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A Christmas Chess Puzzle
Frederic Friedel writes "Here's a nice little chess puzzle I got from Grandmaster John Nunn many years ago. It looks incredibly simple, but even the strongest players in world have been stumped by it. The problem can be stated in one simple line:
A game begins with 1.e4 and ends in the fifth move with knight takes rook mate. What are the moves?
If you want to read a couple of stories on it, go to Chessbase. There is a very special prize to be won if you are able to solve it -- a book signed by some of the world's top chess players, testifying that the winner is The Greatest.
"
2. a4 b4
3. a1-a3 c2
4. a3-d3 b4
5. g7-e2 d3++
-->
Update: 12/25 11:50 by michael : Well, I thought I figured it out, but I was wrong.
1. e4 b8-c62. a4 b4
3. a1-a3 c2
4. a3-d3 b4
5. g7-e2 d3++
-->
Just to clear up some confusion below, the condition is simply that a knight makes the last move of the game, which is a capture of a rook on move five (either color), and this results in checkmate for the other king. Either the knight or some other piece could be giving the check. One poster below reasons that black would be the one giving the checkmate - this is very sound reasoning. :) You just have to think outside the box.
Reminds me of when Chessmaster 6500 beat me in 5 moves when it was set on level novice.
I'm a REALLY bad chess player.
http://www.chessbase.com/puzzle/puzzle.h tm
Gates' Law: Every 18 months, the speed of software halves.
Is there a simple engine that I can download? All you'd need to do is brute-force the possibilities. I might be very wrong, but 5 moves doesn't sound like it would take very long for a fast computer. Just grep through the results for the end move you want.
Gates' Law: Every 18 months, the speed of software halves.
I was under the impression that slashdot was for technology news and such... I don't know if this even really qualifies as "News for Nerds".
I'd appreciate it if this wasn't moderated down, but I know it will be. Oh well. At least don't do it for "Troll", cuz I'm not trolling. (Subliminal message to moderators: You know you want to...)
Restating the obvious since nineteen aught five.
Doesn't say if the 5th move is going to be mated by black or white.... guess it'll be easier if it's black mate in 5
do not in anyway underestimate anybody, especially yourself
Then what makes you think anyone here will do any better?
Damn damn damn. I can do it in *SIX* moves. I try again. :) I'd help if it said who wins. My bets on Black. :)
No, we have a thing called "time zones". You obviously didn't notice. :)
Yes, I know, chess is the "game of kings" and all... but I've recently learned Go, and no one else seems to play it. Does anyone else on Slashdot play this game?
To the editors: your English is as bad as your Perl. Please go back to grade school.
1.e4 f5 2.f4 g5 3.Qh5X
Knight --> fridge --> bourbon --> mate. It can be done in 4.
I assume we are talking about Scholar's Mate, which is very similar to Fool's Mate. The two are described on this page in some detail.
The answer, from that page, is "1.e4 e5 2.Bc4 Bc5 3.Qh5 Nf6 4.Qxf7#"
indeed. touche.
Of course, its quite amusing that "isn't this supposed to be a tech news site" gets hit by a moderator before my BLATENT first post.
idiot moderator? or are "slashdot/linux isn't as informative/elite/cool/fun/etc as it used ot be" posts are more annoying than "f1RsT p0St!!111!"?
1. e2-e4 | b7-b6
2. f1-a6 | c8xa6
3. g1-f3 | g8-f6
4. g2-g3 | f6-d5
5. h1-g1 | d5-e3
6. g1-g2 | e3xg2++
It's whittling it down to just 5 that's tough.
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
that means ther can only be FOUR more moves after the 1.e4. looks impossible
I've played Go some. When I was going to school at Berkeley, and when there was a lunchtime Go club at a place I worked. Generally though, it's hard to find people to play Go in the US, I agree.
:) It's also much, much harder to brute force.
It's a more forgiving game for people like me who get things right the second time -- usually.
what is rook mate and how does a knight take rook mate?
Let's say a chess game has on average 60 moves by each player, who on average chooses from 10 possibilities. That's 10^120 possible games. Let's say you have a petahertz computer that can evalutate a move per clock. 10^15 moves per second. Let's say every proton in the universe was such a computer and they all worked in parallel. That's 10^80 computers, according to physicist's estimates. Solution time is 10^120 / (10^80 * 10^15) = 10^35 seconds. Since a year only has pi * 10^7 seconds, it would take way over 10^27 years to solve, or about 10^17 times the lifetime of the universe. Chess WILL NEVER be solved by brute force.
Come on out of the closet...you know you'd like it if some sailors tied you up and took you for a ride. It's okay man it was obvious from your first word....
AGAINST STOOPIDITY!
I once played a chess game that, when you lost, the computer laughed at you...
And if you won, the board suddenly turned around, so you lost... and the computer laughed...
At least, I'm -pretty- sure this happened.
The more I think about it, the less it seems it really happened.
Devilled Eggs - A disturbing little creation of mine.
1. e2-e4 | g7-g6
2. g1-e2 | g8-f6
3. e2-f4 | h8-g8
4. f4-h5 | g8-g7
5. h5xg7+++
(mate)
did anybody else get peyote for Christmas?
