In order to organise the forum a bit, I propose to make one dedicated topic to report mistakes in puzzles, mostly other move orders or alternative winning sequences.
I found this one in puzzle 832 (lidraughts.org/training/832): except the intentional solution white can play 3328 2520 (or 2520 3328) and 4440, winning one piece.
Puzzle 1079: (lidraughts.org/training/1079) except taking a direct combination, also 3530! as a first move appears to be winning. :)
Puzzle 1487 (lidraughts.org/training/1487) has a move order problem: on the 7th move, 3933 is considered a mistake.
Puzzle 1446 (lidraughts.org/training/1446) has a different intended solution by the author of this position, which results in a sharp endgame... The correct move according to Lidraughts is a 'cook' (see en.wikipedia.org/wiki/Glossary_of_chess_problems).
Puzzle 1491 (lidraughts.org/training/1491) has an alternative on the 4th move: 4943 is also winning, but considered a mistake.
Hi @simpaticheski and all,
I agree, it would be better to get all the puzzle feedback in one topic.
Thnx for the feedback! The puzzles are disabled.
Sadly but understandably, it is not rare to find mistakes, deviations etc. in draughtsmaterial in general (compositions and other). If the intended line is also objectively winning, it ofcourse should be considered correct in the puzzle. That said:
What would you consider to do with a 'cook' problem as you mention this specific category of puzzleproblems?
And to all:
Keep up the good work, being so sharp to find these mistakes and share it! A lot of them are very hard to find, and sometimes beautiful to see. To be transparent: I can happily tell you that less than 5% of the puzzles had to be corrected so far, and the percentage seems to go down (over 2000 puzzles, Frisian included). We will keep adding puzzles to the website in the coming time. I will keep a close eye to this topic and the forum as a whole to process all feedback. And again, it would be wonderful to see all the puzzlefeedback in this topic.
Hi @BumperBalloonCars, thank you very much for you elaborate reply and actions! I will come back to you tomorrow.
For now, one more imperfections I spotted:
Puzzle 1627 (lidraughts.org/training/1627): however cute the intended last shot may be, plainly moving to king wins convincingly as well.
Puzzle 734 (lidraughts.org/training/734) offers some choice on the 3rd move, most probably 3137 and definitely 2429 are winning as well.
On 1627 the idea was that moving to king simply loses the king immediately, and the winning line is a much clearer win, objectively clearly better continuation. But looking at it more closely now, 8-2 is way to good as well to count it as a mistake.
Puzzle 734 has indeed too many winning lines.
We'll disable them.
I immediately believe that only less than 5% of the puzzles has to be corrected, since the vast majority of the puzzles are really nice! I am grateful - and with me many Lidraughts users, I presume - to have such an easy training possibility.
In response to your question about 'cooks': if the cook (co-solution) is not too obvious, I would keep the problem, considering both the intended author solution and the cook as winning lines. If the cook is too easy (like a 1-for-3-shot), I would disable the problem. But, of course, this "obviousness" is not a very practical measure.
I am also curious about the possibilities of the puzzle applet:
- is it possible (for the webmaster) to add comments to the solution? In this way it can be indicated whether the move played is the indicated author solution, or a cook. It is cumbersome to add comments to all the puzzles, but for some it might be of added value. If possible, this could be considered for clarifying 'cooks'.
- sometimes a shot involves a choice for the enemy colour; is it possible to ask for the solution after each possibility within one puzzle? Again, it is cumbersome to do this for all puzzles, but might be worthwhile for some.