8 queens chess problem

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N.Beltov N.Beltov's picture
8 queens chess problem

There's been a posting about the 8 Queens problem. That is, place 8 Queens on a chessboard in such a way that they don't cover each other.

There are many solutions to that problem. However, if you ADD one pawn, there is a solution with 9 Queens. Have a look ...

 

Unionist

Big deal. If I add two more pawns, there's a solution with 10 queens. Mind you, I'm eyeballing it, so I may be wrong. See if you can find my solution.

N.Beltov N.Beltov's picture

Well, U, you could ignore this thread if you felt it was not worthy of your attention.

This is, basically, an orthodox chess problem. I realize that there are no Kings on the Board, but their addition would make solving the problems easier and not more difficult.

It IS possible to have 9 Queens of one colour in an orthodox chess game. 10 is impossible. Now go play in traffic. :)

Caissa

Spoiler alert: The solutions as explained on Wiki

http://en.wikipedia.org/wiki/Eight_queens_puzzle

Unionist

N.Beltov wrote:

It IS possible to have 9 Queens of one colour in an orthodox chess game. 10 is impossible. Now go play in traffic. :)

In other words, you can't solve my 10-queen problem? Ok, just say so, no need to get sniffy.

Are you sure you're not related to Bogoljubov?

ETA: Ha!! Even Caissa's Wikipedia cheat link doesn't contain a solution to my amended puzzle:

Quote:
Further generalization of the problem (complete solution is currently unknown): given an n×n chess board and m > n queens, find the minimum number of pawns, so that the m queens and the pawns can be set up on the board in such a way that no two queens attack each other.

Anyway, let me know when you're ready to say "parent's sibling", and I'll give you my 10-queen solution.

Ripple

Quote:
"parent's sibling"

 

heh.

Unionist

Good stuff, Caissa (especially after the 90 degree rotation) - thanks for competing!

My initial solution was pawns on a5 and b4, with a queen on b4 - although, as N.Beltov correctly points out, ten queens aren't possible (nor are positions without kings).

Caissa

If we use the top puzzle you put a pawn on d8 and a pawn  on e7 and a Q on e8. Since it's a puzzle we will ignore the fact that a pawn can't go on d8. Or we will just give the board a quarter turn. That gives us 10 queens.

Caissa

Here is an easy one. How many Knights can you put on the board without any attacking another?

Unionist

Caissa wrote:

Here is an easy one. How many Knights can you put on the board without any attacking another?

Answer: None. Knights are so aggressive, even a single one will attack anything that isn't nailed down:

http://www.youtube.com/watch?v=dhRUe-gz690

 

Caissa

Okay- anyone care to take a crack at a chess answer? I'm sure Unioinist knows it. My link above contains a spoiler.

Unionist

How many players can you treat like pawns before they capture the kings, queens, and bishops?

Sorry, Caissa and N.Beltov, I'm being disruptive. Can't help it.

Caissa

Sounds like Pre-Revolutionary France, Unionist.

Unionist

I wish.

Catchfire Catchfire's picture
Catchfire Catchfire's picture

Chess960 (a.k.a. Fischer Random Chess)

Quote:
A return to the pleasure of the first move in a vast unexplored wilderness

I've never really bothered with FRC, mostly because a lot of my strategy relies on controlling the game from the outset with carefully chosen openings not deeply studied by others at my skill level (i.e. Caro-Kann, King's Gambit and/or Stonewall Attack. Of course, if someone hits me with the Sicilian I can rely on the fact that unless you're 1800+, you don't know how to play it.)

Any babble chess wizards (ikosmos, Caissa, I am looking in your direction) play FRC?

Caissa

I have no interest in FRC.  You can avoid the Sicilian by not playing e4 although when I do meet it I play 2. f4 and let the K-side attack begin. I play  blitz everyday at lunch and have been playing 1.Nf3  almost exclusively since the start of the year.

Catchfire Catchfire's picture

But then I wouldn't be able to play the King's gambit! No point in chess without the King's gambit, I say. Actually, I used to play 2. f4, but the opening still got out of hand for my brain too soon. I like the rigorous pawn structure of the C-K and Stonewall. It makes me feel homey. The same reason I used to play the King's Indian too.

And this:

Caissa wrote:
I play  blitz everyday at lunch and have been playing 1.Nf3  almost exclusively since the start of the year.

is why I will never play you, Caissa (not, of course, because you'll likely eviscerate me).

Caissa

I try to avoid the King's Gambit as black. I play either the French or the Caro-Kann almost religiously unless I know that white likes the Ruy Lopez and I can uncork the Schliemann's. Against 1.d4 I try to stir things towards the Benko Gambit or occassionally I'll play the Budapest Gambit.

ventureforth

Caissa wrote:

I try to avoid the King's Gambit as black. I play either the French or the Caro-Kann almost religiously unless I know that white likes the Ruy Lopez and I can uncork the Schliemann's. Against 1.d4 I try to stir things towards the Benko Gambit or occassionally I'll play the Budapest Gambit.