This riddle CAN be solved by a computer:
There once was a girl from Peru,
who filled her panties with glue.
She said with a grin,
they paid to get in,
and they'll pay to get out again, too!
Oh, wait, that's a limerick.
No comment at this time
Come on you know you are dying to find out what it's like. Come on little boy. Get out of the closet and join the dark side..
I'm pretty disappointed that ChessBase couldn't make up their own puzzle at least... ;-) )
;-)
I'm almost positive I have this puzzle in a book in my house. (but then again, I have a *lot* of chess books
Oh well...
For those interested, Hugh Courtney's annual Christmas Puzzles in the british magazine "Chess" are especially enteraining
Here, assuming you only speak English.
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
the knight can take the rook last, but the queen can make the checkmate? if you read the page, at the bottom, the guy who didn't figure it out argued that it wasnt stated properly. ..."When I told him the solution on the phone I could hear Mikhail Botvinnik gasp in the background. And Garry, who was convinced I had stated the problem incorrectly, couldn't believe that he and his students had missed it."...
the knight can take the rook last, but the queen can make the checkmate? like the knight takes the rook and moves out of the way for a queen to make the checkmate. get what im saying?
..."When I told him the solution on the phone I could hear Mikhail Botvinnik gasp in the background. And Garry, who was convinced I had stated the problem incorrectly, couldn't believe that he and his students had missed it."...
if you read the page, at the bottom, the guy who didn't figure it out argued that it wasnt stated properly.
Apologies for my lack of knowledge of chess notation...
h7 - h6 (black king's rook's pawn)
g1 - f3 (white king's knight)
g7 - g6 (black king's knight's pawn)
f3 - e5 (white king's knight)
f7 - f6 (black king's bishop's pawn)
e5 - g6 (white king's knight)
a7 - a6 (black queen's rook's pawn - irrelevant)
d1 - h5 (white queen)
a6 - a5 (black queen's rook's pawn - irrelevant)
g6 - h8 (white king's knight takes rook)
I think that satisfies all of the requirements.
I/O Error G-17: Aborting Installation
A chess solution may be possible if you consider that most algorithms aimed at this problem are only going to consider reasonable moves and plausible board positions. Kind of like "guided" brute force.
Checkers on the other hand, - I've read somewhere that there are over 10^120 plausible board positions: orders of magnitude greater than the estimated number of particles in the universe ; )
-q
The spoiler that's been posted is not a solution? I won't repeat it here, just in case, but as far as I can see, black checks white at one point, and white never moves out of check. If this is 'thinking outside the box' and this is the actual solution, this puzzle is useless. :) Breaking the rules to solve the puzzle is, in my opinion, cheating. Did I miss something?!
Mate is given on whites 6th move, so this isn't a valid solution. Close though. :)
I must be missing something... maybe the pieces are wrong... I dont understand the letter-number thing... Move the right knight 2 forward and 1 left; 2 right and 1 forward; 2 forward and 1 left; 2 forward and 1 left. Gee that was really easy... could someone tell me how the board is lettered-numbered?
Anonymous Hay goes in and I come out...
From left to right, when sitting on Whites side of the table, is A-H. From the white side to the black side, is 1-8.
:)
So D1 is Whites Queen.
When stating a move, the result is sometimes stated by itself, when its obvious what happened.
(eg: e4, theres only one piece that can make that move, the pawn at e2).
For more info, check out your local chess faq
I use to have a funny sig, but slash cut it off, and I forgot what the punchline was.
How about:
1 E2-E4 D7-D6
2 D1-E2 C8-G4
3 E2-E3 B8-C6
4 A2-A3 C6-D4
5 A3-A4 D4-C2++
Any problems with this one? The above spoiler does not work as white fails to move out of check at one point.
Shawn Asmussen
what about pawn c2-d3???? what the heck? that's not mate...that was just a dumb check..am i missing something?
1. e4 b8-c6
:)
2. a2-a4 c6-b4
3. a1-a3 b4-c2
4. a1-d4 c2-b4
5. g1-e2 b4-d3++
However, in my opinion white would need to a terrible player.
Alot of people have been saying that it might be a trick(discovered check), here is a way to do it in 6.
Be aware that this solution only involes white working hard, and that black is just wasting away moves after the first. If you can maybe use those wasted moves, it might lower the move count down by one.
1. e2-24, g7-g5
2. d1-h5, g5-g4
3. g1-f3, g4-g3
4. f3-g5, g3xh2
5. g5-f7, a7-a6
6. f7xh8
If you feel like it, this might be in 5 moves(ignoring the first)....
knight takes rook mate. if you smash the rook, the king still lives!! so, not a real solution.
What if WHITE Knight takes BLACK Rook, and this causes mate for WHITE? Surely its not that. But it is said: And Garry, who was convinced I had stated the problem incorrectly, couldn't believe that he and his students had missed it.
If its some silly little trick in the wording, I'm going to be anoyed. Very much so. Grr. Of course, in the meantime, I'm not getting anywhere with this thing. 101 ways to mate in 6, but none in 5. Sigh.
I'm thinking maybe you need to promote a Pawn? Just a though. Anyone else out there actually working on this?
