My Piece of the Inter(.)net » C Plus Plus

New and improved! The previous post on one line!

David McGrath — Tue, 20 Oct 2009 20:13:33 +0000

This following bash code outputs the puzzlebot facebook email from my previous post with no extra output. This is one of those “just for fun things” that non-CS people don’t understand.

echo -e "#include \nint main(int argc, char ** args){printf(\"%d@facebook.com\\\n\", 0xFACEB00C>>2); return 0;}" > fbmail.c; g++ fbmail.c -o fbmail; ./fbmail; rm fbmail.c fbmail

http://facebook.com/puzzles

David McGrath — Tue, 20 Oct 2009 19:53:10 +0000

I had a preliminary interview with a woman at Facebook yesterday. We scheduled another interview for Thursday, which will have more technical kinds of questions. I asked her what i should be doing in the interum,and she suggested that I check out http://facebook.com/puzzles. The page had brushed past my radar in the past, but I didn’t give it a serious look until now. The page has a bunch of programming puzzles for anyone to do. Even the submission email address is a puzzle.

Submissions should be sent via email to the address: {0xFACEB00C>>2 in decimal}@facebook.com

Since one can easily find the email with a quick Google search, I thought I’d show how to find it. The puzzle page is Unix-centric, so for this task I logged into an Ubuntu virtual machine that lives on my home network.

In ViM, here’s the simple program:

cute. I have saved the file, and now I write a command to compile and execute the code.

And now we see the output of the email (below “[. . .]vim fbemail.c” and above “Press ENTER [. . .]“)

Yeah, no spoilers here… but if you can’t complete this task you won’t be able to do any of the others anyway. No doubt the Facebook recruiters will judge me on my performance with these. This is going to be fun.

edit at 4:25pm: update

FRI is dead, but its spirit lives on

David McGrath — Mon, 12 Oct 2009 04:01:38 +0000

It’s been almost a year since I’ve updated FRI, my ROM library program. FRI is now officially dead, but not completely gone. Since I started working on FRI I have gained a lot more programming experience. I started writing the thing when I was still a C# novice. Between then and now I have written an elaborate intranet site in ASP.NET, debugged and written C++ applications, and have learned the true value of a regular expression. I look at FRI’s code now and am a little grossed out. I decided that if I was going to make any more improvements to FRI, I’d have to start over and rearchitect the whole thing. The name of this new project: Arcadia.

With Arcadia I have committed to research everything that I suspect will make for a better design. Because of this, Archaida’s backend is shaping up to be elegant and efficient. I researched how to do inheritance in C#, and have used that to save myself from writing a lot of code. This has drastically decreased development and testing time. I learned how to use basic regular expressions over the summer, and have used them in some areas (more on that later). For the frontend I decided to switch from WinForms to WPF. All I can say is that databinding is epic, and I still have a lot more to learn about it.

Here’s a shot of Arcadia in its current form:

I’ll hopefully release an alpha soon.

edit October 12, 2009 at 10:57am:

Also generics. Generics are amazing. (More on that later, too.)