White to move. Is this a win, loss, or draw for white. This requires considerable effort and deep calculation.
7k/1p4p1/3p4/3p3P/7P/2P2P2/8/6K1 w - - 0 1
I'm not sure that I made the best moves for black. I got a draw.
1.Kf2 d42.c4 Kh73.Kg3 Kh64.Kf4 Kxh55.Ke4 Kxh46.Kxd4 Kg37.Ke3 Kg28.f4 b69.Ke2 Kg310.Ke3 g611.Ke4 Kf212.Kd5 Kf313.Kxd6 Kxf414.Kc6 g515.Kxb6 g416.c5 g317.c6 g218.c7 g1=Q+19.Kb7It's a draw.
Without a deeper look at the entire line, Alena, I can't be sure it is actually drawn, but I stopped at move 7 in any case- black has a stronger immediate move at move 7 in reply to 7.Ke3. I am really only uncertain whether or not black can transpose to the same line after 7. ....Kg2?!
On further consideration, I do think 7. ....Kg2 is a flat out error. If you can work out black's win after 7. Ke3, you might be able to find white best play at move 1.
Thanks for your advice. I'll try to solve it tomorrow.It's time to sleep for me.
White needed a tempo to draw this game.
1.h6 gxh62.Kf2 Kg73.Ke3 Kg64.f4 Kf55.Kd4 Kxf46.Kxd5 Kg47.Kxd6 Kxh48.Kc7 Kg59.Kxb7 h510.c4 H411.c5 h312.c6 h213.c7 h1=Q+14.Kb8It's a draw.
So, where did the extra tempo come from? Black can, of course, just reply with 1. ...g6 rather than capture at h6 with the pawn, thus leaving the fundamental structure of the king side unchanged- the black king can still march and clean up the h-pawns, the g-pawn is still a g-pawn, the white f-pawn is still the same distance from the black king, and black can still play d4 in response to Kf2. Consider comparing the positions that arise in your first line and those that arise after 1.h6!! g6 2.Kf2 d4 etc.
1.h6 g62.Kf2 d43.c4 Kh74.Ke2 Kxh65.Kd3 Kh56.Kxd4 Kxh47.Kd5 g58.Kxd6 Kg39.Kc7 Kxf310.Kxb7 g411.c5 g312.c6 g213.c7 g1=Q14.c8=QIt's a draw.
1.h6 gxh62.Kf2 d43.c4 Kg74.f4 Kf65.Ke2 Kf56.Kd3 Kxf47.Kxd4 b68.Kd5 Ke39.Kxd6 Kd410.Kc6 Kxc411.Kxb6 Kd412.h5 Ke513.Kc5 Kf514.Kd5 Kg515.Ke5 Kxh516.Kf5It's a draw.
Alena, consider the following, representative lines:
1.Kf2 d42.c4 Kh73.Ke2 Kh64.Kd3 Kh55.Kd4 Kh46.Kd5 Kg37.Kd6 Kf38.Kc7 Ke49.Kb7 Kd4 Position after 9 moves is 8/1K4p1/8/8/2Pk4/8/8/8 w - - 0 1
1.h6 g62.Kf2 d43.c4 Kh74.Ke2 Kh65.Kd3 Kh56.Kd4 Kh47.Kd5 Kg38.Kd6 Kf39.Kc7 Ke410.Kb7 Kd4 Position after 10 moves: 8/1K6/6p1/8/2Pk4/8/8/8 w - - 0 1
Can you demonstrate and explain why these two final positions are different? These two positions in these lines represent the real principle underlying this beautiful Ryabinin study. Why does white lose the first one, but draw the second? At a glance, it appears to make no sense, right, but when you study them in detail, the reason becomes clear.
The two lines differ by the position of the pawn. It's very important because the pawn plays a key role.In the first line the pawn guard f6 and the white king can't come near it and catch the pawn.In the second line the pawn doesn't guard f6 and the white king come and grab the pawn.
10.Kc6 Kxc411.Kd6 Kd412.Ke6 Ke413.Kf7 g5The position is lost for white.
11.Kc6 g512.Kd6 g413.c5 g314.c6 g215.c7 g1=Q16.c8=QIt's a draw
11.Kc6 Kxc412.Kd6 Kd413.Ke6 g514.Kf5 g415.Kxg4It's a draw
11.Kc6 Kxc412.Kd6 Kd413.Ke6 Ke414.Kf6 g515.Kxg5It's a draw.
I'm looking forward to your next puzzles.
Well done, Alena.