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Is it possible to fully premove a queen vs lone king endgame?

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RandomChessPlayer0_o

I need to know so that I won't run out of time anymore if I am in such a situation.

llama_l

Off the top of my head... yes, but I'm guessing it might take close to 50 moves.

The process I use for time scrambles is like this

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Obviously these weren't best moves. I was trying to copy how it usually looks during a game.

Keeping the king and queen together does 2 important things:

1) Your queen wont be lost no matter what your premove is
2) Your moves are a short distance, so you can move faster (this is useful in any time scramble).

llama_l

Another tip for time scrambles involving Q vs king (let's pretend they have a few pawns so it's harder)... don't make the mistake of checking over and over... if they premove their king, and you check them, their premove will likely work.

Instead of that, check every 2nd or 3rd move. When it's hard to predict your queen's movement, you'll break their premoves more often, and that way you'll gain time.

llama_l

Ok, last trick I swear tongue.png

You can also do stuff like this

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The point is you stack a few shuffling moves to give yourself a second or two to think. Sometimes I lose track of the position and I need a moment to orient myself, so I'll let my hand make a few non moves while my eyes are trying to assess things... then I start playing again.

llama_l

Oh, if the question is whether it's practically possible, then sure.

If it's theoretically possible (e.g. mate a lone king on an unknown square) probably yes, but it'd be impractical to use in a real game.

SubMinhPiChannelPls
JTZ01
Daddy_Chillimao wrote:

maybe if you are an experienced chess player then yes

if you just started then no

i premoved a pawn to queen the mated ALL IN PREMOVE okay, in just 2 sec FULL PREMOVE its rly hard, i wish i had a faster mouse+not laggy screen

JTZ01
SubMinhPiChannelPls wrote:
 

the thing is u gotta see where the king GOES, which takes abt 1-2 sec

JTZ01

the full premove not knowing where ur opponent moves is rly hard

llama_l
SubMinhPiChannelPls wrote:
 

You lost your queen on move 4.

2...Ke8 3...Kd8 4...Kxd7

You also let the king escape from the corner on move 4.

3...Kh7 4...Kg6

etc

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I'd guess that mating an invisible king that starts on an unknown square is possible in much greater than 50 moves.

And if you know the initial square then around 50 moves... i.e. either way, to mate in a practical game, you have to react to what your opponent is doing.

Arisktotle

Yes, it is possible to play with an invisible king - or even with forces entirely invisible to the adversary - but one needs additional rules about "selfchecking the king". Required is an arbiter (computer is OK) who warns one or both players that a selfcheck has been attempted and demands correction. Can you try any amount of corrections or do you let's say lose after 3 selfchecks in a row?

llama_l
Arisktotle wrote:

Yes, it is possible to play with an invisible king - or even with forces entirely invisible to the adversary - but one needs additional rules about "selfchecking the king". Required is an arbiter (computer is OK) who warns one or both players that a selfcheck has been attempted and demands correction. Can you try any amount of corrections or do you let's say lose after 3 selfchecks in a row?

Oh, I see what you're saying. In practice a player could use illegal moves to discover things about the position.

For a premove algorithm to be correct, I think any illegal move should count as a failure... mostly because I think a premove algorithm like this does exist, so there's no reason to make it easier by saying takebacks are allowed in the case of an illegal move.

llama_l

Off the top of my head, this is the first thing I'd try, just as an example...

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What this does is break the problem into 2 parts: either there is a black king on the h file, or not. First you complete a sequence that mates the black king on the h file, and then you break the board into two parts again, each time making the possible squares smaller in size. Efficiency will be proportional to how many squares you can separate from the problem space, and inversely proportional to how long it takes to mate the king in the smaller space.

The most primitive method would be removing one row or column at a time, but I'm guessing with fancier techniques, you could remove more... in particular against a randomly placed king since you could leave the least likely cases for last, making your algorithm more efficient overall.

llama_l

Maybe a good shorthand for mating an unknown king on the h file... it's (nearly) the same as mating a black king that can pass its turn when not in check.

llama_l

Another way to simulate it, is place 3 or so black kings on the board. After each white move, all Black kings get to either move once or pass their turn...

... looking at this, I don't see a way to clear the 2nd file, so now I'm not sure it's possible to mate an invisible king on an unknown square with just a king and a queen... that's kind of too bad lol. It would have been interesting.

I guess the next question is what's the minimum amount of material you'd need to do it.

RandomChessPlayer0_o

I probably found a method on how to do the queen vs lone king checkmate, all moves being a premove, but it requires lots of thinking and is not useful when in time trouble due to needing to think of all of the possible moves by their opponent's lone king, and the reason it requires thinking even when it's premoves, is because you don't do a premove combo, you just simply premove 1 at a time, so you need to remember which premove you need to play depending on what your opponent plays. I'll keep analyzing to see if my method was right, but for now I can show you a position which you'd like to have when premoving in such an endgame due to it leading to a forced mate with premoves only.

With that position, the king is forced to 1 square everytime, so you don't need to worry about the king escaping while you're premoving.

RandomChessPlayer0_o

Alright, I'm pretty sure I found the method. So your plan will be to box the king somewhere in the area of the red squares:

So what I do to bring the king into the area of the red squares, is to put the king and queen in the center.

This is how I put the king and queen in the center when black's king is boxed in the upper left corner. If the king is in another corner, then I change the position of the king and queen in the center depending on which corner the king is in. For example, if the king is in the bottom right corner, I imagine the upper-left variation when setting up the center position, flipped 180 degrees.

Now, our required position which we will need to achieve is this:

Also, the square colors don't matter or the direction (it can be mirrored, upside-down, etc. depending on where your king is), you only need to get this position, with the king touching the rim by the way. It also doesn't matter if it's black or white to play, because I'll explain how you can checkmate either way, later on in this text. Anyways, to get the king to the red squares and set up the position as shown on the image above, you have to do this:

Opponent's possible moves are marked in blue.

Anyways, now that we reached that position from the image, let's talk about how to turn it into checkmate progress.
If it's White to move:

If it's Black to move:

Anyways, if you want to know how to do the checkmate, then read the message above this current one.

RandomChessPlayer0_o

Funny how I answered my own question on my topic post, lol

magipi

I don't think any of these answers answer the question. None of these is a full premove sequence.

RandomChessPlayer0_o

Yeah I did think of a full premove sequence when making this topic, but later found out that it was impossible, but then I found a way on how to win such an endgame using 1 premove at a time.