Most Ruy players are now prepared for the Schliemann so not such a surprise.

Caissa

True enough but in blitz it can often have a surprise value.

Catchfire Catchfire's picture

European Chess Union implements dress code for women participants

Quote:
We came up with that idea because we noticed that during the games many of the players were not wearing proper clothes. There is dress code in many different sports, and we decided to establish our rules as well. This is the first European tournament where we are applying those regulations. I was here during three rounds and I've got an impression that we have to work much more on those regulations.

Players respond:

Quote:
Almira Skripchenko: I don’t think it’s very suitable to include dress-code rules in women tournaments. I think everyone is trying to do their best, and women should not be told what to wear. I don’t think it should be a rule and I don’t think anyone should be forced to follow it. Why does everyone want to punish us? I also mean the “zero tolerance” rule. It’s already a hard enough job playing chess (laughing). I believe that chess players should behave like normal human beings, and thus there is no need to make any special regulations for players. I think it’s really normal for every chess player to respect the efforts of the organizers and sponsors and try to look as decent as possible. Everyone should try to do their best. I think the organizers of private events can write down in the contracts whatever they want, even a dress-code rule. But we should not forget that most players paid by themselves to come here and play.

Caissa

Of course, as the goddess of chess I have some thoughts on this issue.

First, I would never tell a woman how to dress.

A few years ago FIDE (Federation Internationale des echecs) attempted to bring in uniforms for chessplayers. They were plum ugly and looked like something out of a bad science fiction movie.

Most chessplayers are male. As a group of individuals they tend to be slovenly dressed to put it politely.

 At the upper echelons of chess, male players tend to wear suits and ties. I have never really observed the dress of the top women players. The best female chess player in the world usually wears a suit from tournament pictures I have seen.

There has been much ribald discussion of the new regulations amongst chess players online. I can't repeat any of it here on Babble.

 

Catchfire Catchfire's picture

Rooked: the evolution of cheating in chess

It happened this spring, in the 2012 Virginia Scholastic and Collegiate Chess Tournament. Both Quentin Moore and his opponent, a rising star on the D.C.-area chess scene named Clark Smiley, came into their match undefeated over the weekend-long competition. So the state title and an expenses-paid cross-country trip to the national high school championships would likely go to the game's winner.

Judging by his pre-tournament rating — 2141, according to the U.S. Chess Federation system, making him the second-highest of the 75 players vying for the high school title — Moore shouldn't have had any trouble getting past Smiley (1875). But Smiley was on fire, having won nine of the 12 previous rated tournaments in which he'd played and taken second place in the other three. Smiley's former high school coach, forgetting that the kid's spree came in state and regional events and not globally significant competitions, now says Smiley had put up "a record only Bobby Fischer could have."

And in a match played in an earlier round at the Scholastic tournament, held at a Best Western in McLean, Virginia, Smiley had whupped Aravind Ponukumati, a teammate of Moore's on the perennial state champion chess squad from Thomas Jefferson High School for Science and Technology. Smiley was rated almost 200 points below his opponent, but played "several hundred points above his rating," Ponukumati says.

"He was playing so aggressive," Ponukumati said. "I remember thinking, He's crushing me!"

ikosmos ikosmos's picture

I'm not that fond of extremely fast chess (bullet chess, e.g., at 1 minute a side) but it is a great way to determine whether your opponent is cheating. It even works with online chess because no one can really type the moves that quickly and wait for the engine to generate a reply before making a move. Having said that, I don't doubt that there is plenty of online cheating with slower time controls. 

In Canadian chess events, the hand-held device most used is Monroi.  For example, they were used in the Canadian Open in Victoria BC last July. At that event, the only real debate was whether the Monroi was superior to another device which records the game using a special board with pressure "pads" or something like that. There were no cheating worries.

This issue of cheating rose to the level of farce with the World Ch match between Bulgarian Veselin Topalov and Russian Vladimir Kramnik. "Bathroom gate" or something like that it was called. Idiotic. I think it was mostly the doing of Topalov's "Second". It revolved around the "excessive" use of the bathroom by Kramnik who, it turns out, had/has a medical condition that took him to the bathroom more frequently than usual.

 

Catchfire Catchfire's picture

Kramnik is the best ever. He can use the bathroom as much as he wishes, as far as I am concerned.

ikosmos ikosmos's picture

OK, but Vishy beat him and has held the title ever since. 

Then there's some young pup from Norway who doesn't even participate in the W CH cycle, citing unfairness, etc.

An American who plays a great deal in Canada is also worth watching: Hikaru Nakamura takes part in all sorts of Canadian chess events, simuls, even weekend Swisses if you please, etc.

Caissa

I think after the Chess Olympiad Nakamura might be ranked third in the world. Anand, as is his want, once agin avoided the Olympiad.

Carlsen will eat Kramnik for breakfast if they ever have a match.