I doubt it. Very much.
If I'm not mistaken you're not allowed to commit suicide. That is you cannot move so that w/o the oppnent making a move you put your king in harm's way.
1. White 2. Black 3. White 4. Black 5. White
Now unless 2 + 2 = 5, (hint hint: the chess game at the end of 1984), there's no way black wins.
The message on the other side of this sig is false.
Go read IBM or HP's internal memos if that's what you want.
And frankly I think it shouldn't be moderated down only so that we get more discussion about how disturbingly narrow minded your comment is.
The message on the other side of this sig is false.
I think you mean: 1. e4 Nc6 2. a4 Nb4 3. Ra3 Nxc2 4. Rd3 Nb4 5. Ne2 Nxd3# Eh?
your 3rd move. you cannot go from a3-d3 because you are ignoring the check that the knight has on the king.
Heh, actually, I've since changed my mind. I just thought it might be black, cuz white is too obvious...
whats this 'nice little prize' that guy is tlaking about? for all we know it could be something crappy. im sure someone here can git it right, you just have to think about it. maybe try working backwards or something. but im not gonna try because this confuses me. good luck y'all
read closer
If anyone is a chess person could you make a quick variation of this puzzle that can be played on Zillions (http://www.zillions-of-games.com) please. I don't follow chess lingo but would be interested in playing. Coding games in Zillions is really easy so it should be simple. BTW anybody who likes board games be sure to try to convince them to port Zillions to Linux. They aen't unwilling but need some motivation. :)
At what price learning? At what cost wisdom? The price is a man's peace of mind, and the cost is his life.
maybe the king/rook castles and the knight takes that rook, while moving out of the way for a queen?
Actually, chess moves work like this: 1. white, black 2. white, black .. .. 5. white (mate) or 5. white, black (mate)
2. The mate is to the king side (the side with no queen- think of the way a knight would have to move...)
3. It's not a discover mate. That's because b1/b8 to a1/a8 takes at least four moves- which doesn't leave enough time for a relevant queen or bishop move by either side (black must move a pawn.)
4. The mate does not involve moving any rooks. There are only four positions from which a knight can mate a king on e1/e8; there isn't enough time to move a rook somewhere relevant and make sure it's not protected by any other pieces.
5. The mate is apparently by black. I say this because, if it's by white, black only has four moves- but a black mate gives black five moves, which should be the least amount you need (assuming e2-e4 is irrelevant- it's a red herring.)
That's what I was able to figure out...good luck
Remember: All bugs are shallow to many eyes. Same thing goes for Chess problems. :)
Here, I got an idea. Anyone who wants to discuss the problem, I'll start a room called #chess on slashnet.org. come one come all. :)
I have discovered a truly marvellous solution to this problem, which however this textbox is not large enough to contain.
(Now if somebody else actually publishes the solution it will at least be named after me.)
"He who takes credit for everything, is bound to get credit for something."
-My Dad
One of the players has to pee like a racehorse and concedes the game. Just a guess, however. I could be wrong.
Except that's not how moves are counted in chess. A "move" in chess counts both white and black, so a mate in the fifth move could end with either white or black moving:
1. White Black 2. White Black 3. White Black 4. White Black 5. White
or
1. White Black 2. White Black 3. White Black 4. White Black 5. White Black
The king is on e1, so there's no way in heck he can get over to g1. As for e2, that's covered by the bishop on a6. He is truly checkmated, for all the good it does in this contest.
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
E2 - E4 (the starting move required by white)
D7 - D6 (black queen's pawn)
F2 - F4 (white king's pawn)
G8 - F6 (black king's knight)
E1 - F2 (white king)
F6 - G4 (black king's knight - check)
F2 - G3 (white king)
G4 - F2 (black king's knight)
G1 - F3 (white king's knight)
F2 - H1 (black king's knight takes white king's rook - checkmate)
I/O Error G-17: Aborting Installation
That's a variation of fools mate:
:)
1. f4 e6
2. g4 qh4++
but alas, it doesn't involve a night or rook
-=-=-=-=-
-=-=-=-=-
My mom's going to kick you in the face!
This is going to be a little bit OT, but this needs to be said anyway
Do you know that both the game of Chess and GO originated from the East - from China?
The Chess game was introduced to the Western world (Europe and Middle East) by the Mongolian invaders, whose has learned the game of Chess from the Chinese.
The GO game was introduced to the Western world via the Japanese, whom in turn learned it from the Chinese.
Sorry for this not-so-on-topic message, but I think you might want to learn something this Christmas day anyway.
Merry Christmas !!
Muchas Gracias, Señor Edward Snowden !
anyone who wants to chat about this or wants to share ideas, come to:
#chess
slashnet.org
dont count on it
This message is going to be a little bit Off-Topic, please do not get too offended
Do you know that both the games of Chess and GO originated from the East - from China?
The Chess game was introduced to the Western world (Europe and Middle East) by the Mongolian invaders, whose has learned the game of Chess from the Chinese.
The GO game was introduced to the Western world via the Japanese, whom in turn learned it from the Chinese.
