Ccc 2012

[Advecticity]

What are your opinions on S4 as a contest question in general? A problem that involves a straightforward solution that works for n = 7 but that would likely fail for n = 9 or something seems to just invite dirty solutions.

Unless the solutions that the people that solved S4 came up with are different then what I have in mind.

[Yves]

The last case for #4 was surprisingly easy; my extremely slow solution just passed with 49 seconds on my computer, so I tentatively have a perfect. (:

[ihsh]

Yves @ Tue Feb 28, 2012 8:54 pm wrote:

The last case for #4 was surprisingly easy; my extremely slow solution just passed with 49 seconds on my computer, so I tentatively have a perfect. (:

The test-cases are out to the public already?
If so, could you tell me where I could find them? Thanks.

[Drenn]

I did 1-3 relatively quickly. My solution to #3 started working before I expected it to... which is really weird... I hope it works in all test cases. I spent the rest of my time on #4 expecting #5 to be way too hard for me. After giving it a closer look I realized it was far easier than I thought! Oh well. I couldn't get 4 and didn't have the time to start 5.

[Snario]

DanielKang @ Tue Feb 28, 2012 7:11 pm wrote:

Hello, I did the junior one, and the same problem appeared as J5.
Thankfully, after rocking my head trying to figure out how to do it, I was able to successfully analyze each case then use println.
Notice that for S4, n<8, while in J5, n<5, which made manual work possible (33 cases).

Can I get full marks with this approach? Where I just do the calculations by hand and just print the results out for each case?
If I do, then I have high chance of getting 75/75 which would be awesome considering this is my very first compsci competition.

Same here.

Was it just factorial business? I didn't see a pattern

[crossley7]

it wan't just factorials. n! is the number of possible inputs for input of size n but other than that I don't think the result had anything to do with factorials. No simple math that you could do to solve.

[d310]

I also got perfect!
I do think that problem 5 should have been much harder.

[mirhagk]

So I see 3 perfects here.... and a couple more that probably did better than me.... Dang looks like me 4.2/5 problems just ain't going to cut it.

[crossley7]

I'm hoping that 4.5/5 will work (although that depends based on test cases for 4. May be higher/lower if they like 6 and 7 that have solutions) I just output impossible for 6 and 7 because it took my program too long to compute.

It will be frustrating for me not knowing my score until last period at school tomorrow and seeing all these high scores raising the bar for round 2.

[Velocity]

4.9/5 ... Just when i thought it was too easy. Its never perfect!!!!!!!! How do i know if i qualify for round 2

[102897108]

Velocity @ Tue Feb 28, 2012 9:14 pm wrote:

4.9/5 ... Just when i thought it was too easy. Its never perfect!!!!!!!! How do i know if i qualify for round 2

Haha I'm really curious where did you lose that 0.1 mark?

[DanielKang]

Snario @ Tue Feb 28, 2012 9:49 pm wrote:

DanielKang @ Tue Feb 28, 2012 7:11 pm wrote:

Hello, I did the junior one, and the same problem appeared as J5.
Thankfully, after rocking my head trying to figure out how to do it, I was able to successfully analyze each case then use println.
Notice that for S4, n<8, while in J5, n<5, which made manual work possible (33 cases).

Can I get full marks with this approach? Where I just do the calculations by hand and just print the results out for each case?
If I do, then I have high chance of getting 75/75 which would be awesome considering this is my very first compsci competition.

Same here.

Was it just factorial business? I didn't see a pattern

A pattern was obvious, i will say it later

[ultimatebuster]

Just confirmed that my solution for S4 takes about 1 min to run for n=8

n=7 around 2 seconds..

Damn python. lol

[saltpro15]

When will the senior problems be released? I'm undergrad this year but I'd still like to take a shot at some of them. I'm assuming from the posts here that the difficulty was lowered a bit from previous years?

[danc]

I got 60... so maybe not good enough to advance. I just didn't get an at all working solution for 4... though I know how to do it algorithmically. It's just difficult to represent. I was a little sad that recursion would run in time for S5. And with the difficulty in general.