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Apr 2007

I am not sure also to understand well the question:
do we have to find the MAXIMUM number of consecutive numbers for which the sum of its digits is not divisible by 13?

Please help me

I am not sure also to understand well the question:
do we have to find the MAXIMUM number of consecutive numbers for which the sum of its digits is not divisible by 13?

Please help me

Yes, you must find maximum.

I try to open the file answer.txt but it is locked by a password.
I am not sure that I understand how to find this password?
Does it depend on the Problem 1?

Help

I will say only this: the password for Problem 2 does not depend on Problem 1.

I believe there is no need to discover the password, but rather, we should use the knowledge brought to us by the encrypted file, that is, the algorithm CRC32, the length of the message and the size of the file... I just don't know how to relate all that.

In the same way, I don't know what to do in the images problems, I mean, What are they asking? What are we looking for there?

This is the first time I've seen problems like these (except the Project Euler ones) and the part where you discover what they actually want you to do with those images is the most fun part smile

that might be true, but fun quickly become frustration, being as it is that there are virtually no clues as to what to do... especially in the problem 10.

Hello,

I also don´t know what to do with problem 10, but I can tell you that problem 3 is an autostereogram, and can be solved using a tecnique called 'Magic Eye'.

i dont find zooming in and out a computer image healthy
and for the problem 10s picture
look to the picture properties
there are:
Number 758932
and
spoj.pl/content/turbo:032948.gif4
but i couldnt solve it, are they solveable in current contest?

also a note to the admin, i think answer.zip s password should be updated

You don't have to do that. If you can can handle the normal print variations without having to zoom in/out, you can do the same if it's on a computer screen. In any case, you can easily turn the brightness down if the screen hurts to look at (although this is only really a problem with CRTs.)

It's also possible to obtain the answer using Graphic editing software (although this basic method won't work on more complex versions of that image.)

Please help me!
Does it depend on another problem in the PCV2?
I am very frustated to don't understand the trick...

It doesn't depend on the answer to any other problem. You can either try to guess the password or use brute force.

like i said before the password should be changed, it should be FUN

don't worry about problem 10, it's perfectly solvable in this contest.

hello,

I'm getting a little desperate with this one. I found a pattern:

  v( 1 ) = v( 2^0 ) = 2
  v( 2 ) = v( 2^1 ) = 3
  v( 4 ) = v( 2^2 ) = 4
  v( 8 ) = v( 2^3 ) = 5
  v( 16 ) = v( 2^4 ) = 6
  v( 32 ) = v( 2^5 ) = 7

Therefor it seems that v(2^x) = x+2, but when i submit 1002 for v(2^1000) I'm getting wrong answer. żAm I taking a wrong aproach or could it be that '^' in this case stands for bitwise operator XOR and we have to find v(1002)?

Thanks...

Try working out a few more terms in that sequence, and you'll notice the pattern doesn't continue wink

What's the method of determining the password for problem 2? I've tried a variety of tactics (e.g. guessing "password", using the filename as password, file size, and so on), but none of these had any result.

I can eventually figure out the other problems in PCV2, but bruteforcing the password didn't help me.