OJ Board

Hello everyone, We would like to invite all of you to take part in IPSC 2009 -- one of the oldest (11th year), challenging and entertaining online programming contests. The contest will take place at Saturday, May 30 2009, start at 14:00 CEST (GMT+2) (click the link if you are in a different time zo...

Not that you'll ever need this on an ACM ICPC contest, but for the sake of completeness: maximum number of points on a line can be done in O(n^2) by using the point-line duality, and then traversing the plane subdivision and looking for the vertex of maximum degree.

If you submitted your solutions as plain C, then the missing "return 0" could indeed be the problem -- in that case your main function just returns whatever it finds on the top of the stack (which is most likely not zero). From the judge's point of view, your program's exit code was not zero, thus y...

There's more to difficulty than a linear scale can show. For example, the average number of submits a user makes before getting AC somehow measures how "tricky" the problem is.

Have you seen http://boost.org/ and possibly also http://algorithmist.com/ ? Maybe contributing to an existing project makes more sense than starting your own -- this is not a task for one man. Oh, and there is an asymptotically more efficient algorithm for all-pairs shortest paths. I'm not sure abo...

One mistake I see is that the "j" in your "jolly" is lowercase but should be uppercase.
Learn to always test your solution against the example I/O before submitting

Edit: Also, change the exit(1) to exit(0), your program is supposed to terminate normally under all conditions.

We would like to invite you to the 2007 Internet Problem Solving Contest. The Internet Problem Solving Contest (IPSC) is an online (mostly) programming contest for individuals and teams of up to three people. Its purpose is to challenge programming and problem solving skills of people around the wor...

I don't see a reason why it should make multiplication significantly slower.

If you can only do one assignment in one statement, it seems impossible -- after the first assignment, one of the variables is unchanged, the other has to have the new value, and thus one of the values is lost. I think we need a more precise definition of what those "two statements" are allowed to b...

The third argumet of qsort is supposed to be the size of a single element, not of the entire array.
In this case, sizeof(data[0]), or equivalently sizeof(tdata);

I thought it was rather... umm... "amusing" that Top Coder puts Visual Basic on the same footing with Java, C++, and C#. They also have a very limited selection of languages. The reason for including VB at TopCoder is that it's simply another .NET language, so adding it once they had C# required al...

You may be interested in a similar site that already supports Python: http://www.spoj.pl/

Do you know what a Voronoi diagram is?

WTF UCS? UTFG? Honestly, I don't have a clue what your UCS means or should do, and neither does Google. The algorithm must have a more proper name (e.g., are the UCS initials of its authors? an acronym of the method used?). If you know that, try googling for the long name. I doubt someone will be ab...

For other readers of this thread, this is the problem statement: http://acm.timus.ru/problem.aspx?space=50&num=9 Instead of copying it you could've linked it. I still had to google to find it, without the images it was hard to understand. As for the solution, the brute force search can be pruned as ...