OJ Board

Problem statement says "Input consists of a number (>0) of problems. " (i.e. number of test cases). Sample input does not

bolster

thanks =)

No definition of non-binary bracketing was given.

please clarify, thanks.

bolster

Hi,

I am trying to brush up on my Prolog, and was wondering if anyone knew of any problem set archives online that are designed for logic programming. Thanks a lot.

bolster

Hi,

I was just curious - What is wrong with the CII page? When trying to access for the first few times, I get "Internal Server Error," and then it gets fixed. This only happens for CII. I have reproduced it on more than one computer (in different cities, for that matter hehe).

thx

boldter

Woohoo I got AC! =)

it really WAS the new line thing... missed it i guess... i'm surprised it didn't give me format error though. thanks

I'm getting WA for it too... it might be because of the way I do the output...

they say you can use a-z, but I only actually use a-f (cause you don't really need the others... the neighbours are still ok)


bbccddbbddbbddbbddbbddbbddbbddbb
baacdaabdaabdaabdaabdaabdaabdaab ...

Ah I remember that one. I believe it was from the CCC in 2000, correct? You can solve this using dynamic programming.

Place a ball at the start. Now, note that from this point, the ball can go to 32 locations... label each of those locations with "1" since it takes one swing to get there... Now, go ...

No, I'm using C... It's kinda funny... I got AC on 10178, so it's probably just some annoyingness that has been done to the input... Sometimes, it's all in one block, sometimes there's a space... completely inconsistent input *snicker*

Are there any degenerate cases to worry about in this? I keep getting WA, for no apparent reason. Are there mysterious multiple test cases or something?

fyi:

Here is what the problem was (it had nothing do to with hull):

1) you have to worry about the case where several points are colinear (aa is zero)

2) Sometimes, "-0.000" is probably displayed for small numbers that get rounded off, so must add some small value to all output.

b

Generate the first 70,000 or so primes, and use those, combined with a sieve.

Alright =)

I'll get to work on that later, thanks. (heh I hate geometry problems... In many cases, it's always some stupid meaningless roundoff error from doing the calculation in a different manner... they should allow a +/- 0.005 or something )

I thought about finding the convex hull first, but since it's a convex polygon, it shouldn't matter. If you find the lowest point in the set, and sort the others in increasing polar angles, with respect to that lowest point, then since it's convex, you will have the points in counter-clockwise order ...

Hi,

What am I doing wrong here?

1) Find point of lowest 'y' coord
2) sort the other points according to polar coordinates (angle), relative to the first point
3) Apply the following algo:

a = cx = cy = 0;
for(i=1; i < n-1; ++i) {
aa = cross(p[i].x-p[0].x,p[i].y-p[0].y, p[i+1].x-p[0].x,p[i+1].y ...