It’s kind of not exactly chess, but recently I decided to see if 2 kings could trap a knight. Kings not allowed to move into check, of course. I found that they could trap the knight, but wasn’t as easy as I thought.
Then I started wondering if a Rook alone can trap a knight, if two knights can trap a king, or can bishop and knight trap a king; if a rook can't trap a knight, can a rook and knight, etc, etc. There are many more combos that are interesting. Bishops, queens, and rooks can't be trapped, but knights and kings are interesting victims.
I'm wondering if this subject has ever been covered. I just messed with the two kings against knight, and it was pretty interesting geometry of the pieces. The knight can be an elusive critter.
Go to a computer programing website with a forum. One that’s frequented by students learning to program.
Pick any popular lanquage like “C” of any varient, but there are many computer languages to choose from.
Thats just the sort of problem Professors like to hand out as a mental challenge.
It would be a nice side problem to the perennial “Eight Queens” or “Knights Tour” problems that get assigned ad nauseum. I’m sure at least one person would be intriqued by the challenge.
In any event it would be a recursive problem, starting with a mated position and working backwards to see if all moves were forced to achieve the mating positions.
I was under the impression that the stated problems were just pure logical problems and not under any constraints like being a position that could come from a played game.
Of course, that’s true. Many of these positions cannot come from a played game (e.g. because of no king, or multiple kings). They are, as you say, “pure logical problems”.
That’s exactly why it is necessary to have a precise definition of “trap”. A reasonable definition of a “trap” would be a position where, no matter what move the piece makes, it can be captured on the next move.
With this definition, an example of a trap would be a black knight on a8 and a white rook on c6. No matter where the knight moves, the rook can then capture it.
But, if the knight is allowed to stay where it is, then the rook cannot capture it. It would then take a queen, rather than just a rook, to trap the knight.
So, is your definition of “trap” the first (“checkmate” or “stalemate”) version, or the second (“checkmate only”) version? In other words, in the position with black knight on a8 and white rook on c6, is the knight trapped, or not? Inquiring minds need to know.
By definition, a king can’t move into check, so the stipulation is: “Can two kings of the same color corral a knight so that every legal move by the knight results in the knight’s capture?”. No other pieces are allowed on the board.
So you’re going for the “checkmate or stalemate” version then. The knight is trapped if every knight move is to a square where it can be captured, even if it is not en prise on its present square.
The question is, is a piece considered trapped when every square it can move to is en prise, even if the piece is not en prise on its present square (analogous to stalemate), or is the piece considered trapped only when every square it can move to is en prise AND the piece is also en prise on its present square (analogous to checkmate)?
For example, in the following diagram, is the knight trapped, or isn’t it?
I’ve always understood, at least in my mind, that a piece that is NOT under attack, but will be taken the following move, and the opponent is unable to stop it from being taken, would be considered trapped.
But for purity sake, let’s say a piece in immediate "en prise"and trapped at the same time can’t be considered to be trapped unless there was an overriding reason not to take immediately.
I wish the OP would respond to the thread and fill in some holes on his chess problems. We can debate all day the nuances of the problem, but it’s the OP that has the clearest idea of what parameters he wants for each problem.
OK, that much is cleared up then. And I agree that would be the most appropriate (or at least the most fun) definition.
Now you’ve lost me again. It seems to me that, if a piece that can’t safely move but is not currently en prise, is considered trapped, then certainly a piece that can’t safely move and is already en prise would also be considered trapped.
Yes, the OP should weigh in on the same question I asked you. And if his answer is opposite from yours and mine, then you and he (and he and I) are talking over (or would be under?) each other’s heads.
If you allow a piece to become trapped and en prise at the same time, and if your opponent takes that piece and you follow up by crushing the living day lights out him or her, then that’s the scenario in which it would NOT be a good idea to take the “en prise” piece, at least not immediately.
Yes, but as you pointed out earlier, these positions (or puzzles) are “pure logical problems”, where we are not talking about the wisdom or advisability of moves at all.
I don’t think anything I post, or anyone else but the original poster could post would make a difference. Only the OP can clearly define what he means by a trap, and exactly what pieces are allowed on the board, and if they are pure logic problems with or without the opponent’s king.