Sorry for this not-so-on-topic message, but I think you might want to learn something this Christmas day anyway.
Merry Christmas !!
Muchas Gracias, Señor Edward Snowden !
Another thing to note is the knight cannot take the rook in under 3 moves. This only leaves 2 moves to play with.
Castling takes 4 moves minimum. That only leaves 1 move to move the rook into a position that the other knight can then take it, and put the king into mate (discover or otherwise).
This leads me to conclude that castling isn't an option.
At first (and 2nd, 3rd, 4th... nth) glance, it seems impossible. There just aren't enough moves. And anyone who has tried this has come to the conclusion, "I can do it in six".
Grand Masters have been stumped. So this means one of two things.
it ISN'T classical. And its the sort of move which never happens in chess.
and/or Theres a trick in the interpretation of the instructions.
One question I have, is a matter of wording. and ends in the fifth move with knight takes rook mate. Is it possible that the knight it white, and the mate is done by black?
Technically, it'd still be move 5. And in move a knight could attack a rook.
Only problem with this is, it takes a knight 4 moves to attack a rook (assuming the rook doesn't move, since I'd assume the other player would be moving ass to get into a mate possition).
I use to have a funny sig, but slash cut it off, and I forgot what the punchline was.
How is the notation "wack"? It seems kind of normal to me...
1. Does it involve MS? If so, 75% of the people will hate the MS led answer, regardless of how it came about. .005% to the 5 first posters. .995 will have discussions on topic, but their message threads will be spaced apart by the rest of the banter.
2. FreeBSD vs Linux? 10% will get so caught up on what OS Netscape/Lynx/Opera was running on to post the ideas to each other, they will never get anywhere. The MS people are exluded above. Mac users, who uses a mac? (running away)
3.
4. 14% will somehow discuss moderation or how checkers and go have similar problems. Thus starting new threads.
5. The rest
There was hope..
---
-
ping -f 255.255.255.255 # if only
Can't be done, for one reason: you can't put yourself in check.
:)
Nice try, though.
Bleah. This thing took three hours of my life in which I could have been doing something productive, like playing Everquest...time to let someone else have a go.
Merry Christmas to all, and to all a good night
If this is readable as "Knight takes rook," "Mate," then:
1. e4 Nc6
2. Qf3 Na5
3. e5 Nb3
4. e6 Nxa1
5. exf7#
There were mentions that there might be a bit of word-play going on here.. I wonder if it comes down to that?
It says 'ends in the fifth move with...'
The way I interpret that, it means that knight taking rook is the last move, since the game ends 'with that move'.
You could be talking about the knight moving from a position that was blocking a check(mate), but that wouldn't be a legal move.
Try this
1. e2-e4 | g8-f6
2. g1-f3 | f6-e4
3. f3-g5 | e7-e6
4. g5-f7 | d8-h4
5. f7-h8 | h4-f2+++
This ends in "knight takes rook, mate"
...where there are 2 articles: "Science: 50 Year Old Quantum Physics Problem Solved" and "A Christmas Chess Puzzle" next to each other and having tried this problem myself, leads me to daydream this:
Slashdot, 50 years from now...
Slashdot: 50 Year Old Chess Puzzle solved
Finaly 50 years after the chess puzzle was posted, an Anonymous Coward has posted a correct and working solution to the elusive chess puzzle.
This puzzle was first introduced 50 years ago at Christmas time, as something for the readers to chew on. CmdrTaco, Hermos, and thousands of other slashdot readers have not been to sleep since.
The article was upto its 10 millionth comment when Hermos finally archieved it on its dedicated 50terabyte drive.
I use to have a funny sig, but slash cut it off, and I forgot what the punchline was.
The brief version (for those who don't care to click on the link the previous AC provided):
Go is a game played worldwide, but has the strongest "community" in the Orient, where there are Go professionals and professional Go commentators and writers (especially in Japan). The rules are fairly simple but unfortunately not simple enough to reproduce here (especially since I'm doing this from memory). Very briefly, it's played on the intersections of a 19x19 grid of lines with pieces called stones. Players alternate placing stones on the grid, attempting to capture as much territory as possible by making it impossible for the opposing player to place uncapturable stones inside the territory. A stone or group of stones is captured if it is completely surrounded by enemy stones, so if a group can't be surrounded it can't be captured. Captured stones count against a player at the end of the game, so efficiency is paramount, both in securing territory and in trying to attack it.
I remember reading a summary of a book written over 25 years ago comparing chess and go in the context of Eastern vs. Western military philosophy (this was toward the end of the Vietnam war). The author's thesis was that in chess, the object is to capture a particular piece, and a player can sacrifice as many of his pieces as necessary to capture the king. In go, the goal is not to capture particular pieces (in fact, every go stone is just as powerful as every other -- it's how groups of stones are deployed that make them weak or powerful), but to capture territory, and as I mentioned above, the more efficient you are at it, the better go player you'll be,
--
Someone you trust is one of us.
Just look up (or down depending on the moderation) and see that the comments are of a supreme quality, and the discussions are very intellectual. Not too much name-calling or bashing here.
