraints (inequalities), i.e., be in the "valid region", but still maximize the value of the function.

is this making sense so far? I'm bad at explaining things.

No, so far that is very clear. You're doing very well.

okay.

so, each point a pair of inequalities intersect is a vertex, and these vertices define the "corner" points - they're the only values we need to plug into the function.

so i can solve each pair of inequalities for those vertices, plug it into the function, and figure out which values maximize the function, and i've got my answer.

however, this is only with two variables.

So, what would the vertices be for those inequalities?

(I guess I'm not sure what you mean by "intersect" here)

hmm, i just made that problem up, so i have no idea if it's going to work out.

LOL :) Fair enough :)

well, what i mean by intersect is, if i graph those inequalities

i'm going to basically have the x and y axes, two other functions, and a shaded region in the middle that's defined by the "corners" - the spots where the functions intersect with the x and y axes, and the origin.

qph.ec.quoracdn.net/main-qimg-79e5594011fb2a1a2fe4dc01919ced2a

^see for example that image there.

those points marked with the large dots are the vertices (plus the origin, but i think it's obvious that's not the maximum profit we're looking for).

so, that's in two dimensions. in three dimensions, though, it's not nearly as easy. the simplex method is a way to deal with it.

let me think how best to explain the simplex method...

What would the purple line represent in a picture like that?

@BenI. one of your inequalities. ditto for the blue and green lines.

the simplex method, to oversimplify, is basically writing all the coefficients of your function/inequalities in a matrix and then using row operations to find the optimal solution. i'm still learning it so i don't know if i can describe it much better than that right now.

Huh. That's quite clever.

(I suspect that your explanation is about as much as I wanted to get out of this right now anyway)

Thank you!

With @HenryWHHackv2.1 here, heather, and Buffy, it feels a bit like it used to :) Now we need @ItamarG3 and one or two others to be totally back.

Oh, and we need a random argument to break out. Probably with @thesecretmaster as the bad guy, and Heather to defend him. (Because, at the end of the day, he's really right.)

This room isn't what it use to be.

Maybe not, but it's still a very good room. And more active than the chatroom of a lot of sites.

Hey @heather, how active is this room compared to Physics?

Blah, I have to get back to work shortly :(

less active than hbar for sure, especially because most users here are in the same time zone.

a heck of a lot more active than other chats though, for sure.

@BenI. np! it's fun explaining stuff like this. helps me understand it better anyway.

Glad to be of service! ;-)

Only three users are in the room now.

And one of them is doing work.

@BenI. DOWNVOTE MOAR THINGS

Aw, everyone left before I got here :(

I am here to hold down the fort.

@BenI. Objection

@thesecretmaster MORE*

@heather I understood the reference (as in, Higgs bar, which doesn't exists as far as we know, as so is totally inactive)

@heather, just started working with one of the people who made the BaBar experiment.

@ItamarG3 Hmmm. You haven't kept up with zombie culture. MOAR BRAINZ!

News Of The Day: I got a outspoken badge.

I used to spend a lot of time outspoken, but I'm too old to ride now. My bicycles have gone unused for quite a while.

@ItamarG3 The h bar is the Physics chat room, in case you didn't know.

@Buffy What do we want? Braaaainnnzzzzz

When do we want them? Braaaainnnzzz

Another interesting (if disturbing) article. This time from IEEE Spectrum on how women have faired in the industry. spectrum.ieee.org/view-from-the-valley/at-work/tech-careers/…

@thesecretmaster I did know that. But it is amusing for a second reason...

@BenI. Thanks for thinking of me. I'm pretty busy nowadays with this: techintersections.org

I'm managing most of the data, including the website, and the logistics (caterers, space, childcare, sponsorships, email, program, etc.).

Good job. How many tech meetings even think of providing childcare? Not many, I'm pretty sure.

Lots of Lego Mindstorms kits maybe.

@EllenSpertus Any way that we can help out?

Not exactly the same, but you could make colleagues, students, teachers of your acquaintance aware of of the meeting if they might be interested.

@BenI. No, but thank you.