- Blind mode tutorial
lichess.org
Donate

Lichess' Number 1 puzzle according to google, and it's WRONG!!!!!

#3

@MrPushwood
The answer that I came up with and that the computer says is correct the puzzle says is fail.
I though the pictures made it pretty clear.

@MrPushwood The answer that I came up with and that the computer says is correct the puzzle says is fail. I though the pictures made it pretty clear.
#4

@ThighBald Stockfish used in the analysis was not computing deep enough to find the faster win. With deeper analysis we get that 71.Rc5 is mate in 9 and that 11.Rg5+ is mate in 11. This would mean that 71.Rc5 is the best move.

That aside, 71.Rc5 forces Black to either play 71... Nxd6 to stop the d-pawn or 71... Nd2 (as in puzzle solution when I played it), in which case the d-pawn will queen soon.

The puzzle has an up/down vote of 0 ! Vote it down if you wish.

Unclear why google found this puzzle as a top hit.

---Edit
The other thing that may be confusing is that #8 in your pic. It means mate in 8 after 1.Rc5, the total sequence computed before White's move is mate in 9.

71.Rc5 Nxd6 72.Kxd6 Kf6 73.Rg5 Kf7 74.Rf5+ Kg8 75.Ke6 Kg7 76.Rg5+ Kh7 77.Kf7 Kh6 78.Ra5 Kh7 79.Rh5#

@ThighBald Stockfish used in the analysis was not computing deep enough to find the faster win. With deeper analysis we get that 71.Rc5 is mate in 9 and that 11.Rg5+ is mate in 11. This would mean that 71.Rc5 is the best move. That aside, 71.Rc5 forces Black to either play 71... Nxd6 to stop the d-pawn or 71... Nd2 (as in puzzle solution when I played it), in which case the d-pawn will queen soon. The puzzle has an up/down vote of 0 ! Vote it down if you wish. Unclear why google found this puzzle as a top hit. ---Edit The other thing that may be confusing is that #8 in your pic. It means mate in 8 *after* 1.Rc5, the total sequence computed before White's move is mate in 9. 71.Rc5 Nxd6 72.Kxd6 Kf6 73.Rg5 Kf7 74.Rf5+ Kg8 75.Ke6 Kg7 76.Rg5+ Kh7 77.Kf7 Kh6 78.Ra5 Kh7 79.Rh5#
#5

@jomega
Thanks for your well thought out response.
Something that occurred to me after reading your post is that on the analysis board it says the engine is thinking 21 nodes deep. But nodes I guess are HALF moves so that's why it's not seeing # in 11 because 11x2 is 22, one more than the engine could see.

Still I like Ng5 better because it prevents black from preventing white from having his queen, although you've got a spare pawn there anyway.
Yea curious as to why this would be the google number one, I'm guessing because people had links to this puzzles somewhere.

@jomega Thanks for your well thought out response. Something that occurred to me after reading your post is that on the analysis board it says the engine is thinking 21 nodes deep. But nodes I guess are HALF moves so that's why it's not seeing # in 11 because 11x2 is 22, one more than the engine could see. Still I like Ng5 better because it prevents black from preventing white from having his queen, although you've got a spare pawn there anyway. Yea curious as to why this would be the google number one, I'm guessing because people had links to this puzzles somewhere.
#6

@ThighBald You just found one of the largest problems with puzzles: There can be multiple winning solutions, but only one of them is "correct". I strongly dislike it since puzzles do not teach you to play well, they teach you to play like Stockfish (the problem being that humans are not Stockfish).

@ThighBald You just found one of the largest problems with puzzles: There can be multiple winning solutions, but only one of them is "correct". I strongly dislike it since puzzles do not teach you to play well, they teach you to play like Stockfish (the problem being that humans are not Stockfish).
#8

@Puredication I think this puzzle is a good example of that problem, yes. That's because in this puzzle the difference only shows up with a computer evaluation that goes to 22 nodes wtf, and it's a difference of mate in 10 or mate in 11.
Where it isn't so bad is in puzzles for example where one move could win a rook but the other candidate move could win the queen in the space of just a few moves.