How many people like the idea of having more chess stories on slashdot? Let's just maybe get an informal poll here. Maybe we could have chess (or otherwise) puzzles linked to more often. Solving puzzles is certainly a trait shared by many nerds.
Let's make it a habit. Who's with me?
There's no reason for a sig here.
Forget cracking encryption keys, why don't we use the power of distributed computing to solve chess puzzles?
These figures from a chess-computer programmer:
There are 4,865,609 different 5ply chess games
There are 119,060,324 different 6ply (3 moves) chess games
Now, continue on this scale of increasing..
calculating all 10ply positions would take a long time.
Now, for my real point. Doing it by brute force misses the point. The enjoyment of chess problems is the effort and lateral thinking expended in solving them. I don't want to see a solution - I want to work it out for myself. (Big bad nasties to those who have posted lines on slashdot - I've tried to not read them).
For chess aficionadoes, here is a related problem by Sam Lloyd (which a computer would solve quickly, incidentally, but which I enjoyed finding):
1. f3 ???
2. Kf2 ???
3. Kg3 ???
4. Kh4 ??? mate
Fill in the four missing black moves
Nunn seems to be the chess world's Puzzlin' Grand-pappy. Given his status, the "puzzle" here almost certainly lies on the chess board, not in the wording - if so, it wouldn't be at all pleasing to solve from a chess standpoint, which is the whole point of these things.
;-)
Though I admire your lateral thinking, I'm afraid this isn't "it". Or I'm wrong.
Checkers on the other hand, - I've read somewhere that there are over 10^120 plausible board positions: orders of magnitude greater than the estimated number of particles in the universe ; )
Huh? Checkers has far fewer board positions--There are only 32 usable squares and 12 identical pieces per side, as opposed to the 64 squares of chess with 16 pieces per side with many different functions. Someone computed that there are ~5e20, or ~2^69 legal checkers positions, however many of those are unobtainable by legal play. This is a vast number even for a computer, however it is certainly possible that checkers will be solved in the near future. I'm not sure if an alpha-beta search is applicable to solutions of a game, but if it is, that would cut the workload down to ~2^35 positions, which seems almost piddling...
Chess, on the other hand, has an astronomical number of positions and will never be solved by brute-forcing with conventional computers. Should quantum computation ever become a reality that may change.
Of course this problem is many many magnitudes easier than solving chess, though still not quite pocket-calculator material.
Nate
A *move* is 1> White Black . What you have said is usually termed as a ply (Ply == 1/2 move)
I can throw myself at the ground, and miss.
I think I finally got it.
1. e2-e4, g8-f6
2. f1-e2, f6-g4
3. e1-f1, g4xh2
4. d1-e1, h2-g4
5. h1-h2, g4xh2+++
Enfinity
Oops, move 4 is illegeal. Sorry.
Since I can't find my chess set, I had to dig one up on NoNAGS under their games pile (EGChess).
I couldn't find a decent java game that didn't require two different computers. (sorry)
Onthe brute force side, given that we have a limited number of moves and a limited possible number of moves in a turn, this should fall well into the brute force category. Hmmm. 9 moves maximum Black only has 20 possible moves. 8 moves after that, White has 28 possible moves. 7 moves left. At that rate it should be possible to brute force the dang thing in a reasonable period of time with enough decent resources.
But I'm going to sit here and pound my head on a virtual chessboard. I figure I'll find the answer just after everyone else.
No Zen is good zen
The solution: 1.e4 Nc6 2.a4 Nb4 3.Ra3 d6 4.Rd3 Bg4 5.c3 Nxd3++
1. e4 f5 2. Ne2 g5 3. Nf4 h5 4. Ng6 a5 5. Qxh5 a4 6. Nxh8#
...a5.
Ok, so you see that I've wasted a black move on 4.
Can that move be used to re-position the rook so that this works? I was thinking earlier that the solution had to begin with 1. e4 h5 2. Qxh5 Rxh5, with white's bishop providing the checkmate, but I just don't see how that works, even if black's rook moves to the center....
Hope this helps.
Okay, if I'm thinking "outside the box enough", I think this might satisfy the solution.
A game begins with 1.e4 and ends in the fifth move with knight takes rook mate.
That is the problem. Now, it's possible, that with a slight bit of imagination (which I have an abundance of), the sentence could be read as such: "A game begins with 1.e4, and ends in the fifth move with knight taking rook, Mate."
Just re-read the sentence in your best Aussie impression, and you've got it. Doesn't matter the sequence of moves, long as the fifth move ends in knight taking rook...
Too far outside the box??? I dunno... Never was all that great at chess...
6. Bxd3
Stupid question perhaps.. (I'm no expert on chess terminology), but does the term 'mate' necessarily refer to checkmate? Could the game end, instead, with a stalemate?
Since being able to finally sleep soundly is worth much more than confirming if I will receive a book about chess, I won't bother posting an answer that could be refuted and instead go directly to satisfied sleep.
My room. Pure geek setting
And the coder don't know that the coder is getting
The worst damn puzzle in the chess world.
One that can't even be solved by Yul Brenner.
Time files - doesn't seem an hour
Been working on this puzzle, haven't even had a shower
No hope - don't you know that when you
work on this puzzle you need more than a small clue
It's an exposed check... or a castle... or a fools mate... or... or ... I don't know!
