white to play and win

Originally posted by crazyblue
After thinking about this and playing a game that leads to the position I think I've found a simple answer. Black's last move was KxNd8.

Explanation:
Neither player can win this game, because it's impossible to bring a pawn to the last rank and it's also impossible to checkmate the king with the pieces currently on the board.
Only Pa4 and Kd8 could ha 54. h8=N Rf1 55. e4 Rf2 56. e5 Kd8 57. e6 Rf7 58. Nxf7+ Ke8 59. Nd8 Kxd8
*t

Ke8xNd8, as well as Ke8-d8 or Ke8xQd8 or Ke8xRd8 are black's ONLY move towards a drawn position. Hence the position is drawn BEFORE that move according to FIDE law A.1.3.

Nice game construction, though.

edit. Oops, I didn't see that you already came to that conclusion, just looked at the game. Sorry for that.

Originally posted by Mephisto2
If a5-a4 had been played before, then Ke8-d8, or even Ke8xd8 (in check from queen or rook) would have been a forced only-move to a position which is drawn, and the game would have been over according law A.1.3 BEFORE making that king move. Nothing can be achieved by either player to release the position.

The move a5-a4, however forces a draw from a posi ...[text shortened]... ), preceeded by white pawn moves (e-pawn and g-pawn), releasing the position for the black king.

Releasing the position of the black King does not really answer the question of whether ...a5-a4 is a legal last move. It only shows that there is a possibility that the diagram position can occur in a legal game. The real proof lies in examining the forward play after retracting ...a5-a4. Is that position alive? If so, can you demonstrate a checkmate?

A "possible" checkmate exists after retracting 1...a4 but it is no more viable than the mate delivered with two knights - it requires a cooperative play on part of Black.
EDIT: Okay here goes the sooperative play: 1...Ke8 2.Ka6 Kd8 3.Bb7 Ke8 4.Bc8 Kd8 5.Kb7 Ke8 6.Ka8 Kd8 7.Bb7(a6) Ke8 8.Ba6(b7) Kd8 9.Bc8 Ke8 10. Bd7 + Kd8 11. Be8 Kc8 12. Bf7 Kd8 13. Bg8 Ke8 13.Kb7 Kd8 14. g5 Ke8 15. Kc8 a4 16.Bf7#

Originally posted by BigDoggProblem
Releasing the position of the black King does not really answer the question of whether ...a5-a4 is a legal last move. It only shows that there is a possibility that the diagram position can occur in a legal game. The real proof lies in examining the forward play after retracting ...a5-a4. Is that position alive? If so, can you demonstrate a checkmate?

"The real proof lies in examining the forward play after retracting ...a5-a4. Is that position alive? If so, can you demonstrate a checkmate?"

Agreed, and I thought that this was discussed above, explaining why the position after the alternative (to a5-a4) moves (King moves or takes on d8) is a dead one, hence the king move is excluded through A.1.3, leaving a5-a4 as only move. The 'releasing' part is there to complement the above conclusion, making a5-a4 legal. When you say that 'Releasing the position of the black King does not really answer the question of whether ...a5-a4 is a legal last move', do you mean that there is still some doubt whether the white position can be released too? That seems pretty obvious to me, but proof can be given if needed.

Originally posted by Mephisto2
"The real proof lies in examining the forward play after retracting ...a5-a4. Is that position alive? If so, can you demonstrate a checkmate?"

Agreed, and I thought that this was discussed above, explaining why the position after the alternative (to a5-a4) moves (King moves or takes on d8) is a dead one, hence the king move is excluded through A.1.3, le ...[text shortened]... on can be released too? That seems pretty obvious to me, but proof can be given if needed.

Releasing the position is the easy part. I was looking for what ilywrin just posted: A possible checkmate in the forward play, after retracting ...a5-a4. That is why ...a5-a4 is a legal retraction and Ke8(x)d8 is not.

Originally posted by ilywrin
A "possible" checkmate exists after retracting 1...a4 but it is no more viable than the mate delivered with two knights - it requires a cooperative play on part of Black.

Law A.1.3 isn't concerned with forced checkmates, but only possible checkmates.

