OJ Board

There's an O(n log n) algorithm for this.

Super-fast times are usually I/O optimization or tables or something like that. Don't worry about it.

Easy ones.

No.

Use C.

Go to cygwin.com, click on the setup thingy.

n^2 log n is way too much. I did this in the contest in three minutes, with 34 lines. I think that the problem setter did not intend for an n^2 log n algorithm to be acceptable.

In Rocky Moutain Regionals, we had the full API from a link on the desktop, and there was a FAQ entry giving a full solution to one of the practice problems in Java, so that you could see how to do the File I/O.

It took us longer to get a test Java BigInteger sample to work at the practice than to ...

I don't believe you. I've done the same thing, where I was convinced the input was wrong, that all I had to do was change one line in my input routine to go from WA to AC; but I contacted the people who run the judge, and they checked, and the input was fine.

If there really is a problem, email the ...

I highly doubt that the input is incorrect. If you email problemset@acm.uva.es, they can check it for you, but at least 93% of all such claims are absurdly false.

I have not read your code or post, but there is an O(n log n) dynamic programming solution for this problem, which uses linear space.

Do you know why it is a special corrector problem?

Your integer compare is stupid. If the two numbers are equal, and you add 1 to each, they will still be equal.

Just do return *(int*)a-*(int*)b; to sort in ascending order.

You have a function best(int n,set of intervals). If the given set of intervals covers the 0th through n-1th numbers, then best(n,set of intervals) is the minimum, over all intervals (call each one I in turn) containing the nth number, of best(n+1,set of intervals \[Union] I).

best(int n,set of ...

I have not done the minimal set problem, and have only thought about it for two minutes, but here is how I would do it

Have a function
best(next number to consider,chosen set of intervals)
= minimum over all intervals I that cover the next number to consider, of best(next number to consider+1 ...

I blame that fact that it is open source software, which we all know is crap.

I'm glad you have made a post about 10265--that it can be found by looking for 'toroidal'--and that your post is found when searching for 10265.

I have experienced similar things with this lousy php software many times ...