@Puredication I think this puzzle is a good example of that problem, yes. That's because in this puzzle the difference only shows up with a computer evaluation that goes to 22 nodes wtf, and it's a difference of mate in 10 or mate in 11. Where it isn't so bad is in puzzles for example where one move could win a rook but the other candidate move could win the queen in the space of just a few moves.
#9

TLDR: For best chess improvement, do deliberate practice on the puzzles and go over them with a strong player.

@ThighBald @Puredication Good points in #8 and #6. I do a lot of puzzles with my students. There are a number of issues using Lichess puzzles, and I've seen it on other sites as well. You have mentioned some. I'll try to make a list here, but let me say first that there is nothing to compare with having a strong player going over the puzzle with you. Unlike the computer, the strong player can talk to you about the chess ideas that are in the puzzles. He can help you explore why the motifs in the puzzle work, and what would make the motifs not work. In a phrase, "deliberate practice".

Of course for many people the points below are irrelevant. They are playing the puzzles for fun. They get it right, they feel good. They get it wrong, well on to the next puzzle.

So some problems with puzzles:

  • Multiple solutions, but only one correct one.
    I've seen sites where you do not fail the puzzle if you get an alternate solution. I've also see ones where there is a point system for each move and the best move gets the most points etc. What I'm always asking my students is the plan behind their move. The motifs being addressed. For example, in this puzzle above, the motifs are queening a pawn and weaving a mating net. Very few people can see the mate in 11 with 71.Rg5+. That move allows Black to move the King closer to the pawn. Hopefully the student is not playing that move just for the sake of a check! The motif of creating a crises for the Black Knight over the promotion theme is the thing to take away from this puzzle. After 71.Rc5, the Knight cannot get back to stop the pawn and so must exchange itself for the pawn or run away. And then the pawn is going to Queen and mate will follow quickly. There is no need to be calculating either the 9 or 11 move mate. Good players do not calculate that in this position. They'd instantly play 71.Rc5 for the reasons above. They've seen the motifs before.

  • The puzzle ends without a clear resolution.
    The student may have no idea how to proceed after getting the puzzle correct. On to the next puzzle, is usually what they do. If they do that, they are missing an opportunity. After having spent time to solve the puzzle, why not spend a little more time and continue with deliberate practice. If you do not know how to win from the position at that point, perhaps you should investigate it. Work it out with computer help, or much better, get a strong player to help.

  • The puzzles can be solved by guessing with no understanding.
    This is obviously not the way to get better at chess.

  • The solution involves moves only a computer would play.
    As @Puredication pointed out in #6. This happens for both sides. I've seen puzzles where, after the initial "correct" move, the computer plays a move for the opponent that a human would almost certainly not play! Examples abound. Spite checks are my favorite. Second favorite is the computer tossing its Queen away because it sees that it is going to lose it anyway, many moves later! Even if a human saw that, he'd hold the Queen in the hope that his opponent has not seen the win of the Queen!
    Also, the computer will gladly take a position it has calculated gives it more points, even though it will be hard to defend tactically by a human. Again, a strong player going over the puzzle with you is the best solution to this issue.

  • You know you are suppose to have a win because it is a puzzle.
    When you are playing a game of chess you have no one telling you that you have a win in the position! So many of the Lichess puzzles are "Sac the Queen, check, check, check, mate!" It takes experience to look at a position occurring in a real game and see the checks or sacrifices that might be candidates versus the ones that are not. In a real game there may be no immediate win.

  • Are there Lichess puzzles where the solution is to play for a draw?
    In real games you may be fighting to get a draw! If you get the draw instead of losing, then you save half a point.

  • Going for rating puzzle points only can be detrimental to chess improvement.
    Perhaps some people feel that their puzzle rating can be used as a measure of how well they play tactics. Maybe. But it seems to me it measures how well you can solve a puzzle where you know you have a win and hence should be looking at moves that in a real game you would not consider at all; like sacrificing the Queen. If you are not internalizing motifs that occur in the puzzle, then you are not getting the biggest bang for the time you are spending in terms of chess improvement.

A better measure of tactical ability during games would be to go over your own games, find the points where tactics occurred. Say there were n of them. Count how many times you saw the tactic; say that is m. Now you can compute a percentage 100*(m/n). Example, there were 100 tactical opportunities (n=100), you found 80 of those (m=80), so 80% success.