(Slashdot:)
One night of puzzles makes a hard man humble
Checkmate in six moves but the man says five
The knight moves slowly and I don't see a castle
No matter what I do, the king survives
Solving this dang puzzle just my take my life.
(The American:)
One move is very like another
Neither gets me closer to a quick kill brother
(Slashdot:)
It's a pain, it's a challenge, it's really such a pity
That you're trying to solve it since your rank's so shi77y.
(The American:)
Whaddya mean? You shoulda seen me in high school you rotton S.O.B.s!
(Slashdot:)
Linux, Brute force, need a hack.
This is worse than a Cal-tech Stack.
(The American:)
Get real! You're talking to a slacker
It's been too long since I was a hacker.
I get my kicks from coding legos, Slashdot!
(Slashdot:)
One night of puzzles makes a hard man humble
Checkmate in six moves but the man says five
The knight moves slowly and I don't see a castle
No matter what I do, the king survives
I can't solve this puzzle. I should ask my wife.
(The American:)
Slashdot's gonna be the witness
To the ultimate test of cerebral fitness
This grips me more than would a
unfair patent or bogus lawsuit
And thank god I'm only submitting a reply, not moderating it.
I don't see you guys getting
The kind of Karma I'm contemplating
I'd let you help, I would invite you.
If I could fing a solution on Yahoo.
So you better go back to your linux machines, your hacks, your compilers.
(Slashdot:)
One lousy puzzle and you're drinking vodka
The puzzle's locked inside your brain
It's like some bizarre scene from Kafka
And even whiskey wouldn't dull the pain.
This simple puzzle has driven you insane
One night of puzzles makes a hard man humble
Checkmate in six moves but the man says five
The knight moves slowly and I don't see a castle
No matter what I do, the king survives
Solving this dang puzzle just my take my life.
Apologies to Benny Andersson and Bjorn Ulvaeus, both of ABBA fame, and renown lyricist Tim Rice
No Zen is good zen
For the queen to get involved it takes 2 extraneous moves if you're black, which you just don't have to spend if you're getting the knight over there to claim the rook.
If you're white, then you can do an uncovered mate in 6 like this, but that doesn't solve the puzzle:
(white) | (black)
1. e2-e4 | g7-g5
2. d1-h5 | a7-a6
3. g1-f3 | b7-b6
4. f3-e5 | c7-c6
5. e5xf7 | c6-c5
6. f7xh8++
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
1. e2-e4 | c7-c5
2. g1-e2 | b8-c6
3. a2-a4 | c6-b4
4. a1-a2 | d8-a5
5. d2-d4 | b4-a2
Presto ?!
0. e2-e4 | b7-b6 1. f1-a6 | c8xa6 2. g1-f3 | g8-f6 3. g2-g3 | f6-d5 4. h1-g1 | d5-e3 5. g1-g2 | e3xg2++ There, now its on the fifth move :)
Look at all the pieces on the board. For there to be a stalemate, all of one player's pieces can't move. It just can't happen after 5 moves.
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
black has to take white based on the number of moves... 5 moves, white moved first, black has to move next. Meaning that black makes moves 1,3, and 5, white makes moves 2 and 4.
I need to do my laundry
Please send $3 to:
Jon Allen
p.o. box 308142
(This is Frederic. I still don't have an account at SlashDot): "If its some silly little trick in the wording, I'm going to be anoyed. Very much so. Grr." On move five it's "knight takes rook, mate!" (= buddy). Very simple. Got a number of emails with this solution. JUST KIDDING! No, no tricks. Read my report. Garry Kasparov would have _murdered_ me, torn lumps of flesh out of my body. He almost did so anyway. Five genuine moves, all legal, like 1.e4 ?? 2.?? ?? 3.?? ?? 4.?? ?? 5.RxN mate or 5.?? RxN mate. Fill in moves for "??". Best of all enter them in a chess program (e.g. get the Fritz6 demo at the ChessBase.com download section). After the last move it will display a mate.
pick one:
6. b1-c3
6. b1-d2
6. d1-d2
6. c1-d2
6. c2-c3
6. b2-b4
Interesting, but either of the two knights, the queen bishop, the queen bishop pawn or the queen herself could block the discovered check.
(This is Frederic. Sorry, no SlashDot account yet. How long does it take?) Excellent, as Montgomery Burns would say. This thread seems to have the best analysis. There is no trick, it is genuine chess, with all moves legal. 1.e4 ?? 2.?? ?? 3.?? ?? 4.?? ?? 5.RxN mate or 5.?? RxN mate. Fill in moves for "??". I will be revealing the solution only at the end of February, since there is a really neat prize to win, which involves all the top chess players in the world signing a document to confirm that the winner is The Greatest. I'll post last year's puzzle and prize soon on www.chessbase.com/puzzles/puzzles.htm.
1. e4 | Nf6
2. f3 | Nxe4
3. Qe2 | Ng3
4. Qxe7+ | Qxe7+
5. Kf2 | NxF1#
I will be posting the solution at www.ChessBase.com (and here) at the end of January or beginning of February. Don't do anything rash. Save that for after you see the solution.
