[Unofficial] 15 puzzle - 4.672 average of 12, 4.319 average of 5 (ben1996123)

[qqwref]

he is insane

 

[Owen]

Wasn't he banned to keep these videos off the forum?

 

[Lchu613]

He got banned?

 

[qqwref]

Wasn't he banned to keep these videos off the forum?

Why would they ban someone for making speed puzzling videos? Actually, I'm pretty sure the ban was totally unrelated to sliding puzzles.

 

[Tim Major]

Plot twist: qqwref was ben all along.

I mean, has anyone ever seen both of them in the same room together?

 

[78BFE]

Why would they ban someone for making speed puzzling videos? Actually, I'm pretty sure the ban was totally unrelated to sliding puzzles.

Yeah, I think it was due to him being annoying or something along the lines of that and being irrelevant.

 

[Stefan]

Which simulator is that?

 

[MatejMuzatko]

Which simulator is that?

http://www.speedsolving.com/forum/showthread.php?44159-Multiplayer-15-puzzle-sim This one, I believe

 

[sellingseals]

I didn't even know people speed solved the 15 puzzle. He's great at it.

 

[Stefan]

http://www.speedsolving.com/forum/showthread.php?44159-Multiplayer-15-puzzle-sim This one, I believe

Yes, looks like it, thanks. Boo... just an exe, so I can't see the source code and check out the scrambling algorithm.

 

[TDM]

I still have a 0 second single. Unless ben also gets a 0 move scramble I can say I am better at him at something.

 

[Stefan]

0 move scramble

That's so unlikely that I now really suspect that the scrambling algorithm is flawed (and in that case, none of the records using it should count). Unless it wasn't called at all because of some bug outside.

 

[qqwref]

Stefan: according to Ben, his scrambling algorithm does a large number of random 3-cycles (~3-4 times the number of pieces).

I still have a 0 second single. Unless ben also gets a 0 move scramble I can say I am better at him at something.

On 15 puzzle? I very much doubt that that happened with a proper scrambling algorithm (the probability of a solved scramble is about one in 10^13). It is almost guaranteed that you found a bug, or that the program you were using just had a bad scrambler. Something like "do X random moves" may look decent most of the time but will occasionally generate very poor scrambles.

EDIT: If it was on Ben's sim, it must have been on an old version (the new ones don't allow solved scrambles, since like v12.3) and also involved some other bug (making the program think you were doing a solve when you weren't).

 

[Owen]

I remember vcuber's scambling algorithm was flawed. Mr. Toad's and Ben's seem about equivalent. Not sure if either is random-state.

 

[kinch2002]

Why aren't all the programs using random state? It sounds like it should be easy. I wrote a sim in Excel (vba) which was random state scrambling, although I didn't investigate how to identity parity so it's not quite complete.

Generate Random state.
Check for parity.
If parity then generate again. Etc.

 

[irontwig]

Generate Random state.
Check for parity.
If parity then generate again. Etc.

Why not just random state the first 13 (for the 15 puzzle)? The last two would surely be forced, right?

 

[kinch2002]

Why not just random state the first 13 (for the 15 puzzle)? The last two would surely be forced, right?

Yes you could. It would be a little more complicated given you have to keep track of the space, but yes it can work like that

 

[rj]

I still have a 0 second single. Unless ben also gets a 0 move scramble I can say I am better at him at something.

But I still hold the 3 puzzle UWR!

 

[cmhardw]

Wow, that really is impressive!

 

[Jakube]

Yes you could. It would be a little more complicated given you have to keep track of the space, but yes it can work like that

It's not that difficult. Something simple like this should return a solveable random-state scramble. Just keep track on how many switches (2-cycles) you made.

A={1,2,3,...,15}
switchCnt = 0
for (i = 0, i < 13, i++){
   j = random(i, 14)
   switch(A[i],A[j])
   if (i != j)
      switchCnt++
}
if (switchCnt%2 == 1)
   switch(A[13],A[14])
return A