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Two possible solutions for a tactics quiz

Sometimes there are multiple solutions for a tactics quiz, but only one of them is considered as the right one, may be with the same final position, i.e. different move order with the same final position. Other times there are two mate solutions and only one is considered as the right one.

It would be a very good feature if any of the solutions could be considered as the right solution.

Thank you in advance.

Juan

Give examples and report them to lichess staff :). Anything else wont really help

That’s what I am thinking sometimes as well. Just switch on the engine and then you will learn why a is right and b is wrong.

In fact that is extremely important to get the moves into the right series.

Ok, I will report them. So far I have had more than one. How sould I report them? Is there a notation for that? I don't know how should I report the initial position for the quiz. For the moves there is the normal notation but to describe the initial position ...

As CM Sarg0n says is Good to switch on the engine and with its help I have already discarded wrong solutions. I have done it multiple times but sometimes there are other right solutions.

i did that as well but sometimes it's just somewhat frustrating to see that you found a really good move giving you +3
then you fail because there was a +4
sometimes it's just counter intuitive because the engine solution even if objectively better will give you more difficulties
then the "not so good" other winning move. though those are rare most of the time the engine solution is clearly to be prefered.

Provide an example, unless that happens there are never no two solutions. Period. ;)

(technical issue: just copy link, say number of puzzle, name the game ... )

First of all, any move that gives away some or all of your advantage is a bad move and cannot be the solution to a puzzle. The point is to find the best move. If going from +4 to +3 is OK, then how about down to +2? +1? Where is the line drawn? If giving away some of your advantage on one move is no big deal, you’ll probably just give the rest away on subsequent moves. To take suboptimal moves to would contradict and undermine the very purpose of the puzzles.

Furthermore, the number of people who have complained about puzzles and been wrong in these forums is quite high, while the number of problem puzzles is very, very tiny. So until you provide links, the obvious and most certainly correct assumption is that you personally are wrong, and the puzzle is fine.

To elaborate on what @Chuck_Fess wrote, it is important to keep in mind that the engine starts assigning a "winning" evaluation earlier than many/most humans would.

Say, if you have a very complex, but currently materially balanced position with a tactic that will lead you to win your opponent's queen in 5 moves and another tactic that will "only" win a rook.

For a human, the starting position may be labeled "even", and both resulting positions as "winning". But for the engine, the starting position is a +9 already since it already prices in the queen you can forcibly win. If you instead only win the rook, the evaluation will drop by -4, thus it will say you made a mistake. Despite actually still arriving at a "won" position that in human terms is "better" than the initial one because the uncertainty whether you find the tactics has been removed (a factor that does not exist for the all-seeing engine).

@ProfDrHack : I solved a few hundred puzzles on Lichess and I never had one with the scenario which you describe here.
On chesstempo.com I had several of these positions where alternative solutions existed. If you try one of these alternative solutions, the computer simply tells you that there is a better solution and you can then try to find it. You didn't fail.
Every line which ends with an advantage of more than +2 is considered an alternative line.

I had some scenarios on Lichess where you have 2 good candidate moves which seem to be winning. Sometimes it is hard to decide which one is correct. In all of these examples I later found out that the alternative line gave you only an advantage of +1.5, while the best line was +3 or better. These puzzles are the hardest for me to solve. But you learn a lot from those examples because you can then try to find out why the computer comes to this evaluation.

@jmss0906: You write that there are puzzles with an alternative second mate and that you fail if you try this line. To be honest, I don't believe that you can come up with examples for this. I also had puzzles on Lichess where I thought that I found a mistake and the puzzle must be wrong. Later I always found out that I was wrong. I simply had missed something very important in the position. For example, a few days ago I thought that I had found a puzzle which must end in a draw. Even after 30 minutes, I was not able to spot the correct answer. Then I realized that I can simple capture a pawn en passant. I missed this because I didn't check the move list.

Reconnecting