How do I get to the chess chat. I don't know what #chess, slashdot.org means. Newbee.
If yours is the solution, then it's because the English language is ambiguous when it comes to the word "with": either it means "by means of" (in which case your solution fails) or it means "accompanied by" (in which case your solution succeeds, although perhaps comment #145 is better in that the knight-takes-rook move also occurs during the 5th move).
I suspect it's not supposed to be a word-play like that, though, because there are several possible solutions that make use of that trick, and this puzzle probably only has one brilliant solution. But maybe I have too much faith in John Nunn.
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
Probably the best way to brute force a solution to this problem is to use a bi-directional search tree.
Imagine two points in a space, one is the starting state of the chess game, and one the ending state. You branch outwards from both points, where the first state branches forward through game states, and the other branches backward through game states. Whenever either of these two trees touch (i.e. they share a common node), we have found a solution.
Given that the path length between the two points cannot exceed 5 (5 moves), it would be safe to limit the height of each tree to 5, or if you're clever, ceiling(5/2) (i'm not too sure about this part, data structures people should speak up about this).
AFAIK, using this search method should not strain a high-end vector processor in the least; it might even be doable on a high-end workstation. Given that the branching factor of a chess game is completely insane, a large memory would be useful to store each tree through every iteration.
The one thing that bothers me is that people a lot smarter than me must have already tried this. And failed, since no one has posted a solution. Maybe there is no solution?
Please correct me!
And I'm not even /in/ the US... :P
To the editors: your English is as bad as your Perl. Please go back to grade school.
Black's fifth move is Nxh1#, not Nxh1#. Other than that, it seems to me to be right, and WinBoard agrees. Impressive!
What a lovely answer. Made my day. :-))
And a good example of the distributed thinking power of slashdot.
> Ever seen the math on the game of Go?
;-)
Yes. I was even going to implement a Go game.
And I quickly looked over GNU Go.
I would of thought that with only 2 pieces, GO would be easier to implement.
Uh-ah!
The strategy for GO is WAY more complex then chess. Even shrinking the board down to 9x9 or 11x11 is still difficult.
Someday (like in +2000 years) we'll have computers that will be powerfull enough to have the entire search tree in Ram. Until then, the human AI will have to do
Cheers
Correct Solution is 1. e4 | Nf6 2. f3 | Nxe4 3. Qe2 | Ng3 4. Qxe7+ | Qxe7+ 5. Kf2 | NxF1# "make my taco salads pretty, jimmy!" - ucb
I can't believe it. 24 hours after my posting it's solved. Could the poster tell us (me) how he (she) found the answer?
You won't believe how cool your posting is. You made my day. Great site.
I think, if one was to study through the methods eveyone was using you would find a lot of flawed assumptions. I know I read and thought of a lot of lines of reasonings that made sense at the time, were very well thought out, but had absolutly no proof.
What assumption killed me? The assumption that I had to move a pawn to bring the queen into play. If I has challenged that assumption I might have had more Karma, or at least, a cool book.
It's nice to have my assumptions challenged a week before I find out whay Y2K really does.
No Zen is good zen
It's a cool prize. I've linked up last year's puzzle so you can see for yourself. Check it out at http://www.chessbase.com/puzzle/puzzle.h tm
Frederic
This was posted earlier by Spicy Biscuit. I'm just writing it down in a different format for those who prefer it:
:)
1. e2-e4 g8-f6
2. f2-f3 f6-e4
3. d1-e2 e4-g3
4. e2-e7 d8-e7
5. e1-f2 g3-h1++
Very ingenious solution
æeee!
This shit was bothering me the whole day today.
click here for solution
I sent email to Frederic Friedel and he responded telling me the puzzle is *not* a word game. In other words the correct solution has the form: 1. e4 ??? 2. ??? ??? 3. ??? ??? 4. ??? ??? 5. NxR# OR 5. ??? NxR# (Depending on who wins). All moves are legal.
Looks like this was copied from an AC above. Has the same typo that the AC had, and is posted 2 hours later.
"I beat you didnt' I" ??? just a thought
The game ends in checkmate in the fifth move with a pawn promotion to a knight. Enjoy.
Beer wants to be free
I'm an absolute chess novice, but I played out these moves on a chessboard, and isn't the fifth move knight takes bishop mate, and not knight takes rook mate, as specified in the problem?
The correction to the typo also had a typo, it was Nxh1# and not Nxf1#.
