01 May 07
Originally posted by lauseyI think getting the opposition is right, and white wins.
Worked out that getting the opposition (1. Kd3) will allow black to get the pawn on a5 too easily.
I think 1. b3.
If black retreats up the d-file, white just chases him 2Kd4 Kd7 3Kd5 Kd8 4Kd6 and now black has to go left or right.
If instead he goes to the c-file at any point in the above sequence, or after 4Kd6 Kc8, then white will queen first - count the moves: white K d-file (any of d3 to d6) to h6 4 moves, K out the way of pawn 1 move, pawn h5 to h8 3 moves, total 8 moves; black K c-file to a5 minimum 2 moves, K out of the way 1 move, pawn a5 to a1 4 moves, minimum 8 moves. But white starts, so after they both queen it is his turn and he can go Qh8xa1.
If black goes to the e-file instead, then white will queen in 7 or 8 (Qd3-a6 takes 4 or Qd4/d5/d6-a6 takes 3, K out of way 1, pawn a5-a8 3, total 7 or 8); black takes 9 (K e-file to h5 3, K out of way 1, pawn h6 to h1 5).
That's the key to these type of pawn endings: just count each side's moves. The two sides don't interact at all, so you don't have to calculate 1.. Kc5 2 Ke4 Kb5 3 Kf6 Kxa5 etc, just count up and see who gets there first.
1Kb3 loses because black will win the a-pawn and white is too late to run to the king side. 1..Kc5 2Ka4 Kc4 and white has to give way.
01 May 07
2 edits
Originally posted by Restless SoulIt's a draw.
[fen]8/8/p6p/P2k3P/8/8/2K5/8 w - - 0 1[/fen]
Who is winning? White to move
Kd3 ..Kc5
Kc2 ..Kb5
Kd4 ..Kxa5
Kc5 ..Ka4
Kc4 ..a4
Kc3 ..Kb5 (**or allow eventual stalemate on a1)
Kb3 ..a4+
Ka3 ..Ka5
Ka2 ..Kb4
Kb2 ..a3+
Ka2 ..Ka4
Ka1 ..Kb3
Kb1
Unless i missed something right at the beginning, this is clearly a draw. White can capture the a pawn and make it across in time to guard g2.
**It doesn't matter if black releases his king from the edge of the board on this move or later on after a couple of pawn moves, the essence of the position is the same. Both Kings have to travel just as far to reach their objective on the kingside. It's 8 moves no matter which route you take....
01 May 07
Originally posted by MarinkatombHave you got some typos in this? Black's first move as you wrote it is illegal, and a bit further down white's king jumps from c2 to d4.
It's a draw.
Kd3 ..Kc4
Kc2 ..Kb5
Kd4 ..Kxa5
Kc5 ..Ka4
Kc4 ..a4
Kc3 ..Kb5 (or allow eventual stalemate on a1)
Kb3 ..a4+
Ka3 ..Ka5
Ka2 ..Kb4
Kb2 ..a3+
Ka2 ..Ka4
Ka1 ..Kb3
Kb1
Unless i missed something right at the beginning, this is clearly a draw. White can capture the a pawn and make it across in time to guard g2.
But I think what you are suggesting is that white should defend the queen side when black attacks the a-pawn in order to play for a draw. But instead, white can win by counter-attacking on the king side - see my post above.
01 May 07
1 edit
Originally posted by d36366Ah yes, that's really obvious now that i look at it. White can capture on either side and Queen first, obviously being super careful not to put his King on g7 or b7 as black would Queen with Check...😉
Have you got some typos in this? Black's first move as you wrote it is illegal, and a bit further down white's king jumps from c2 to d4.
But I think what you are suggesting is that white should defend the queen side when black attacks the a-pawn in order to play for a draw. But instead, white can win by counter-attacking on the king side - see my post above.
Have you got some typos in this? - Sorted...
02 May 07
2 edits
White wins with 1.Kd3, because his pawns are two ranks more advanced than black's. That means that after 1. ... Ke5 (resp. Kc5) white plays 2.Kc4 (resp. Ke4) threatening to capture and promote enough steps in advance to win (he promotes with coverage of square h1 resp. a1). If black tries towards the same side with 2. ... Kd6 then 3.Kd4 gains the opposition, and black won't be able to regain it because the white pawns on a5 and h5 will prevent him. The same happens if black moves to the 6th rank in the first move. White takes and keeps opposition.