TLDR: For best chess improvement, do deliberate practice on the puzzles and go over them with a strong player. @ThighBald @Puredication Good points in #8 and #6. I do a *lot* of puzzles with my students. There are a number of issues using Lichess puzzles, and I've seen it on other sites as well. You have mentioned some. I'll try to make a list here, but let me say first that there is nothing to compare with having a strong player going over the puzzle with you. Unlike the computer, the strong player can talk to you about the chess ideas that are in the puzzles. He can help you explore why the motifs in the puzzle work, and what would make the motifs not work. In a phrase, "deliberate practice". Of course for many people the points below are irrelevant. They are playing the puzzles for fun. They get it right, they feel good. They get it wrong, well on to the next puzzle. So some problems with puzzles: - Multiple solutions, but only one correct one. I've seen sites where you do not fail the puzzle if you get an alternate solution. I've also see ones where there is a point system for each move and the best move gets the most points etc. What I'm always asking my students is the plan behind their move. The motifs being addressed. For example, in this puzzle above, the motifs are queening a pawn and weaving a mating net. Very few people can see the mate in 11 with 71.Rg5+. That move allows Black to move the King closer to the pawn. Hopefully the student is not playing that move just for the sake of a check! The motif of creating a crises for the Black Knight over the promotion theme is the thing to take away from this puzzle. After 71.Rc5, the Knight cannot get back to stop the pawn and so must exchange itself for the pawn or run away. And then the pawn is going to Queen and mate will follow quickly. There is no need to be calculating either the 9 or 11 move mate. Good players do not calculate that in this position. They'd instantly play 71.Rc5 for the reasons above. They've seen the motifs before. - The puzzle ends without a clear resolution. The student may have no idea how to proceed after getting the puzzle correct. On to the next puzzle, is usually what they do. If they do that, they are missing an opportunity. After having spent time to solve the puzzle, why not spend a little more time and continue with deliberate practice. If you do not know how to win from the position at that point, perhaps you should investigate it. Work it out with computer help, or much better, get a strong player to help. - The puzzles can be solved by guessing with no understanding. This is obviously not the way to get better at chess. - The solution involves moves only a computer would play. As @Puredication pointed out in #6. This happens for both sides. I've seen puzzles where, after the initial "correct" move, the computer plays a move for the opponent that a human would almost certainly not play! Examples abound. Spite checks are my favorite. Second favorite is the computer tossing its Queen away because it sees that it is going to lose it anyway, many moves later! Even if a human saw that, he'd hold the Queen in the hope that his opponent has not seen the win of the Queen! Also, the computer will gladly take a position it has calculated gives it more points, even though it will be hard to defend tactically by a human. Again, a strong player going over the puzzle with you is the best solution to this issue. - You *know* you are suppose to have a win because it is a puzzle. When you are playing a game of chess you have no one telling you that you have a win in the position! So many of the Lichess puzzles are "Sac the Queen, check, check, check, mate!" It takes experience to look at a position occurring in a real game and see the checks or sacrifices that might be candidates versus the ones that are not. In a real game there may be no immediate win. - Are there Lichess puzzles where the solution is to play for a draw? In real games you may be fighting to get a draw! If you get the draw instead of losing, then you save half a point. - Going for rating puzzle points only can be detrimental to chess improvement. Perhaps some people feel that their puzzle rating can be used as a measure of how well they play tactics. Maybe. But it seems to me it measures how well you can solve a puzzle where you know you have a win and hence should be looking at moves that in a real game you would not consider at all; like sacrificing the Queen. If you are not internalizing motifs that occur in the puzzle, then you are not getting the biggest bang for the time you are spending in terms of chess improvement. A better measure of tactical ability during games would be to go over your own games, find the points where tactics occurred. Say there were n of them. Count how many times you saw the tactic; say that is m. Now you can compute a percentage 100*(m/n). Example, there were 100 tactical opportunities (n=100), you found 80 of those (m=80), so 80% success.
#10

@ThighBald The only thing that's clear is that Black doesn't have a prayer. A most puzzling puzzle indeed.

@ThighBald The only thing that's clear is that Black doesn't have a prayer. A most puzzling puzzle indeed.

This topic has been archived and can no longer be replied to.