computer chess

Computer Chess

Participate and you will reveal!
Funny name, real matters
[ Sign up | Log in | Guest ] (beta)
ccmcacollister ♡ 296 ( +1 | -1 )
Endgame Quiz: DIAGRAM & Question Hello my GK friends. I want to try a different concept here, of having this thread give the diagram for an endgame position ... but putting the solution for it in a separate thread. That way, everyone who wants to can have a shot at solving the endgame, without having any answers put into the same thread.
OF COURSE, I want to invite EVERYONE who has an endgame position (be it standard, or otherwise) to post their FEN diagram here, and to use the SOLUTION THREAD to show how to solve it, IF you have solved it.
IF No Solution is to be given by you, however, please indicate that with your diagram.
Hopefully, someone else will be able to fill in a solution for you, on the other thread.
***
Which brings up a matter of Format, to avoid confusion. Please see the numbering and indicator that I use in my following post, for example. 'Diagram" entry here should show:
[A] IN THE SUBJECT LINE: PUT A SHORT DESCRIPTIVE & THE NUMBER OF YOUR POSITION. (My position will be #1. Whoever adds the next position, will call it #2, etc.)
[B] IN THE MESSAGE PORTION OF YOUR POSTING:
1)Position (2)Who's move it is (3)What the last move was, if possible
(4)Whether they can find a solution from you on the other thread, or not.
(5) If you wish, you can also state any REASON you might have for posting the position; a common ending needing to be demonstrated & learned, an unusual or exception for its type of pieces, an enjoyable one you played, or such. But a reason is not required. Or you can state any unusual aspect to look for; or any hints, etc.

(6)BE SURE you are not asking about an active position from an ongoing game~!
********
In the SOLUTION THREAD, to post a SOLUTION, you should show:
[A] IN THE SUBJECT LINE:
(1) PUT the word SOLUTION in CAPS.
(2) THEN put identical info and number as you did in the first thread
IMPORTANT: ONLY THE SOLUTION POSTER should use the SUBJECT LINE this way. Others who wish to Question correctness of that solution, or add to it, or have other questions about it, or comments, or showing their own analysis, or any other discussion should just show the Number. Such as to refer to mine, just put "#1". Or leave blank here and refer to the number in your MESSAGE AREA.
All discussion is most welcome; we just need to be sure the official solution given can be easily discerned.

[B] IN THE MESSAGE PORTION: THE official SOLUTION POSTER should show:
(1) Show the mainline solution (aka "best play").
(2) Add any notes or sidelines you wish to.

(3) Other than the Official SOLUTION POSTER, any format is okay since content may vary from lines of play to Questions or other comments (like "what a terrible ending!"
or "this is unusual" or whatever :)
*************************
*****************
Now let me try to follow my own guidelines here! ....
If something is a little off the mark, don't worry about it. It doesn't need to be "BOOK" perfect.
I'm just trying to make it as easy for people to follow and understand as possible, without confusion when looking at the positions. (Remembering we have a worldwide language situation here :)
Regards, Craig A.C.

PS Hope we have a lot of posters! ...and solvers or students too!! Enjoy
########################
##############################
ccmcacollister ♡ 21 ( +1 | -1 )
This is the hyperlink . . . to the 2nd Thread, which has the solutions and analysis there. [Called Endgame Quiz SOLUTIONS]
-> gameknot.com
ccmcacollister ♡ 168 ( +1 | -1 )
KING+PAWN race #1


It is WHITE to move. Black's last move was pawn to a3
SOLUTION is given in other thread.

THIS ending is a frequent occurrence and should be understood well.
The Question/Objective= Can you win with White?
########

Hint: Winning with WT would mean being able to stop BL from Queening his pawn; or to be able to Checkmate BL or Win BL's Queen, if his a-pawn is/was able to reach a1 and Promote.
BL's objectives would be to avoid all those results! Or to create a stalemate position, or place WT in an unavoidable choice of making it stalemate or permitting BL to Promote. Or forcing WT to make a THREE TIME REPETITION OF POSITION due to a position where otherwise BL might Win, get Stalemated, or Queen his pawn. [A "3 Time Repetition" would allow BL to claim a draw under the tournament rule of that name.]
The ways to try to stop a pawn from promoting, when you have a Queen, are to:
*Get in front of it ...*Or Get behind it ...*Or force the enemy King in front of it
...* Or, pin it to the opposing King so it cannot move that turn. * Or a last resort of taking a draw by Stalemating, 3 Time Rep, 50 Move Rule, or Agreement.
............
Of these non-drawing options, being in front of the pawn is usually the surest, and often has the longest effect if the pawn is not immediately winnable. The closer your King is to the pawn the better, in such a case, since it would then need to help conquer the pawn or mate when the Queen cannot capture alone.
Always be sure to look at ALL checks available when playing a Queen vs a King and pawn(s).
Those are the General Principles of this Ending. And not necessarily all will be applicable to this position.
ionadowman ♡ 46 ( +1 | -1 )
Position #2 In part of his solution to the above (see (Position#1) the alternate "Solutions" thread) Craig mentions the situation in which Black doesn't have the extra b-pawn...
The situation might be something like this:
Position#2 (White to play: What result?)
w
Now, this sort of ending would be a draw if the White king were too far away. Is he close enough here to force a win for White?
Over to you...
Ion
ionadowman ♡ 82 ( +1 | -1 )
Position #3 Most of us probably know the technique for winning the endgame K+Q vs K+ NP on the 7th, or K+centre pawn on the 7th. Such a position occurred in an OTB pickup game three or four years back (I had the Black pieces, and had just promoted the pawn):
w
1.b7 Qa1ch 2.Kb6 Qd4ch 3.Ka6 Qd6ch 4.Ka7 Qc7
5.Ka8 Qa5ch 6.Kb8 Kg5 7.Kc8 Qc5ch 8.Kd7 Qb6
9.Kc8 Qc6ch 10.Kb8 Kf5 11.Ka7 Qc7 12.Ka8 Qa5ch
13.Kb8 Ke6 14.Kc8 Qc5ch 15.Kb8 (15.Kd8 Qc6 16.b8=N Qb7) ...
15...Kd6 16.Ka8 Qa5ch 17.Kb8 Kc6 18.Kc8 Qc7#

So far, so book. Given a position like this, How should White proceed?
Position #3:
w
But now for the real puzzle:
Suppose the White queen, instead of standing at e4, stood at f4. Could White win? Could White win with the Queen anywhere on the board (bearing in mind it is White to play), or are there squares from which White can not secure the win? If the latter, what squares are these?

Cheers,
Ion
ionadowman ♡ 46 ( +1 | -1 )
Simple endgames... ... often aren't so simple. Here is a famous finish from a game Ljubojevic-Browne, Amsterdam, 1972:
b
In this position, Black played
1...f5 and after White's response, 2.Kb4, agreed to split the point (i.e. the game was abandoned as a draw).
Starting from the diagram position, still with Black to play, what ought the result to have been?

I'll leave the solution for a day or two...
Cheers,
Ion
ccmcacollister ♡ 68 ( +1 | -1 )
RODOG vs CYRANO: ONGOING GAME "GK2500's"
I just want to point-out another endgame that you may find interesting to watch being played out, which is mentioned on another thread. Hyperlink below will take you to that thread if you wish to see it. Or the board number goes directly to their most recent position.

PLEASE be ABSOLUTELY CERTAIN to make no commentary of any kind about this game while it is STILL ONGOING~!
Between GK's 2 2500+ players RODOG & CYRANO
board #7001440
-> gameknot.com