lidraughts.org

Mistakes in puzzles

Puzzle 1371: The forcing 1. 31-27 is also winning. Afterwards 22-18 and then several moves to win.

Puzzle 471: 12-17 instead of 21-26 as a waiting move is also winning.

I will disable all puzzles that are brought up, except the following:
600: seems to be correct, also on move 4. 35-30.
609: It's quite useless to give away two extra pieces. It is also winning, but in my opinion not a wrong puzzle.
726: disagree, going to King is way to strong in comparison, winning just one piece results in just +1.1 after longer evaluation.
1177: Somehow the variant 27-21 is resulting in an advantage of just +0.4 (depth 33) while the main line result in +1,5 (depth 33).
1180: I understand your point, but the puzzle is not incorrect. I choose to keep it this way.

All the other ones are clearly wrong or arguable. Some will be corrected, some can be improved and some won't be back as a puzzle.

Thnx to Malacia, Tim and jeffreyq2

@BumperBalloonCars Some replies to your comments:

600: I think he meant move 5 instead of 4, it's a bit confusing because first white move is move 2 (which is also forced).

1177: You're right, of course, that 27-22 is undeniably stronger. I just wanted to point out that from a solver's perspective this is highly frustrating because it's not clear at all why 27-22 is better than 27-21, even after executing both lines. Also, keep in mind that Scan's evaluation doesn't say much about any practical chances, _especially_ at depth 33. At lower depths the scores are a lot closer. The puzzle is about seeing the combination to 1, not about somehow being able to tell that 33 moves after the combination is over 27-22 wins and 27-21 doesn't.

1180: I don't really know what to say about this one... Everyone can see that 2x13 is the author's intention. It makes the puzzle more interesting, and it is more realistic because it's easier to see that 3x12 is losing. It's understandable that you missed it the first time, but just fix the puzzle and move on.

Puzzle 1354: the only accepted solution is not the intended one, the intended one starts with 27-22.

Puzzle 663: 38-33 without 37-31 is also winning.

Puzzle 1150: 28-22 and 22-17 is also winning, although not with a direct shot. Scan gives it a +3.5 for white with depth 35.

Reconnecting