The forward play you gave shows why -1...a5-a4! must have been the last move. Black needs to have that P tempo in the forward play to create a possible checkmate.

i can't believe you hijacked my thread for this silly discussion.
a much more practical rule to discuss is touch-move.
please list the correct procedure in the following cases

Basics
A.player touches two of his own pieces
B.player touches his piece and opponent's piece.
C.player touches opponents king
D.player touches piece he can not legally move becuase he is already in check
E. player touches piece that can not move because it is pinned (to his king
F. player touches piece that has no legal moves but no check is involved

Intermediate
A.player moves king through check
B.player moves king into check
C.player castles after moving king
D.player promotes pawn and then touches his piece that is off the board
E.player touches piece off the board then promotes pawn
F.player moves his pawn to e.p. square but does not touch opponents pawn

Advanced
A.player completes (presses his clock) a move with a pinned piece
B player makes an illegal move but realizes b4 he presses his clock
C.player completes a move that leaves his king in check
D.player completes a capture with a pinned piece
E.player completes a move of a piece in an illegal manner (move a rook like a knight etc.)
F.player moves out of turn
G.player touches a piece and then accepts a draw offer (from opponents previous move)
H.player has less than 5 min remaining when he completes a move that leaves his king in check
I. both players complete a move while one is in check.
J.player places a queen on a promoting square but does not touch his pawn
K.player places queen and then touches promoting pawn

i don't know some of the answers to the advanced questions but the basics every player should know as they come up fairly often.

Sillyness is in the eye of the behoulder.

Originally posted by vaginis
i can't believe you hijacked my thread for this silly discussion.
a much more practical rule to discuss is touch-move.
please list the correct procedure in the following cases

Please ignore the two chess problems I presented and continue misrepresenting my tangent as a mere discussion of the rules.

Originally posted by BigDoggProblem
Please ignore the two chess problems I presented and continue misrepresenting my tangent as a mere discussion of the rules.

1. i take note of your abusive tone and language
2. your so called problems do not involve anything practically useful
a draw is a draw.
3. in your second puzzle the position will never be achieved in a game between two players who are both trying to win not to mention that the game is drawn prior to the last move in that position and would be declared a draw by any judge
4.in the first puzzle either the game was clearly won by one side and they simply gave away material or the game was clearly drawn and therefore such a position interests me not at all.
5.finally the tangent was started as a discussion of the rules (a rather frivilous discussion of a side effect of a rule created for a technical reason and not to fill any partiular need)

if you wish to avoid my criticism of such silly wastes of time in the future i suggest starting your own thread instead of hijacking mine
although i must say i was mostly kidding at the time, and didn't particular mind seeing as how the original puzzle was solved.
if you're wondering why i'm reacting in such a belligerent manner please see point #1

Originally posted by BigDoggProblem
There is no insufficient losing material rule. You're confusing two USCF rules:

1) Insufficient Losing Chances. A player may stop the clock, and claim that he has insufficient losing chances. The TD may either a) grant the claim outright, declaring the game a draw, or b) place a digital clock with time delay on the game. If no progress is made, he ...[text shortened]... ed, and K/Q v. K/R is a theoretical win for the Q side in most cases (as Mephisto pointed out).

I said I wasn't sure. It's been almost 3 years since I saw the rule called in a game and don't own a copy of the USCF rule book.

And my point wasn't directed directly at the game. It was directed at PBE6's variation. Which if the pawn promotes to a rook, it would be drawn by insufficient losing chances, even if a digital clock was used.

Originally posted by Mephisto2
Where did you get that from? Anyway, it is nonsense. There is no such rule. And K+Q vs. K+R is a won endgame, with a few exceptions where a stalemate can be forced.

The solution given is correct.

Please look at the line I was replying to before calling it nonsense.. In the line I was replying to PBE6 had the promoting pawn equalling a rook. Thus leaving a pair of rooks on the board.

Now, from my general understanding, this would usually equal a draw, no?

no this is not a draw. a player can claim it is a draw based on insufficient losing chances (in this case white will proceed to win). but to illustrate the point consider a position where black has just captured a queen but his rook is now hanging can he claim a draw?

Originally posted by GalaxyShield
[b]Please look at the line I was replying to before calling it nonsense.. In the line I was replying to PBE6 had the promoting pawn equalling a rook. Thus leaving a pair of rooks on the board.

Now, from my general understanding, this would usually equal a draw, no?[/b]

Whatever yuwere replying to, stating: "..... It's the same with Q+K vs Q+K. I think you're only given 1 move after you promote the pawn to either get an edge in material/have a clear win. Maybe not even that." is nonsense.

Originally posted by GalaxyShield
And my point wasn't directed directly at the game. It was directed at PBE6's variation. Which if the pawn promotes to a rook, it would be drawn by insufficient losing chances, even if a digital clock was used.

How can PBE6's variation result in a correct ILC claim when white has a forced win after the Rook promotion??