Firstly, I am not the poster of the solution, but I did solve it independently last night. I'm in Indonesia on holiday. I just logged on this morning to see if I had it right. It took me about 1.5 hrs. Having a chess board might have helped :) Firstly, I reasoned it was probably black that gave mate as the problem did not state that it was white. I did spend some time searching for a white solution, but not much. I tried to block in the white king with its own pieces, but this takes too long. There were only a few ways to do this and none gave a valid mate. The move e2-e4 was not helpful for this. Castling seemed a waste of time. Took too long and the rook ended in a very inconvenient position. The main problem was to get the knight across fast enough. It was taking 3/4 moves. Then I tried to help out by bringing the rook to a more convienient place. Closer but still no luck. Then I reasoned that in such a difficult puzzle the move e2-e4 was probably important, but why? I didn't think it possible to mate with knight only so I tried bringing out another piece and trying a discovered check. But this takes two moves which was too long, but how else could it be done? I had ealier found it helpful to have the black night remove an annoyingly positioned white pawn, that lead to a "solution" that wasn't valid chess - white ignores check. Well what if white were to remove a black pawn... But now it took too long for white. If black were to take the white piece taking the pawn it would help, but it was still taking two moves to get the piece somewhere useful. What this puzzle really needed I thought were some queens whizzing about the board. At this point the e1-e8 line looked very suspicious. And armed with the idea of white removing a black pawn and the black knight removing an awkward white pawn it all fell into place. Of course it wasn't so straight forward, but that was generally how I did it. (I skip the part where I tried to figure out how long it would take to write and run a program to brute force it - a long time, and the frustating bit at the end where I forgot the solution) I'm not a good chess player. I think luck may have had something to do with it for me.
Frederic, thanks for adding this great beauty for us to puzzle over and eventually admire.
It is humbling for us humans to think that even the grandmasters did not see this solution for so long, and that computers are not that much better.
But when the AHA! insight floods the mind and the puzzle is solved, it is that great creative moment when things are all so beautiful and delicious. It must be the same with chess, with programming computers, and with all great art, like the state of being in love. It is so difficult to THINK how to do it, to solve the problem, yet when the INSIGHT comes, it is so easy and wonderful. We can't really be proud because it wasn't really anything we did to solve it, the solution just came by itself.
That is the moment when we stop thinking of chess as a combat between two people, or of programming as a combat between a machine and a person, but rather we realize that this must be the way God thinks and sometimes we get a flash of it. We should thank God we are provided that flash a few times in our life! And thanks again, Frederic, for helping us see it.
I haven't played chess in 15 years and was never more than a casual player (the computer still beats me on level 1 most of the time); but, depending on how you look at the problem, I may have a solution. I am not convinced that you have to count the starting white move in your 5 moves. The problem seems to imply you have 5 moves from the stated starting position.
Other solutions I have noticed below have required that both sides take the 6th move in order to solve it. It would seem to me that if only white takes the 6th move, it could possibly be a solution since white will have only taken 5 moves from the stated starting position of the board. It all depends on whether that first white move that you have no control over counts or not. Anyways, here is my solution (forgive the notation, I am an amateur and it's the only notation I can figure out):
1w. e2-e4 (don't count this???)
1b. e7-e6 (black kings pawn forward one)
2w. e4-e5 (white pawn forward one)
2b. e8-e7 (black king forward one)
3w. b1-c3 (white knight)
3b. g8-f6 (black knight)
4w. c3-e4 (white knight)
4b. f6-e8 (black knight)
5w. e4-f6 (white knight)
5b. h8-g8 (black rook left one)
6w. f6-g8 (white knight takes rook, checkmate)
As you can see, if white doesn't have to count the mandatory move, the problem is solved. Given that an amateur like me figured it out this far, I suspect the problem requires that you count that first move, but perhaps somebody else can figure out a way to shorten what I have shown here by a half-move...
The author of the article did not say whether there was any calculable way of using some obscure trap (maybe a sacrifice of several pieces which would open up the board) which would allow black to escape from the computer's move progression that would ultimately leading to a black victory or draw.
...Open Source isn't the only answer -- but it's almost always a better value than the alternatives...
I waited for others to post the solution, then posed the question to some chess buff (but not really 'Net aware) friends of mine. I'll be merciful and give them the solution...in a year or two, after obsessing about this problem has driven them insane, shattering their will and priming them for mind control. ;)
No, I'm not serious. Except about taking the cheap (...er+faster=better) way out for getting the solution ('cause I already have enough problems to solve).
With Go, you can't lose in 5 moves except by resigning, and there's no computer software that plays Go well yet--it's too hard to brute-force it the way Chess programs tend to.
I worked on it for almost three hours, and had given up, when I had an idea. It didn't work, but I was in that state of mind where the inspirition was flowing, and the idea for the solution came to me. It was really slick. I stared and stared at the checkmate in disbelief, and began to almost get hysterical-- I had done in 3 hours what Kasparov and the other grand masters couldn't do at all. I checked the solution many times over. The pieces were set up correctly, the knight took the rook on the fifth move, and it really was checkmate- the king had no legal moves, and nothing could take the knight. But there it was. While I won't post the solution here until I get a confirmation back from ChessBase, trust me, it's the solution.
Here are a couple of minor hints:
- It's not a semantical trick- you can really solve this by playing through the five moves.
- Black wins
- Every move is essential-- there's no wasted half moves
- The knight does the mate-- no double or discovered checkmates
- No castling
- NO PAWN PROMOTION! >:
- No fancy or archaic rules were invoked-- it's just straitforward, legal chess!
Have Fun
Dan Rodgers
What about?
1.e2-e4 e7-e5 2.Ng1-f3 Qd8-h4 3.Nf3-g5 Bf8-c5 4.Ng5xf7 d7-d6 5.Nf7xh8 Qh4xf2# 0-1