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Training 77006 - drawn ending? #4060

Closed abrogley closed 6 years ago

abrogley commented 6 years ago

https://lichess.org/training/77006

The given solution is:

  1. h5 gxh5
  2. g6 hxg4
  3. g7 g3
  4. g8=Q

And this gets white the queen first. But after 4. ... g2 can black not maintain a draw with the constant threat of promotion?

Other commentators on game https://lichess.org/B3LpEChO/white seem to agree.

ddugovic commented 6 years ago

I wonder if https://github.com/clarkerubber/Python-Puzzle-Creator can be enhanced to detect fortress positions somehow...

teeveeJS commented 6 years ago

I am not sure this is the best forum for discussing whether a given puzzle is won or drawn. Improving the puzzle creator to detect fortresses would require fundamental changes to Stockfish itself. At any rate, the puzzle's solution should stand: the correct variation gives white the best winning chances and nowhere does the puzzle ask for a forced win (as far as I can see). As such, I suggest this Issue be closed.

ddugovic commented 6 years ago

The puzzle requires: "Find the best move for white" however 50. h5 etc. draws and 50. Nf6 also draws.

As for fortress detection, Stockfish has already been enhanced...

niklasf commented 6 years ago

@abrogley Thanks. I disabled the puzzle, so it will no longer be automatically selected.