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Games determined by their last move

Games determined by their last move

Posers and Puzzles

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Originally posted by c0lefalk
Wow, twelve minutes.
Hey, now, don't talk like that. 11.5 of those minutes were finding the thread, honest! 😉

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A hint to the Rh1# one please?

1 edit
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NOOO!!!! If you give a hint, send to them in a message please 🙂

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I've written a program to search for these games; the only four 3-move games with unique ending moves end in

3. ... Bxb3+
3. ... Bf6+
3. ... Rxe5+
3. ... Qd4#

It's working on 3.5 move games now.

2 edits
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1. c3 d6
2. Qb3 Be6
3. Kd1 Bxb3+

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1. d3 e6
2. Kd2 Be7
3. Kc3 Bf6+

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1. e4 h5
2. Qxh5 Rxh5
3. e5 Rxe5+

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1. f3 e5
2. Kf2 Qh4+
3. Ke3 Qd4#

1 edit
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4. Ra8 and its symmetric partner
4. Rh8 are the complete list of unique ending moves for 3.5-move games.

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Nice, the question is how did you find them?

1 edit
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Originally posted by heinzkat
Nice, the question is how did you find them?
As I mentioned above, I wrote a program to exhaust all the possibilities. To have it look at all 4-move games would take the better part of the day, so I'm trying to find a way to speed up the algorithm.

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1. a4 b5
2. axb5 Nc6
3. Rxa7 Rb8
4. Ra8

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Nicely done.

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... and similar of course
1. h4 g5
2. hxg5 Nf6
3. Rxh7 Rg8
4. Rh8

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Originally posted by GregM
Nicely done.
The writing of the fens took more time than solving it. But what kind of program did you write?