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        riddles >> easy >> Chess Positions
        
(Message started by: Benoit_Mandelbrot on May 19^th, 2004, 9:44am)

Title: Chess Positions
Post by Benoit_Mandelbrot on May 19^th, 2004, 9:44am

What is the correct sequence of moves for black to get and retain a queen, ensuring a victory?

White started from the bottom, and it's black's move. What are the correct moves?

BP is black pawn, WP is white pawn, WK is white king, BK is black king.

People can keep adding to this one, submitting different positions and such, so we don't clutter the easy puzzles with all chess. We can keep all positions in this post. I'll be adding more for sure. Feel free to add your own position that people can solve.

Title: Re: Black to move
Post by Aryabhatta on May 19^th, 2004, 9:56am

Move the Black King is the same vertical file as the White king.
White will now have to move his pawn. You can move your pawn in such a way that the pawns will be blocked and it will be your move. You now move the BK back to its original spot. WK has to move now.. and you can queen your pawn in 2.

Nice!

Title: Re: Chess Positions
Post by Benoit_Mandelbrot on May 19^th, 2004, 10:21am

Correct!

How about this one?

It's white's move, and started from the bottom. What is the best move for white, that will ensure queening of the white pawn and removal of the black pawn?

Title: Re: Chess Positions
Post by THUDandBLUNDER on May 19^th, 2004, 10:24am

For the first one Black wins even more quickly if it is White to move!

The second one involves mutual zugszwang, also known as trébuchet.

Title: Re: Black to move
Post by Leon on May 19^th, 2004, 10:36am

on 05/19/04 at 09:56:41, Aryabhatta wrote:

Move the Black King is the same vertical file as the White king.
White will now have to move his pawn. You can move your pawn in such a way that the pawns will be blocked and it will be your move.

What am I missing here? I don't see that working:

Move BK from D3 to C3 (1 space to the left, vertical over the WK).
WP from A2 to A3.
BP from A7 to A6.
WP to A4

It's now blacks turn. If they advance BP to block the WP, it's a draw since white cannot move.

If you move the BK to the side, white can advance WP (blocking it) and it's now blacks turn. If BK is moved back over the WK, it's a draw. If BK moves off of BP (only move other than over the top), BP is lost.

What am I missing?

--- Nevermind - react to his start of a single advance or a double with the opposite - DUH ---

Title: Re: Chess Positions
Post by THUDandBLUNDER on May 19^th, 2004, 10:49am

Quote:

--- Nevermind - react to his start of a single advance or a double with the opposite - DUH ---

Are your initials really DUH?

:o

Title: Re: Chess Positions
Post by Leon on May 19^th, 2004, 11:24am

on 05/19/04 at 10:49:35, THUDandBLUNDER wrote:

Are your initials really DUH?

:o

They sure feel like it somes days. If it wasn't poor form, I'd delete that post entirely.

Title: Re: Chess Positions
Post by THUDandBLUNDER on May 19^th, 2004, 11:40am

Quote:

If it wasn't poor form, I'd delete that post entirely.

No, I was only joking.
Of course, you are quite right to query anything that you don't understand.

;)

Quote:

BP from A7 to A6.

Instead, Black plays A7 to A5. :P

Title: Re: Chess Positions
Post by Aryabhatta on May 19^th, 2004, 12:07pm

on 05/19/04 at 10:21:44, Benoit_Mandelbrot wrote:

Correct!

How about this one?

It's white's move, and started from the bottom. What is the best move for white, that will ensure queening of the white pawn and removal of the black pawn?

I think if white is able to kill the black pawn he should be able to force a win.

To do that :
white move: c5-d6. threatening an immediate kill of the black pawn,

forcing:
black move: g4-f4

Now white moves d6-d5 and black's pawn is dead the next move.

After that i think it is a well known endgame.. is it?

Title: Re: Chess Positions
Post by Benoit_Mandelbrot on May 19^th, 2004, 12:30pm

The best way for white would be to move the king up and to the right, allowing the black king to move towards the white pawn. Then the white king moves down to protect the white pawn, and threatening the black pawn. The black king must move away, and the white king takes the black pawn, and clears a path for the pawn by preventing the black king from moving near the pawn. Since the black king couldn't move back up to protect the black pawn because of check by the white pawn, it must move away.